Dinosaurs: Why are the herbivours so powerful?

[Rainbownaga]

I have to admit that I'm no expert in dinosaurs, but something seems wrong about the relationship between prey and predators. Namely herbivores seem more powerful than the creatures I would assume would be snacking on them. Triceratops is weaker than T-rex, protoceratops is higher cr than velociraptor and a match for deinonychus.

Firstly, is this right, and secondly, are there any stats for weaker dinosaurs that might have fit in the tyrannosaurs' menu?

[Stormageddon]

I'm no expert either but didn't a lot of preditors hunt in packs?

[Rappy]

Compare a rhinoceros and a lion. Your pop culture classic herbivores like triceratops and stegosaurus are more than capable of defending themselves against the theropods of their respective periods.

If you're looking for a prey item, you have creatures such as camptosaurus (http://www.enworld.org/cc/converted/view_c.php?CreatureID=1266) and struthiomimus (http://www.enworld.org/cc/converted/view_c.php?CreatureID=1167) at your disposal.

[awa]

Keep in mind for many species of large herbivores living and extinct healthy adult male members of the specious often have little to fear from individual preditors its the old, sick, injured or young that are most vulnerable.

[Godskook]

Compare:

Hippo, Elephant, Rhino vs. Cheetah, Lion, Hyena

[Rainbownaga]

Compare a rhinoceros and a lion. Your pop culture classic herbivores like triceratops and stegosaurus are more than capable of defending themselves against the theropods of their respective periods.

If you're looking for a prey item, you have creatures such as camptosaurus (http://www.enworld.org/cc/converted/view_c.php?CreatureID=1266) and struthiomimus (http://www.enworld.org/cc/converted/view_c.php?CreatureID=1167) at your disposal.

Thanks for the links.

And thanks for all the replies. It seems like the actual Tyrannosaur is/was a lot less noble than the one left in my imagination from childhood.

So the assumption is that the T-rex would run in, swallow the baby triceratops and run off before the parents knew what was happening?

[GoodbyeSoberDay]

A lucky T-Rex might do that, yeah. I assume in D&D its diet consists mostly of goblin subsistence farmers.

[pingcode20]

At least, until Advancement: F-14s comes into play.

[Fiendish_Dire_Moose]

Herbivorous are more powerful than carnivores for a reason. I direct you to the documentary of a spinach abusing sailor known as "Popeye". beware kids, spinach abuse is a growing problem in seafaring folk.

[KatfishKaos]

From what I've learnt about the wonderful bipedal monster of doom, it is a scavenger. Think of a seagull on steroids (and its been mutated :P).

[Admiral Squish]

Actually, Big T was a hunter first, but it had no issue with scavenging, either. And let's be honest, would you rather face down a herd of triceratops or a dead stego? Most dangerous thing you'll face with the stego is smaller scavengers, and if they struggle? Heck, even more food!

Generally, velociraptors are thought to hunt in packs like really big, unpleasant wolves. A full pack working together could likely take down even some of the larger prey.

[sonofzeal]

Generally, velociraptors are thought to hunt in packs like really big, unpleasant wolves. A full pack working together could likely take down even some of the larger prey.
Er, common misconception. There's little to no actual evidence to support this beyond the Jurassic Park movies, which didn't even get the name of the species right (what they show is more likely a Deinonychus; actual Veloceraptors are closer in size to a turkey, and feathered). They were predators, though, not scavangers.

[Godskook]

Er, common misconception. There's little to no actual evidence to support this beyond the Jurassic Park movies,

[Assume cocky, know-it-all attitude]

Excuse me! Jurassic Park *IS* actual evidence.

[sonofzeal]

[Assume cocky, know-it-all attitude]

Excuse me! Jurassic Park *IS* actual evidence.
Heh.

Well, it's not unreasonable anyway. It's the sort of thing they might have done, and it'd be hard to tell from the fossil record either way. And there was one dig somewhere that had a bunch of them together, which is what you'd look for if it were the case. Only one though. Science may never know..... :smalleek:

[Satyr]

To be fair, the feathered fossils of the velociraptor were only found or described after the first Jurassic Park movie and probably because of it; I have once read that thanks to the movie, there was an incredible increase in funding for paleontological expeditions, and this is one of the turning points in paleontology all in all, which has boosted the number of findings and descriptions more than any other event since the 19th century.

Some of the larger therapods were supposedly pack hunters, according to foot prints which were found and which suggests that a small group were travelling together. And I think there was even a fossil found that suggested similar activities, at least for some predators.

[Admiral Squish]

Er, common misconception. There's little to no actual evidence to support this beyond the Jurassic Park movies, which didn't even get the name of the species right (what they show is more likely a Deinonychus; actual Veloceraptors are closer in size to a turkey, and feathered). They were predators, though, not scavangers.

...Wow. I just wikied that to check, and yah. Well, there goes MY childhood.

Still, the evidence of Deinonychus Vs. Tenontosaurus indicates pack behavior. A two-ton beast is not going to get taken out easily by a meter-tall predator working solo.

[Rainbownaga]

At least, until Advancement: F-14s comes into play.

I love that image, do you remember where it was from? Unfortunately my pc's are still only level 2 so it'll be a while before they face a t-rex let alone one in a jet fighter.



Some of the larger therapods were supposedly pack hunters, according to foot prints which were found and which suggests that a small group were travelling together. And I think there was even a fossil found that suggested similar activities, at least for some predators.

That makes the stats make a lot more sense.

[TheCountAlucard]

I love that image, do you remember where it was from?Calvin and Hobbes, of course. :smallsmile:

[Admiral Squish]

I love that image, do you remember where it was from? Unfortunately my pc's are still only level 2 so it'll be a while before they face a t-rex let alone one in a jet fighter.

HOLY CRAP I totally didn't get the reference until you mentioned them being in jet fighters.

Don't we all love little Calvin's imagination?

Edit: Ninja'd. So close...

[Serpentine]

If I recall correctly (which I may not) at the time of writing Jurassic Park, velociraptors were considered to be the same as Deinonychus, or something like that. The gist of this vague memory, anyway, is that when it was written, the velociraptor part of Jurassic Park at least adhered to part of current scientific thought, which was only later proven to be incorrect.

But yeah, even getting away from the super-herbivores, compare deer/bison vs. wolves. There're a few ways for prey to go: camouflage (e.g. moths), mimicry (e.g. bird poo caterpillar), unpalatability (e.g. poison arrow frogs), hiding and dodging (e.g. mice, other small mammals), speed (e.g. antelope) or intimidation/brute strength/other defenses (e.g. bison, elephants, moose, etc). From the looks of things, many herbivorous dinosaurs, specifically those statted out in D&D, went the latter route, developing in such a way that we would in fact expect any one herbivore to be tougher and more than a match for any one predator.

[hamishspence]

They were considered to be the same genus by one scientist- whose ideas ended up being demonstrated to be in error on this point.

Apart from him- I don't think many people thought they were the same genus.

The Jurassic Park ones are slightly heftier even than Deinonychus was.

[sonofzeal]

If I recall correctly (which I may not) at the time of writing Jurassic Park, velociraptors were considered to be the same as Deinonychus, or something like that. The gist of this vague memory, anyway, is that when it was written, the velociraptor part of Jurassic Park at least adhered to part of current scientific thought, which was only later proven to be incorrect.
It's.... complicated. The books could make a pretense of accuracy as at least some referred to Deinonychi as "velociraptor antirrhopus" (it's now "Deinonychus antirrhopus"), but it did actually use the phrase "velociraptor mongoliensis" which refers specifically to the turkey-sized ones, so there goes that. Close, at least.

The movie's flat-out wrong though, on several fronts, and almost certainly knew it but went through anyway for the sake of drama and excitement.

[starwoof]

Actually the Jurassic Park raptors are probably Utahraptors, not Deinonychus.

[Ravens_cry]

Among the most dangerous large animals are the big herbivorous mammals, the last of the megafauna. Cape Buffalo and Hippopotamus are pretty near the top cause of deaths by large animals in Africa. Even more then crocodiles I have heard.
Now, we don't know if Triceratops, Stegosaurus and Apatosaurus were like this, because, alas, there is none extant. But it seems to me to be a reasonable extrapolation.

[Satyr]

No, they are way to small for Utahraptors, if you consider them to be grown up individuals.

[sonofzeal]

Actually the Jurassic Park raptors are probably Utahraptors, not Deinonychus.
Except Utahraptors are seven meters long, making them considerably bigger than the movie ones, and weren't even discovered when shooting began. The production crew out-and-out said that they based them on Deinonychus (though they're slightly too big, the tail's too short and flexible, and there's a couple other issues known at the time even without the feathery stuff we've found since).

[Ravens_cry]

The reason they are called velociraptor in Jurassic Park is simple. It's just that more badass a name.

[Rappy]

They were considered to be the same genus by one scientist- whose ideas ended up being demonstrated to be in error on this point.

Apart from him- I don't think many people thought they were the same genus.
This (http://blogs.smithsonianmag.com/dinosaur/2008/11/07/you-say-%E2%80%9Cvelociraptor%E2%80%9D-i-say-%E2%80%9Cdeinonychus%E2%80%9D/) sums it up rather well.

Also, on theropod pack hunting: there is at least evidence for tyrannosaurid pack hunters.

Also also, on Tyrannosaurus rex being a giant vulture: No vertebrates (no, not even that one) are truly full scavengers, last time I checked. Big T certainly wouldn't pass up an easy meal of Sun-baked Hadrosaurine Carcass, but it wouldn't actively avoid hunting for prey either. The bigger myth is that tyrannosaurus and triceratops actively engaged in epic duels to the death. While there are some trike fossils that have evidence of tyrannosaurid bite marks, these are more likely an exception rather than a rule.

[hamishspence]

Partially healed bit marks matching Tyrannosaurus teeth, do suggest it attacked live prey- and sometimes, the prey got away.

As to how fast it was- given the long legs (proportionally longer than other big theropods) reinforced ankles, and so on, it may not have been as fast as some people theorize, but it was fast enough.

[Rainbownaga]

The bigger myth is that tyrannosaurus and triceratops actively engaged in epic duels to the death.

:smallfrown:

Epic duels are epic

:smallfrown:

[Volkov]

Tyrannosaurus rex is hideously underpowered. He'd be able to kill spinosaurus with one bite to the neck (I.E one critical hit) or simply overpower it. Seismosaurus gets a chomp to it's nice long, skinny neck which is in Rexy's reach. Anky can be flipped over, and Triceratops is the only one who actually presents a decent threat, and it's evident that the triceratops loses out most of the time.

[AslanCross]

Calvin and Hobbes, of course. :smallsmile:

http://iconicionic.files.wordpress.com/2008/01/tyrannosaurus_in_f-14s.jpg

Best encounter ever. Ah, Calvin and Hobbes, my childhood obsession.

[Volkov]

http://iconicionic.files.wordpress.com/2008/01/tyrannosaurus_in_f-14s.jpg

Best encounter ever. Ah, Calvin and Hobbes, my childhood obsession.

Needz Moar Dakka! :smallsmile:

[PhoenixRivers]

Tyrannosaurus rex is hideously underpowered. He'd be able to kill spinosaurus with one bite to the neck (I.E one critical hit) or simply overpower it. Seismosaurus gets a chomp to it's nice long, skinny neck which is in Rexy's reach. Anky can be flipped over, and Triceratops is the only one who actually presents a decent threat, and it's evident that the triceratops loses out most of the time.

I don't think you grasp Seismosaurus's sheer bulk. It's theorized that the animal faced away from significant predators, and used its tail as a 3 ton club. One hit from that thing, with the estimated mass, and any bipedal dinosaur would be crippled for life, if it was lucky.

Anklyosaurus had a very low center of gravity. It would be difficult for a creature with appendages and thumbs to flip it, much less something with shriveled chicken wing arms. Add in the fact that its tail could easily break legs (a life-ending injury, in those times), and it was by no means a sure thing.

[Volkov]

I don't think you grasp Seismosaurus's sheer bulk. It's theorized that the animal faced away from significant predators, and used its tail as a 3 ton club. One hit from that thing, with the estimated mass, and any bipedal dinosaur would be crippled for life, if it was lucky.

Anklyosaurus had a very low center of gravity. It would be difficult for a creature with appendages and thumbs to flip it, much less something with shriveled chicken wing arms. Add in the fact that its tail could easily break legs (a life-ending injury, in those times), and it was by no means a sure thing.

At only 35 tons it's a sauropod light weight. Also, it survived only because most carnivores at the time couldn't reach it's neck nor clamp down hard enough to crush it's windpipe.

Tyrannosaurus could use it's massive head for leverage, just because we use arms to flip things over doesn't mean everything else has to.

[PhoenixRivers]

At only 35 tons it's a sauropod light weight. Also, it survived only because most carnivores at the time couldn't reach it's neck nor clamp down hard enough to crush it's windpipe.

Tyrannosaurus could use it's massive head for leverage, just because we use arms to flip things over doesn't mean everything else has to.

Or the fact that top heavy bipeds had a difficult time running and circling it faster than a three ton tail could move. It's easier and faster to turn in a circle than it is to run around something. T-rex may have a shot if he caught such a creature by surprise, but when aware? Slim odds. Especially if the animal moved in herds. To Illustrate the danger of a 3 ton tail on a 25 ton predator? Assume you weigh 180 pounds. Swing a 22 pound bludgeon into your chest as high speed, and see what it does to your ribcage.

As for using a head for leverage? Let's also remember they had brains the size of walnuts, rendering such a complex maneuver all but impossible. in addition, low center of gravity means that hitting it from the side moves it sideways. It's like seeing a penny on the sidewalk, and trying to flip it by punching it repeatedly. To effectively flip such a thing, you have to get under it... Something a Massive object would have trouble doing. Again, not as sure as you'd like to think.

Was the T-rex dangerous? Yes. Was it a killing machine, easily capable of trouncing every dinosaur out there? Only in the minds of fans more concerned with "cool" than "likely".

[Volkov]

Or the fact that top heavy bipeds had a difficult time running and circling it faster than a three ton tail could move. It's easier and faster to turn in a circle than it is to run around something. T-rex may have a shot if he caught such a creature by surprise, but when aware? Slim odds. Especially if the animal moved in herds.

As for using a head for leverage? Let's also remember they had brains the size of walnuts, rendering such a complex maneuver all but impossible. in addition, low center of gravity means that hitting it from the side moves it sideways. It's like seeing a penny on the sidewalk, and trying to flip it by punching it repeatedly. To effectively flip such a thing, you have to get under it... Something a Massive object would have trouble doing. Again, not as sure as you'd like to think.

Was the T-rex dangerous? Yes. Was it a killing machine, easily capable of trouncing every dinosaur out there? Only in the minds of fans more concerned with "cool" than "likely".
Stegosaurus had a brain the size of a walnut, T-Rex was as smart as a Cuban crocodile, which are very intelligent and resourceful animals. The only dinosaurs that would trounce a lone Tyrannosaurus Rex every time are the very largest of the Sauropods, Inlcuding such 100+ ton giants such as Argentinosaurus, or Amphicoelias.

[PhoenixRivers]

Stegosaurus had a brain the size of a walnut, T-Rex was as smart as a Cuban crocodile, which are very intelligent and resourceful animals.

Provide evidence to the observed intellectual processing capability of an animal that disappeared off the planet thousands of years before the first observers began observing. Please.

In addition, continue trying to flip a penny by punching it, or to flip a pancake with a playstation 3. That's the level of finesse you have, and the complexity of the task.


The only dinosaurs that would trounce a lone Tyrannosaurus Rex every time are the very largest of the Sauropods, Inlcuding such 100+ ton giants such as Argentinosaurus, or Amphicoelias.You don't need to kill the animal to kill the animal. A broken bone is life threatening in those times, especially if it's in the chest or leg... which is most of the T-rex.

You're acting as if a tiger has a 100% chance of taking down a rhino, or a wolf could easily drop a full grown bison. It's not as open/shut as you think.

[Volkov]

Provide evidence to the observed intellectual processing capability of an animal that disappeared off the planet thousands of years before the first observers began observing. Please.

In addition, continue trying to flip a penny by punching it, or to flip a pancake with a playstation 3. That's the level of finesse you have, and the complexity of the task.

Ahem, you were saying? (http://dinosaurs.about.com/od/dinosaurbasics/a/dinosmarts.htm)

[PhoenixRivers]

Ahem, you were saying? (http://dinosaurs.about.com/od/dinosaurbasics/a/dinosmarts.htm)

The entire process relies on measuring the size of a brain, and using it to compute its prowess.

By that logic, a dump truck should beat a Ferrari in a race every time.

Scientists have a large amount of difficulty measuring human intelligence, and we have those right here, right now. Any standard we have for measurement is horribly inaccurate and flawed.

What we DO know is that these animals all thrived. If the T-rex was become death, destroyer of all dinosaurs whose folly it was to meet it, then the other animals would have died out from hunting. This did not happen, so we can assume that the T-rex isn't the E-bola of the apex predator community. Thanks for playing though.

[Volkov]

The entire process relies on measuring the size of a brain, and using it to compute its prowess.

By that logic, a dump truck should beat a Ferrari in a race every time.

Scientists have a large amount of difficulty measuring human intelligence, and we have those right here, right now. Any standard we have for measurement is horribly inaccurate and flawed.

What we DO know is that these animals all thrived. If the T-rex was become death, destroyer of all dinosaurs whose folly it was to meet it, then the other animals would have died out from hunting. This did not happen, so we can assume that the T-rex isn't the E-bola of the apex predator community. Thanks for playing though.

It's better than nothing, thus we use it. It is also a logical fallacy to say we should get rid of something because it is not %100 effective.

Also, Tyrannosaurus rex forced all other large carnivores in it's area into extinction, when Daspletosaurus became Tyrannosaurus, the Albertosaurines disappeared completely, showing that Tyrannosaurus was such an efficient hunter that no other large carnivores could coexist with it.

[PhoenixRivers]

It's better than nothing, thus we use it.

Also, Tyrannosaurus rex forced all other large carnivores in it's area into extinction, when Daspletosaurus became Tyrannosaurus, the Albertosaurines disappeared completely, showing that Tyrannosaurus was such an efficient hunter that no other large carnivores could coexist with it.

from your article:
Advanced-Placement Carnivores

One of the tricky aspects of animal intelligence is that, as a rule, a creature only has to be just smart enough to prosper in its immediate environment. Since the plant-eating sauropods were so massively dumb, the predators that fed on them only needed to marginally smarter--and most of the relative increase in the brain size of these carnivores can be attributed to their need for better vision and muscular coordination. (For that matter, the reason the sauropods were so dumb is that they only had to be marginally smarter than plants!)

However, it's possible to swing too far the other way and exaggerate the intelligence of dino carnivores. For example, the doorknob-turning, pack-hunting Velociraptors of Jurassic Park are a complete fantasy--if you met a live Velociraptor today, it would probably strike you as slightly dumber than a modern bird of the same size. You certainly wouldn't be able to teach it tricks, since its EQ wouldn't be in the same ballpark as a dog or cat.

Better than nothing, so we use it? Guess what? That doesn't mean it's accurate, or correct. All it means is that it's less prone to inaccuracy than, say, using wild speculation to feed a fantasy notion about the superintelligence of a T-rex.

Edit: And more! Links from your article!
T. Rex appears to have had a fairly large brain by Cretaceous standards (although today it would be outwitted by a newborn kitten).

[hamishspence]

Not just measuring the size of the brain, but measuring the size of the component parts.

Some parts of the brain are more important to "thinking" than others.

[PhoenixRivers]

Not just measuring the size of the brain, but measuring the size of the component parts.

Some parts of the brain are more important to "thinking" than others.

And, as is evidenced by the article, all were lacking in the "supergenius" that was the T-rex.

[Volkov]

from your article:

Better than nothing, so we use it? Guess what? That doesn't mean it's accurate, or correct. All it means is that it's less prone to inaccuracy than, say, using wild speculation to feed a fantasy notion about the superintelligence of a T-rex.

Edit: And more! Links from your article!

And guess what, a Cuban crocodile's intelligence level is at that level.

[PhoenixRivers]

And guess what, a Cuban crocodile's intelligence level is at that level.

And guess what? The Cuban Crocodile has, from a wiki research, shown the ability to:
Jump after prey that's high up.
pack hunt (isolated occurrance).

That's about it, unless you'd care to cite a source, showing this as an animal both too dumb to outwit a kitten, and yet smart enough to understand about flipping animals. Such tactics are common in hunting cats that go after turtles... Adult, experienced hunting cats, which are much more able to outwit things than a kitten....

But not so much others.

EDIT: Further research: Cuban Crocs don't flip turtles, they crush their shells! (http://www.angelfire.com/mo2/animals1/crocodile/cubcroc.html) So much for that myth.

EDIT2: Your own article states that the smartest of the smart dinos was on par with the dumbest of the dumb animals today. What does that mean? It means that intelligence is not the thing you should be arguing here.

[hamishspence]

While T.rex would never have met "Seismosaurus" (aka Diplodocus hallorum), it is true that there was a sauropod of comparable weight but shorter length around at the time.

Alamosaurus.

Is there anything suggesting that Alamosaurus was being preyed on by tyrannosaurs? Bite marks? Partially healed bite marks?

[Knaight]

Its certainly not unreasonable prey, if caught by surprise, but there were smaller things to go after at the time. Maybe not the various bug eaters out there, but the occasional medium sized carnivore or herbivore is far preferable than any of the very large herbivores, particularly the ankylosaurous genus.

[Rappy]

While T.rex would never have met "Seismosaurus" (aka Diplodocus hallorum), it is true that there was a sauropod of comparable weight but shorter length around at the time.

Alamosaurus.

Is there anything suggesting that Alamosaurus was being preyed on by tyrannosaurs? Bite marks? Partially healed bite marks?
Other than finds off both species together in the North Horn formation? No, not really. It's likely that Alamosaurus sanjuanensis was most likely not on the Tyrannosaurus rex menu due to virtue of its sheer bulk. Why go after the heavyweight contender in the region when there are hadrosaurs nearby?

EDIT: Beaten to the punch by Knaight.

[Oslecamo]

Recent studies even point that the T-Rex was just an overglorified oportunist, using his massive jaw to crush and eat dead bodies it found as fast as possible, and only attacking weakened animals when there were no corpses present.

Actualy, most predators in history go for the wounded/sick large herbivores. Large healthy herbivore are normaly more than strong enough to fend off lone predators. That's how they can afford to be large herbivores!

Honestly, if your large size doesn't allow you to defend yourself from large predators, then you're just a bigger juicier target for said predators, and that's awfull from an evolution standpoint.

That's why most huge mammals from the Ice Age went extinct. They were just bigger targets for our spears and bows!

[PhoenixRivers]

Was about to comment on the North Horn formation. They've found t-rex teeth there, and alamosaurus skeletons there, but didn't find evidence of one used on the other.


Recent studies even point that the T-Rex was just an overglorified oportunist, using his massive jaw to eat and crush dead bodies it found as fast as possible, and only attacking weakened animals.

Actualy, most predators in history go for the wounded/sick large herbivores. Large healthy herbivore are normaly more than strong enough to fend off lone predators. That's how they can afford to be large herbivores!

Honestly, if your large size doesn't allow you to defend yourself from large predators, then you're just a bigger juicier target for said predators, and that's awfull from an evolution standpoint.

+1.

Even modern day apex predators balk at hunting large herbivores, instead picking off the weak, elderly, and young.

The risk is simply too great. Lions have to be on the brink of starvation before they actively go toe to toe with full grown, healthy bison. This is because one good hit, and there's one less predator.

[Oslecamo]

The risk is simply too great. Lions have to be on the brink of starvation before they actively go toe to toe with full grown, healthy bison. This is because one good hit, and there's one less predator.

Heck, just one broken bone will be more than enough to screw over the predator, as he'll be unable to catch more prey. He'll never heal fast enough before starving to death.

[PhoenixRivers]

Heck, just one broken bone will be more than enough to screw over the predator, as he'll be unable to catch more prey. He'll never heal fast enough before starving to death.

Assuming disease from a wound doesn't do it in, of course.

[Zom B]

But yeah, even getting away from the super-herbivores, compare deer/bison vs. wolves. There're a few ways for prey to go: camouflage (e.g. moths), mimicry (e.g. bird poo caterpillar), unpalatability (e.g. poison arrow frogs), hiding and dodging (e.g. mice, other small mammals), speed (e.g. antelope) or intimidation/brute strength/other defenses (e.g. bison, elephants, moose, etc).

There's one you kind of forgot, and it's not so much a defense mechanism as a meta-defense: fast breeding. You see, if the population can multiply as fast or faster than predators can eat them, the net effect is the same as if the victims had escaped the predators, but with the benefit that the predators actually get fed and probably don't come back immediately to kill more, like they would if their first target had gotten away.

[PhoenixRivers]

There's one you kind of forgot, and it's not so much a defense mechanism as a meta-defense: fast breeding. You see, if the population can multiply as fast or faster than predators can eat them, the net effect is the same as if the victims had escaped the predators, but with the benefit that the predators actually get fed and probably don't come back immediately to kill more, like they would if their first target had gotten away.

Or another factor: Appetite of an animal. Most of a 35 ton dino would rot before being eaten. Smaller dino's feed it just as well, at less risk.

Titanosaurs were likely not rapid breeders. Smaller animals? Much more likely.

Remember folks: Trex didn't have something to prove. It just had a stomach to fill. The most effective way to do that safely was to bully smaller animals, and kill the sick and wounded.

[Dyllan]

:smallfrown:

Epic duels are epic

:smallfrown:

In this case, it's unlikely they are.

In order to get an Epic Triceratops, assuming Epic requires a CR over 20, we have to advance it at a minimum to 46 hit dice (that's +30 animal HD, for a +10 CR increase, and two size categories for another +2 CR, going by the MM guidelines). That's a mere 2 HD shy of the maximum for that creature.

The Tyrannosaurus, being 1 CR less to start, would require an additional 33 HD, and two size categories, putting it at 51 HD - just three short of max. And that would make them both CR 21, by the book (although any party with fly and a bow could take them down... but we're talking about Dino v. Dino action here). The odds of two such advanced gargantuan specimens facing off in the wild is incredibly remote. Although, I suppose, theoretically possible within the confines of RAW.

But in most cases, such epic battles would be incredibly sub-epic.

[Oslecamo]

Assuming disease from a wound doesn't do it in, of course.

That's probably the least of their worries. Most predators have a superior natural resistance to diseases, since a good part of their diet will be sick animals and half-rotten flesh, both crawling with all kind of nasty things that can easily enter their bloodstream trough cuts in the mouth.

Herbivores with their "healthier" lifestyle rarely develop such resistances.

Heck, the Komodo dragon has such filthy life habits that some teeth scratches from it is enough to fall large herbivores, because of all the bacterias and diseases in his saliva. He gives a small bite, then waits for the prey to fall down of agony.


Zom B:You forget that breeding also applies to predators. The more food available, the more cubs grow to become full predators.

The less prey available, the less cubs make it to adulthood due to the lack of food, resulting in less predators.

[Ravens_cry]

That's probably the least of their worries. Most predators have a superior natural resistance to diseases, since a good part of their diet will be sick animals and half-rotten flesh, both crawling with all kind of nasty things that can easily enter their bloodstream trough cuts in the mouth.

Herbivores with their "healthier" lifestyle rarely develop such resistances.

Heck, the Komodo dragon has such filthy life habits that some teeth scratches from it is enough to fall large herbivores, because of all the bacterias and diseases in his saliva. He gives a small bite, then waits for the prety to fall dead.

Not quite, though that's a commonly believed myth. Komodo dragons actually have a venom that decreases blood pressure, making the victim go into shock (http://news.nationalgeographic.com/news/2009/05/090518-komodo-dragon-venom.html).

[PhoenixRivers]

Not quite, though that's a commonly believed myth. Komodo dragons actually have a venom that decreases blood pressure, making the victim go into shock (http://news.nationalgeographic.com/news/2009/05/090518-komodo-dragon-venom.html).

Actually, both are true (http://en.wikipedia.org/wiki/Komodo_dragon).

While yes, it is a venom, the creature (in the wild) has a copious amount of bacteria.


Auffenberg described the Komodo dragon as having septic pathogens in its saliva, specifically the bacteria: Escherichia coli, Staphylococcus sp., Providencia sp., Proteus morgani and P. mirabilis.[25] He noted that while these pathogens can be found in the mouths of wild Komodo dragons, they disappear from the mouths of captive animals, due to a cleaner diet.[25][26] This was verified by taking mucous samples from the external gum surface of the upper jaw of two freshly captured individuals.[25][26] Saliva samples were analyzed by researchers at the University of Texas who found 57 different strains of bacteria growing in the mouths of three wild Komodo dragons including Pasteurella multocida.[9][27] The rapid growth of these bacteria was noted by Fredeking: "Normally it takes about three days for a sample of P. multocida to cover a petri dish; ours took eight hours. We were very taken aback by how virulent these strains were".[28] This study supported the observation that wounds inflicted by the Komodo dragon are often associated with sepsis and subsequent infections in prey animals.[27]

In late 2005, researchers at the University of Melbourne speculated that the perentie (Varanus giganteus), other species of monitor, and agamids may be somewhat venomous. The team believes that the immediate effects of bites from these lizards were caused by mild envenomation. Bites on human digits by a lace monitor (V. varius), a Komodo dragon, and a spotted tree monitor (V. scalaris) all produced similar effects: rapid swelling, localized disruption of blood clotting, and shooting pain up to the elbow, with some symptoms lasting for several hours.[29]

In 2009, the same researchers published further evidence demonstrating that Komodo dragons possess a venomous bite. MRI scans of a preserved skull showed the presence of two venom glands in the lower jaw. They extracted one of these glands from the head of a terminally ill specimen in the Singapore Zoological Gardens, and found that it secreted a venom containing several different toxic proteins. The known functions of these proteins include inhibition of blood clotting, lowering of blood pressure, muscle paralysis, and the induction of hypothermia, leading to shock and loss of consciousness in envenomated prey.[30][31] As a result of the discovery, the previous theory that bacteria were responsible for the deaths of komodo victims was disputed.[32]

[Serpentine]

Triceratops is the only one who actually presents a decent threat, and it's evident that the triceratops loses out most of the time.Evident where, exactly? If the triceratops "lost out most of the time", they would not have been a viable species. Almost no predator, alive or dead, would ever go after a healthy adult prey. It's as simple as that. Bulk, horns, a big-arse tail, fins over their spines, they're all adaptations to make sure that they don't get et. More than that, they're adaptations to make sure that the predator doesn't even try to eat them - look at the leaps of the springboks, which only exist to show the lion "how alert and fast and strong I am! You shouldn't even bother trying to come after me!" Because being chased takes it out of the prey, as well, even if it doesn't get caught. The energy used to run away could mean one less young successfully produced that season, or one less week before succumbing to a drought.
But predators live on a knife edge, even more than prey. One injury, even a small one, and that's it for them. That's already been mentioned. But more than that: one failed attempt to catch prey, and it may not have the energy to try again, and that's it for them. And an adult, healthy triceratops or any of the others, would be far, far too risky for anything other than the most desperate of t-rexes (or any of the other, far cooler, large bipedal predators of that era). It's about risk, not just ability. Healthy adults are far riskier than young, old or sick individuals, and so that is what the vast majority of (large) predators go after. I am not aware of any reason to think dinosaurs were any different in this regard.
Now, in terms of D&D Challenge Rating? It is possible that t-rexes are underpowered. After all, a random encounter isn't designed or run with ecology or the desire of the creature to live another day in mind. With that in mind, for all a t-rex wouldn't go up against a healthy adult triceratops, in D&D terms perhaps it could. But your reasoning in the post quoted above is sorely lacking for this possibly sound conclusion.


There's one you kind of forgot, and it's not so much a defense mechanism as a meta-defense: fast breeding. You see, if the population can multiply as fast or faster than predators can eat them, the net effect is the same as if the victims had escaped the predators, but with the benefit that the predators actually get fed and probably don't come back immediately to kill more, like they would if their first target had gotten away.That's not an individual means of defense. All the ones I listed were means by which the chances for survival of single animals are increased. That is, the fact that its siblings will have lots of offspring doesn't help the antichinus that's about to get nommed by a quoll. The fact that it's small, fast and has dirt-coloured fur, however, does. So no, I didn't forget it, it didn't fit in my list :smalltongue:
Not quite, though that's a commonly believed myth. Komodo dragons actually have a venom that decreases blood pressure, making the victim go into shock (http://news.nationalgeographic.com/news/2009/05/090518-komodo-dragon-venom.html).Not so much a myth as something we only just found out.

[Ormagoden]

I shall direct all of you to this link (http://www.youtube.com/watch?v=LU8DDYz68kM).
<WARNING: If you are of light heart and don't think you can handle animals hunting in a natural setting. Don't click on the link.>

Generally herbivores are active in large groups.
This makes picking off an individual much harder, this includes the sick, old, or injured.

[PhoenixRivers]

Not so much a myth as something we only just found out.

As pointed out earlier, both were true. The komodo does have a venomous bite, as well as a host of highly aggressive strains of disease.

While the toxin is generally responsible for the bulk of the kills, the disease is present, and is highly aggressive, compared to other strains of the same disease.

[Evard]

Actually they have found that the T-rex was most likely a scavenger, his head and body composition would be to weird for fighting. Many of the herbivores were not like cows of today (easily taken down) but had body armor or spikes to defend themselves.

The real predators were things like raptors :D who hunted in packs like wolves and even a single one was deadly :p

[Serpentine]

Hell, most of the herbivores of today aren't like cows (and sheep, and anything else bred into generally docile lumps of fleshy by humanity).

PR: My point of contention with that statement remains valid :smalltongue:

[hamishspence]

Questions might include:

Why would T.rex get that big in the first place? Size comes at a lot of costs- if there wasn't a selective advantage to being big, it wouldn't have gotten big.

Why does it retain all the speed adaptations of its ancestors?

Why was there an evolutionary trend toward binocular vision in tyrannosaurs?

(earlier species had eye sockets which did not point forward as much- there is a clear trend toward increasingly advanced binocular vision)

Did large theropods hunt in groups?

[Volkov]

Actually they have found that the T-rex was most likely a scavenger, his head and body composition would be to weird for fighting. Many of the herbivores were not like cows of today (easily taken down) but had body armor or spikes to defend themselves.

The real predators were things like raptors :D who hunted in packs like wolves and even a single one was deadly :p

that theory is discredited, there were no raptors present in tvrexes time that were bigger than a medium sized dog. thus, t-rex couldnmt have fed itself if it were a scavenger. Also, explain why albertasaurus and its ilk went extinct not long after T.rex popped up.

[hamishspence]

Austroraptor was the closest thing to a large dromaeosaur in that approximate time period- found around 70 million years ago- however, it had tiny arms, and hasn't yet been discovered in North America.

Achillobator and Utahraptor- the biggest of the long-armed dromaeosaurs- had been extinct for some time by then.

I suppose the neovenatorids (large allosaurs with long arms) may possibly qualify as competition- Orkoraptor was around in North America quite late.

EDIT: Apparently Orkoraptor is South American.

So- no major competition for T. rex.

[Satyr]

The T-Rex was pobably one of the most defining landliving predators of its time. That doesn't mean that it was an unstoppable killing machine, though. Interestingly, it is not impossible that some animals of one genus hunted specific prey which was not part of the usual diet for other animals of the same species; there is one documented case of a lion pack that sometimes hunts elephants, but this is highly unusual for lions (or large cats in general; tigers don't hunt elephants either).

In addition, there are different hunting strategies; the bulky tyrannosaurs like T.Rex seem to be build more for brute strength than for speed and agility (compared to, let's say an Albertosaur) and it is thus likely that they attacked comparatively slow prey (which on the other hand could have been relied more on size for protection than on speed).

And the bulky tyrannosauroids like T Rex and the leaner, probably quicker tyrannosauroids like Albertosaur existed paralelly and went extinct about the same time, at least due to my sources.

[Volkov]

The T-Rex was pobably one of the most defining landliving predators of its time. That doesn't mean that it was an unstoppable killing machine, though. Interestingly, it is not impossible that some animals of one genus hunted specific prey which was not part of the usual diet for other animals of the same species; there is one documented case of a lion pack that sometimes hunts elephants, but this is highly unusual for lions (or large cats in general; tigers don't hunt elephants either).

In addition, there are different hunting strategies; the bulky tyrannosaurs like T.Rex seem to be build more for brute strength than for speed and agility (compared to, let's say an Albertosaur) and it is thus likely that they attacked comparatively slow prey (which on the other hand could have been relied more on size for protection than on speed).

And the bulky tyrannosauroids like T Rex and the leaner, probably quicker tyrannosauroids like Albertosaur existed paralelly and went extinct about the same time, at least due to my sources.
Daspletosaurus became Tyrannosaurus, Gorgosaurus, who coexisted with Daspletosarus, left no descendants. There was dryptosarus and appilachiosaurus, but he was on the other side of the western interior sea.

[PhoenixRivers]

Questions might include:

Why would T.rex get that big in the first place? Size comes at a lot of costs- if there wasn't a selective advantage to being big, it wouldn't have gotten big.To increase the size of prey it could safely take down. Larger animals can safely take down bigger creatures than smaller ones. This doesn't mean a 30 ton T Rex has any expectation of safely engaging a 35 ton dino.


Why does it retain all the speed adaptations of its ancestors?Because there's no reason to lose it.


Why was there an evolutionary trend toward binocular vision in tyrannosaurs?

(earlier species had eye sockets which did not point forward as much- there is a clear trend toward increasingly advanced binocular vision)Well, binocular vision gives depth perception. This type of processing takes a large amount of brain power to process, however, and is indicative of the uses of the T Rex brain (for information processing and muscle coordination).

[Dire Moose]

As a side note, the fact that velociraptors are small, feathery creatures would lend itself to creative use of the Fling Ally feat for a druid with a velociraptor companion and the ability to summon more velociraptors.

[Volkov]

Also, I should point out that both Drypto and Appilachio were tyrannosaurs. Asia and North America was truely the turf of the Tyrannosaurs, no other type of carnivore grew to large sizes there by the late cretaceous. Gigantoraptor (a three ton oviraptor) and Deinocheirus (a 9 ton ornithomimid) were most likely omnivores and thus don't count.

[Kaiyanwang]

Modern Hyenas are both hunters and scavengers (primarly one or another, depending from the specie).

So, couldn't it be the same for carnivore dinosaurs?

[PhoenixRivers]

Modern Hyenas are both hunters and scavengers (primarly one or another, depending from the specie).

So, couldn't it be the same for carnivore dinosaurs?

Yes. However, the universal of predators in the wild:

If they're engaging a larger animal, they're either starving, or they're in a pack.

[Oslecamo]

Why would T.rex get that big in the first place? Size comes at a lot of costs- if there wasn't a selective advantage to being big, it wouldn't have gotten big.

The bigger you are, the more effecient are your energy processation capacities and conservation. You can also carry more fat.

Thus, for a scanvenger is great to be big, since he can afford to wait longer untill he finds a new corpse and then afford to eat a big chunk of said corpse.

Big fast legs and good vision are also both important to finding corpses.

[Project_Mayhem]

In this thread: Dino rage :smallbiggrin:

[Drakyn]

Modern Hyenas are both hunters and scavengers (primarly one or another, depending from the specie).

So, couldn't it be the same for carnivore dinosaurs?

Because it's much more satisfying to claim that a Tyrannosaurus
(A) COULD EAT ANYTHING MUAHAHAHAHAHAHAHAH

or
(B) Actually was a big fat corpse-eating wussy that all those little fanboys out there can't handle the truth of http://i.somethingawful.com/forumsystem/emoticons/emot-smug.gif

Pretty much no predator turns up its nose at carrion, and pretty much no predator does nothing but scavenge. The "we-found-partially-healed-t-rex-bite-marks-in-bones" has already been cited. Given anything we know about carnivore behaviour, it's pretty easy to say that T. rex was typical, and not some anomalous 110% scavenger evolved solely to make 5-year-olds suffer crushed dreams and cry themselves to sleep.

[chiasaur11]

Because it's much more satisfying to claim that a Tyrannosaurus
(A) COULD EAT ANYTHING MUAHAHAHAHAHAHAHAH

or
(B) Actually was a big fat corpse-eating wussy that all those little fanboys out there can't handle the truth of http://i.somethingawful.com/forumsystem/emoticons/emot-smug.gif

Pretty much no predator turns up its nose at carrion, and pretty much no predator does nothing but scavenge. The "we-found-partially-healed-t-rex-bite-marks-in-bones" has already been cited. Given anything we know about carnivore behaviour, it's pretty easy to say that T. rex was typical, and not some anomalous 110% scavenger evolved solely to make 5-year-olds suffer crushed dreams and cry themselves to sleep.

Yup.

From what I've seen, the Komodo Dragon style "Reasonably badass predator... but hey, if it's dead already, SCORE!" assumptions seem fairly likely.

And the "If Triceratops usually lost, how come they still existed?" question seems a bit silly. One would assume they survived by the usual route. Not getting into fights with gigantic killing machines often, safety in numbers, that sort of thing. Really, there seems to less reason to assume Rex was a wuss than the contrary.

[Oslecamo]

Really, there seems to less reason to assume Rex was a wuss than the contrary.

His wuss little arms speack otherwise. Claws are always nice to help hold /slash your prey. Why did they degenerate so much if the T-Rex was facing big herbivores in a regular basis? Most other big land predators have big claws to help their teeths. The T-Rex can only bring his big head to the fight.

I can totally see in a 10000 years people/aliens finding vulture skeletons and claiming it was some big badass "death from above" flying predator because of it's huge carnivorous beak.

[Volkov]

His wuss little arms speack otherwise. Claws are always nice to help hold /slash your prey. Why did they degenerate so much if the T-Rex was facing big herbivores in a regular basis? Most other big land predators have big claws to help their teeths. The T-Rex can only bring his big head to the fight.

I can totally see in a 10000 years people/aliens finding vulture skeletons and claiming it was some big badass "death from above" flying predator because of it's huge carnivorous beak.

That's all they need, their bite is so deadly it can kill more or less any animal it fancies.

[Kaiyanwang]

His wuss little arms speack otherwise. Claws are always nice to help hold /slash your prey. Why did they degenerate so much if the T-Rex was facing big herbivores in a regular basis? Most other big land predators have big claws to help their teeths. The T-Rex can only bring his big head to the fight.

I can totally see in a 1000 years people finding vulture skeletons and claiming it was some big badass flying predator because of it's huge carnivorous beak.

Well, I'd to see current studies because my knowledge about the issue is outdated, but, as far as I know, maybe the beast worked on the short distance and on the impact.

Even liions are quite fast in short range, maybe it's something like that. I realize that this is my second example with pack animals.

One should see things like the way eyes are placed in the cranium and similar to recognize an hunter, IIRC..

[Drakyn]

His wuss little arms speack otherwise. Claws are always nice to help hold /slash your prey. Why did they degenerate so much if the T-Rex was facing big herbivores in a regular basis? Most other big land predators have big claws to help their teeths. The T-Rex can only bring his big head to the fight.

I can totally see in a 10000 years people/aliens finding vulture skeletons and claiming it was some big badass "death from above" flying predator because of it's huge carnivorous beak.

Degenerated arms are pretty common among larger therapods. Are you claiming that the tendency over millions of years for almost all large predatory dinosaurs was to become and stay almost pure scavengers? T. rex's arms were unusually small even by their standards, but pretty much nobody in its weight class looked like they were pumping iron.

EDIT: Elaborating on the above, the last I also heard of T. rex hunting theory was something like this:
-Charge prey from ambush, slam full weight of body behind jaws, puncturing bone.
-Back off, in the process dragging teeth through the bone. Wait for shock and blood loss to set in.

The process doesn't really need arms. The big head, as you pointed out, is so overdeveloped that it's rendered the need for them obsolete.

[Volkov]

In T.rex's range there are no other large predators to scavenge from, thus scavenging is unfeasible (the raptors present were too small to kill anything big enough to feed rex on a regular enough basis for a fair sized population.)

[Kaiyanwang]

In T.rex's range there are no other large predators to scavenge from, thus scavenging is unfeasible (the raptors present were too small to kill anything big enough to feed rex on a regular enough basis for a fair sized population.)

Well, I can't cite the source because is on one book I say away from at moment, but there are skeletons of big herbivores retrieved together with velociraptor skeletons.

Of course, they could have been gathered by a flood or something similar... as I said, I've been AFD (away from dinos) for a long time..

[Rappy]

EDIT: Elaborating on the above, the last I also heard of T. rex hunting theory was something like this:
-Charge prey from ambush, slam full weight of body behind jaws, puncturing bone.
-Back off, in the process dragging teeth through the bone. Wait for shock and blood loss to set in.

The process doesn't really need arms. The big head, as you pointed out, is so overdeveloped that it's rendered the need for them obsolete.
The alternative current hunting theory goes like this:

Gracile subadults startle prey and chase them toward the robust adult.
Acting like a pack of wolves, the subadults nip and prod at the prey item long enough for the nearby adult to use its full force to deliver the killing blow.


Both ideas seem rather sound from a biological standpoint.

[Starbuck_II]

I'm still wondering why no one shows Dinos with Feathers since T-Rex had them.

[Drakyn]

The alternative current hunting theory goes like this:

Gracile subadults startle prey and chase them toward the robust adult.
Acting like a pack of wolves, the subadults nip and prod at the prey item long enough for the nearby adult to use its full force to deliver the killing blow.


Both ideas seem rather sound from a biological standpoint.

That IS neat. So how firm is the thinking on the pack thing nowadays then? Likely? Possible? Over 50%?

[Kiero]

Actually, Big T was a hunter first, but it had no issue with scavenging, either.

Just like a bear.

[Kaiyanwang]

I'm still wondering why no one shows Dinos with Feathers since T-Rex had them.

So, I have to explicitly say that birds have feathers, now :smallwink:?

[faceroll]

Just like a bear.

Polar bears are the only bears that are entirely carnivorous. Brown bears, grizzlies, and black bears are total omnivores. They are certainly predators, but calling them a "hunter first" is wrong. They aren't that great at hunting, compared to real hunting animals, like canines or felines. I'd consider bears opportunists, not hunters.

[edit]
Canines as in dogs. I guess bears are considered caniformes.

[Oslecamo]

That IS neat. So how firm is the thinking on the pack thing nowadays then? Likely? Possible? Over 50%?

I would say pretty low. Only wolves and humans do something so sophisticated, and wolves are damn smart compared to other animals.

Plus, it's the fact that they're so smart that allows them to kill much bigger and stronger prey. Just like us humies. Wolves will even gank the mighty bear if given the oportunity.

No wonder we ended up togheter.

But the T-Rex, being pretty big, points out to a solitary predator.

[Volkov]

I'm still wondering why no one shows Dinos with Feathers since T-Rex had them.

Adult T.rexes had scaly skin, babies had feathers.

[Volkov]

I would say pretty low. Only wolves and humans do something so sophisticated, and wolves are damn smart compared to other animals.

Plus, it's the fact that they're so smart that allows them to kill much bigger and stronger prey. Just like us humies. Wolves will even gank the mighty bear if given the oportunity.

No wonder we ended up togheter.

But the T-Rex, being pretty big, points out to a solitary predator.

Giganotosaurus was big and a pack hunter, so you're argument falters.

[faceroll]

I would say pretty low. Only wolves and humans do something so sophisticated, and wolves are damn smart compared to other animals.

Plus, it's the fact that they're so smart that allows them to kill much bigger and stronger prey. Just like us humies. Wolves will even gank the mighty bear if given the oportunity.

No wonder we ended up togheter.

My gf recently got two budgies. I've never lived with birds before, and for something with a brain about the size of my molar, they are impressively intelligent. I don't find it far fetched for an ancestral therapod being as smart as a dog, seeing as how their contemporaries are probably the second smartest creatures in the world.

[Volkov]

My gf recently got two budgies. I've never lived with birds before, and for something with a brain about the size of my molar, they are impressively intelligent. I don't find it far fetched for an ancestral therapod being as smart as a dog, seeing as how their contemporaries are probably the second smartest creatures in the world.

Kea parrots are estimated to be as smart as bonobo chimpanzees who are, with the possible exception of whales and/or elephants, the smartest non-hominids on earth.

[lsfreak]

My gf recently got two budgies. I've never lived with birds before, and for something with a brain about the size of my molar, they are impressively intelligent. I don't find it far fetched for an ancestral therapod being as smart as a dog, seeing as how their contemporaries are probably the second smartest creatures in the world.

It's a far stretch to compare budgies to T-rex. Considering the difference in time and the disjointed familial relations (birds descended from a branch of theropods rather distantly related to T-rex), you might as well say you wouldn't be surprised if groundhogs were as smart as humans.
Exaggeration yes, but the comparison is still very stretched.

[Starbuck_II]

Adult T.rexes had scaly skin, babies had feathers.

I'm unsure that the adults lost them:
See even a cousin of T-Rex: http://news.nationalgeographic.com/news/2004/10/1006_041006_feathery_dino.html

[The Glyphstone]

Now...which would be more awesome - 30-ton giant carnivorous prehistoric budgies, or miniature t-rexes that you could keep as cage pets?

[Drakyn]

I would say pretty low. Only wolves and humans do something so sophisticated, and wolves are damn smart compared to other animals.

Plus, it's the fact that they're so smart that allows them to kill much bigger and stronger prey. Just like us humies. Wolves will even gank the mighty bear if given the oportunity.

No wonder we ended up togheter.

But the T-Rex, being pretty big, points out to a solitary predator.

African cape dogs, hyenas, lions, chimpanzees, dolphins and killer whales, and the dhole are some of the pack hunters I can think of off the top of my head. The ability to hunt in a group isn't that uncommon. That giganatosaurus example mentioned earlier has more evidence for pack hunting than T. rexes, and they were both dumber and even bigger.

[Oslecamo]

My gf recently got two budgies. I've never lived with birds before, and for something with a brain about the size of my molar, they are impressively intelligent. I don't find it far fetched for an ancestral therapod being as smart as a dog, seeing as how their contemporaries are probably the second smartest creatures in the world.


Brain size does not matter!

Seriously, that has been proved for something like a century now. There's no direct relation between the volume of a brain and it's capacity.

For example, crows and magpies have been recently considered some of the smartest beings on Earth right after us. Heck, some of them beat universitary students in logic tests.

Now pick the blue whale. Biggest brain in the planet. But dumb enough to let killer whales nib it to death whitout trying to defend itself. Much more dumb than a dolphin that's for sure, despite it's brain being several degrees bigger.

Now pick up a chicken. Or dodo. Or turkey. Dumb. Really dumb.

Drakyn:Wolves are the best at pack hunting. There's a world of diference between simple zerg tactics (surround and attack untill it's dead) to the complex ambushes and diversions wolves use. It's like comparing a mob of peasants to a roman legion. Both know that numbers have the advantage, but the second does it much better.

[faceroll]

Kea parrots are estimated to be as smart as bonobo chimpanzees who are, with the possible exception of whales and/or elephants, the smartest non-hominids on earth.

The smartest animal ever recorded being smart was an african grey. Cetaceans could definitely be super smart, but they're too busy having fun in the wild to show off their powerful intellects.


It's a far stretch to compare budgies to T-rex. Considering the difference in time and the disjointed familial relations (birds descended from a branch of theropods rather distantly related to T-rex), you might as well say you wouldn't be surprised if groundhogs were as smart as humans.
Exaggeration yes, but the comparison is still very stretched.

Fair enough. Though I think it would be more helpful to think of that dinosaur clade as birds, rather than big dumb slow lizards, which is what most of us grew up with. There's no reason to think that therapods were stupid or incapable of hunting together. As diurnal social predators, you'd expect them to be at least kind of smart.



Brain size does not matter!

Seriously, that has been proved for something like a century now. There's no direct relation between the volume of a brain and it's capacity.

For example, crows and magpies have been recently considered some of the smartest beings on Earth right after us. Heck, some of them beat universitary students in logic tests.

Now pick the blue whale. Biggest brain in the planet. But dumb enough to let killer whales nib it to death whitout trying to defend itself. Much more dumb than a dolphin that's for sure, despite it's brain being several degrees bigger.

So on what evidence have you concluded that t-rex was dumb, if not for its relatively small brain? Your unfamiliarity with animal behavior?

[Volkov]

It's a far stretch to compare budgies to T-rex. Considering the difference in time and the disjointed familial relations (birds descended from a branch of theropods rather distantly related to T-rex), you might as well say you wouldn't be surprised if groundhogs were as smart as humans.
Exaggeration yes, but the comparison is still very stretched.

Tyrannosaurs are coeluerosaurs, and birds are all in fact Coeluerosaurs.

[lsfreak]

I would like to bring up that while raw size doesn't matter, there are correlations when you look at the ratio of brain sizes in similar species. If two species both have a brain of mass x, but one of them is half the size of the other, it's likely the smaller one is comparatively smarter, or at least one aspect is radically more developed.

I'll also bring up that, as has been said already, evolution has pretty made everything smarter. While a T-rex may have been the genius of the animal world during it's time, comparisons to modern animals have no place. It would be similar to saying that that groups of people 25,000 years ago were complex - while that may be true of the time, comparisons with modern complexity are out of place. Don't jump to conclusions about intelligence or behavior based on modern animals, because there are staggering differences.

[faceroll]

I'll also bring up that, as has been said already, evolution has pretty made everything smarter. While a T-rex may have been the genius of the animal world during it's time, comparisons to modern animals have no place. It would be similar to saying that that groups of people 25,000 years ago were complex - while that may be true of the time, comparisons with modern complexity are out of place. Don't jump to conclusions about intelligence or behavior based on modern animals, because there are staggering differences.

How do we know this? The only difference between a human now and a human 25kya is cultural, except probably some micro evolution in the MHC and related systems. "Evolution makes things smarter" is so early 20th century. Evolution also makes things much, much dumber. There's really no convincing argument that over the past 60mys, everything magically got smarter. In the 300mys of Diapsid evolution, why couldn't smartness have showed up 200mys ago, instead of 60?

[Drakyn]

Wolves are the best at pack hunting. There's a world of diference between simple zerg tactics (surround and attack untill it's dead) to the complex ambushes and diversions wolves use. It's like comparing a mob of peasants to a roman legion. Both know that numbers have the advantage, but the second does it much better.

The tactic being proposed for Tyrannosaurus was simply "littler guys flush the prey into the big guys," which is scarcely the pinnacle of advanced strategy. It isn't being said that T. rex are super geniuses, just that they may possibly have hunted in a pack - which is what all of my examples do.
Also, at least one of the examples I cited (African Wild/Cape/Hunting Dogs) have the highest known hunting success rate of any predator, so be careful what you label "zerg tactics."

[Beowulf DW]

I would like to bring up that while raw size doesn't matter, there are correlations when you look at the ratio of brain sizes in similar species. If two species both have a brain of mass x, but one of them is half the size of the other, it's likely the smaller one is comparatively smarter, or at least one aspect is radically more developed.

I'll also bring up that, as has been said already, evolution has pretty made everything smarter. While a T-rex may have been the genius of the animal world during it's time, comparisons to modern animals have no place. It would be similar to saying that that groups of people 25,000 years ago were complex - while that may be true of the time, comparisons with modern complexity are out of place. Don't jump to conclusions about intelligence or behavior based on modern animals, because there are staggering differences.

You're forgetting the mass extinction. Modern day birds probably did not descend from T-Rex itself, but most likely a much smaller cousin. Mass Extinctions tend to kill off the largest and the most specialized species, leaving smaller more basic species room to evolve. Some species of dinosaurs may have been as smart as some of the animals around today, but they were probably wiped out before they could evolve further.

[Admiral Squish]

What's with all the feathers? I don't get it. When there was no 'birds' as we know them, what purpose could forelimbs lined with long feathers serve?

[Beowulf DW]

What's with all the feathers? I don't get it. When there was no 'birds' as we know them, what purpose could forelimbs lined with long feathers serve?

Camoflage, purposes associated with mating, shelter from the elements.

It all really depends on the structure and color of the feathers.

[Starbuck_II]

What's with all the feathers? I don't get it. When there was no 'birds' as we know them, what purpose could forelimbs lined with long feathers serve?

Well, what purpose are long sleeve shirts? Protection from the elements.

That is why birds use feathers: keep warm, water protection (well the oils they secrete help too), etc.

[nightwyrm]

What's with all the feathers? I don't get it. When there was no 'birds' as we know them, what purpose could forelimbs lined with long feathers serve?

It is almost certain that feathers evolved for purposes such as warmth, camoflague etc. before being subsequently adapted for flight.

[faceroll]

What's with all the feathers? I don't get it. When there was no 'birds' as we know them, what purpose could forelimbs lined with long feathers serve?

My guess would be they'd serve largely social functions. Birds have incredible vision, because they had diurnal ancestors (the dinosaurs). Us mammals have relatively poor vision, because we spent the better part of the past 300mys mucking about in the dark as tiny, terrified proto-rodents, and lost most of our color vision (primates re-evolved some of it, though). This is why modern birds are so splendid in color and patterning- they are HIGHLY visual creatures, so they communicate with their feathers.

Besides flight and insulation, bird feathers are also used for hiding and communication. They also reflect light on the ultraviolet spectrum, so even dully colored birds aren't that dully colored if you can see ultraviolet (like birds can).

[chiasaur11]

I'm still wondering why no one shows Dinos with Feathers since T-Rex had them.

Where'd you get that idea?

None of my (admittedly limited) research suggests that, and to the contrary, it seems like the preserved scaly hide would indicate a lack.

Relatives of the tyrant king had them, sure, but the star of dinosaur comics hisself?

Nope.

Although he did have 3 fingers a hand. Just one was very tiny.

[vicente408]

A healthy adult triceratops would have no problem at all fending off a tyrannosaurus. It has as much mass as a T-rex, but is about half the size, and has a much lower center of gravity. That along with the arrangement of its limbs (straight in back, splayed out it front) make it incredibly difficult to move around. Its most vulnerable region, the neck, is protected by a frill made of several inches of solid bone covered in another couple inches of fingernail-like material. For offense, its horns are several feet long and a foot thick at the base, also made of solid bone. Most importantly, triceratops had a unique adaptation in its skeleton; its skull connects to its body with a ball-and-socket joint, which allowed it to swivel its head in nearly any direction very rapidly. If a triceratops was aware of the predator, there is almost no way you could get to it without being intercepted by its goring horns. T-rex's only hope would be an ambush, or to go after a sick/dying/child. Only the most desperate hunter would go after such a thing when easier prey is most certainly available.

[hamishspence]

Given that there are healed bite marks on at least one Triceratops specimen (with a broken horn) this would suggest that there must have been some interaction between the two.

Triceratops's bony frill is quite unusual in ceratopsians- most had holes in their frills, and some had very large holes which meant the frill would have provided little protection.

Its possible that T. rex would have attacked young or sick specimens by preference (this is usual for predators) but the idea that binocular vision, long legs, great size, etc all represent scavenging specialisms, seems a little implausible to me.

[faceroll]

Given that there are healed bite marks on at least one Triceratops specimen (with a broken horn) this would suggest that there must have been some interaction between the two.

Triceratops's bony frill is quite unusual in ceratopsians- most had holes in their frills, and some had very large holes which meant the frill would have provided little protection.

Its possible that T. rex would have attacked young or sick specimens by preference (this is usual for predators) but the idea that binocular vision, long legs, great size, etc all represent scavenging specialisms, seems a little implausible to me.

I keep thinking of the t rex like a prehistoric bear, but the teeth are all wrong for being omnivorous.

What about eating fish? Bears, especially brown bears, get huge amounts of nutrition from eating yearly fish runs. Their size helps them store all that food for a long time and prevents other animals from stealing it.

[hamishspence]

Spinosaurs are a far closer analogue for Dino-Bear- long arms, fossil fish scales found inside the ribcage (suggesting a diet that at least included fish)- etc.

On T. rex- this site answers most of the "It was 100% scavenger" arguments by Jack Horner:

http://www.gavinrymill.com/dinosaurs/t-rex-hunter-of-scavenger.html

That doesn't necessarily prove it was a hunter- just that the "scavenger" arguments aren't entirely convincing.

[ericgrau]

How big was your lunch today?? Normally predators don't hunt anything as large as them, at least not alone. EDIT: And don't forget HD advancement. A larger, advanced T-Rex may well go after younger prey.

[multilis]

"Pack hunting" - even insects such as ants can have a form of pack hunting, simplistic form can be like shark "if smell blood then join in".

In my opinion very hard to tell intelligence of something like a dino, animals like chickens and sheep can sometimes do fairly complex automated behavior even after they lose their heads when butchered, a very large animal may have more automation regulated to nerves with the relatively small central processing unit focusing on the big picture, *or* most of the brain was consumed with simple automation. Even small brains of insects sometimes do amazingly complex things, often as a team.

[hamishspence]

Pack hunters do- Mapusaurus, an allosaur of comparable size to T.rex, is suspected to be a pack hunter (from a bonebed of animals of mixed size).

Killer whale pack vs baleen whale might be comparable to T.rex group vs Alamosaurus- both prey animals have a dangerous tail attack- but the predators are still capable of winning.

Even among solitary predators, there are cases of predators specializing in hunting prey larger than them.

Tigers hunt buffalo several times their weight- weasels hunt rabbits, Carcharodon Megalodon hunted whales, and so on.

Also:


Although he did have 3 fingers a hand. Just one was very tiny.

From this dinosaur textbook site:

http://www.geol.umd.edu/~tholtz/dinoappendix/

Chapter 17: Tyrannosauroids (Tyrant Dinosaurs)
NEW January 2008: Last year there were many news reports about the finding that Tyrannosaurus rex "had three fingers". Unfortunately, those reports were not correct. In fact, the real find was a well-preserved third metacarpal (long bone of the palm of the hand) for T. rex: nota surprise as these were already known in other two-fingered tyrannosaurids. In fact, you can see this little bone on the hand skeleton of Tyrannosaurus on the bottom of page 120

[The Glyphstone]

How big was your lunch today??


Wind blows through the air, tinged with the faint smell of an old sock that someone left in the air conditioner last week...

Padding silently on sock-covered feet, homo sapiens nerdicus prowls towards its prey, lying unsuspecting and undefended in the middle of the Kitchen Counter Plains. The half-open door gives cover for the final stalk, watching the impending victim sit oblivious. A few steps forward, a sudden rush, and a pounce!

Victorious, the hungry predator scuttles back into its basement lair to feast, the limp and faintly crinkling body of the Doritosaurus clenched in its jaws...

[Admiral Squish]

Wind blows through the air, tinged with the faint smell of an old sock that someone left in the air conditioner last week...

Padding silently on sock-covered feet, homo sapiens nerdicus prowls towards its prey, lying unsuspecting and undefended in the middle of the Kitchen Counter Plains. The half-open door gives cover for the final stalk, watching the impending victim sit oblivious. A few steps forward, a sudden rush, and a pounce!

Victorious, the hungry predator scuttles back into its basement lair to feast, the limp and faintly crinkling body of the Doritosaurus clenched in its jaws...
I loled.:smallbiggrin:

[hamishspence]

One of the things I've noticed, is that more recent research does tend to support the idea it was fast, quite light for its size, etc:

http://www.telegraph.co.uk/science/dinosaurs/4884881/Tyrannosaurus-Rex-was-a-lean-mean-hunter.html

Also- mmm, doritosaurus... :smallbiggrin:

[LichPrinceAlim]

Wind blows through the air, tinged with the faint smell of an old sock that someone left in the air conditioner last week...

Padding silently on sock-covered feet, homo sapiens nerdicus prowls towards its prey, lying unsuspecting and undefended in the middle of the Kitchen Counter Plains. The half-open door gives cover for the final stalk, watching the impending victim sit oblivious. A few steps forward, a sudden rush, and a pounce!

Victorious, the hungry predator scuttles back into its basement lair to feast, the limp and faintly crinkling body of the Doritosaurus clenched in its jaws...

I need a fresh pair of drawers....

[absolmorph]

Calvin and Hobbes, of course. :smallsmile:
It can be found in There's Treasure Everywhere, one of the books.
The back cover and page 128, to be specific.
-just checked-

[Yakk]

A better way to look at it is what happens when a predator is able to defeat adult instances of all of its possible prey, which is non-stealthy.

Then a lean year comes.

The predator kills anything that cannot hide to stay alive. And the brontosaurus goes extinct, followed by the predator.

In general, prey must win the battle of prey vs predator most of the time. If it doesn't, the predator is likely to ramp up in reproduction rate (which, of course, is an adaptive strategy within a population) until it wipes out the prey.

In the case of things like rabbits, they hide underground, which lets them win the prey vs predator fight against foxes most of the time. In the case of Brontosaurus-type critter, the only way (ecologically) that the T. Rex and Brontosaurus-type critter could mutually survive in an environment is that the Brontosaurus-type critter must be able to keep the T. Rex at bay.

Even today, Lions prey on Water Buffalo, which usually win the predator vs prey game against Lions. Lions attack the sick and elderly Buffalo, because if they attack the young and healthy ones (in their natural, herd-sized environment, naturally), the return on investment is negative. If it was positive, Lions would do it, and shortly there wouldn't be many Buffalo left, and then (and only then) the Lions would starve (or start eating some prey they cannot effectively wipe out, which we would (because we are talking historical scales) would think of as the Lions "natural" prey).

[faceroll]

A better way to look at it is what happens when a predator is able to defeat adult instances of all of its possible prey, which is non-stealthy.

Then a lean year comes.

The predator kills anything that cannot hide to stay alive. And the brontosaurus goes extinct, followed by the predator.

In general, prey must win the battle of prey vs predator most of the time. If it doesn't, the predator is likely to ramp up in reproduction rate (which, of course, is an adaptive strategy within a population) until it wipes out the prey.

In the case of things like rabbits, they hide underground, which lets them win the prey vs predator fight against foxes most of the time. In the case of Brontosaurus-type critter, the only way (ecologically) that the T. Rex and Brontosaurus-type critter could mutually survive in an environment is that the Brontosaurus-type critter must be able to keep the T. Rex at bay.

Even today, Lions prey on Water Buffalo, which usually win the predator vs prey game against Lions. Lions attack the sick and elderly Buffalo, because if they attack the young and healthy ones (in their natural, herd-sized environment, naturally), the return on investment is negative. If it was positive, Lions would do it, and shortly there wouldn't be many Buffalo left, and then (and only then) the Lions would starve (or start eating some prey they cannot effectively wipe out, which we would (because we are talking historical scales) would think of as the Lions "natural" prey).

Only if evolution acts for one brief, singular moment on a singular species. Otherwise it's a red queen scenario, or the predator develops a taste for something else.

[Ormagoden]

Just like a bear.

Did somebody say bear?

[hamishspence]

Hmm- is the increasing size of tyrannosaurs and their prey, a "red queen scenario" involving size? That is, with both experiencing selection pressure to be larger?

[Yakk]

or start eating some prey they cannot effectively wipe out, which we would (because we are talking historical scales) would think of as the Lions "natural" prey
Only if evolution acts for one brief, singular moment on a singular species. Otherwise it's a red queen scenario, or the predator develops a taste for something else.
I don't understand. How is "the predator develops a taste for something else" different than "start eating some prey they cannot effectively wipe out"?

[chiasaur11]

Chapter 17: Tyrannosauroids (Tyrant Dinosaurs)
NEW January 2008: Last year there were many news reports about the finding that Tyrannosaurus rex "had three fingers". Unfortunately, those reports were not correct. In fact, the real find was a well-preserved third metacarpal (long bone of the palm of the hand) for T. rex: nota surprise as these were already known in other two-fingered tyrannosaurids. In fact, you can see this little bone on the hand skeleton of Tyrannosaurus on the bottom of page 120

Ahem.

Oh. Mildly disappointing. Ah, well.

[Serpentine]

I would say pretty low. Only wolves and humans do something so sophisticated, and wolves are damn smart compared to other animals.Lions, for one, have a "one group hangs around downwind, another group comes from upwind into the ambush" technique, as do dolphins and I'm pretty sure various other predators.
I don't find it far fetched for an ancestral therapod being as smart as a dog, seeing as how their contemporaries are probably the second smartest creatures in the world.Dolphins have been upgraded to "2nd-cleverest animal after humans", knocking down chimpanzees (and/or other apes?).


What's with all the feathers? I don't get it. When there was no 'birds' as we know them, what purpose could forelimbs lined with long feathers serve?There's a few theories. Body heat regulation would be one, but there's also that they might allow a dinosaur to leap higher or further, or that it assists gliding/slowing a fall from a high place.


Given that there are healed bite marks on at least one Triceratops specimen (with a broken horn) this would suggest that there must have been some interaction between the two.Of course, the fact that they healed also suggests that the Triceratops won out.

Triceratops's bony frill is quite unusual in ceratopsians- most had holes in their frills, and some had very large holes which meant the frill would have provided little protection.I find it hard to believe that anything but the largest of holes would prevent the frill from being at least significant protection. Don't forget: even stopping an attempt at an attack can be at least as good as stopping an attack from being fatal.

For the record, I've never said that t-rexes would only be scavengers, only that - like modern predators - they would be making careful risk assessments and targetting easier prey (aka sick/injured/young). And, of course, that few modern predators would give up a free pre-dead meal. In fact, I think the only such creatures I can think of are things like snakes and frogs, that can't actually detect non-live prey...
Also, I'm pretty sure "there weren't any other predators to scavange off" (debatable - we've only found a fraction of species that would have existed, for one) is a very flawed argument. There are lots and lots of other ways for animals to die - disease, parasites, starvation, birth defects, injury, accident, general weakness...

[Amiel]

Herbivores lead a primarily sedentary lifestyle; as this implies, little to no activity is necessary. Their method of food extraction, grazing, allows them to remain in one place and in one position for long periods. Even when standing they can also be sitting. This allows them to place greater mass on their body, hence their often prodigious sizes.

Carnivores, on the other hand, are primarily active hunters. Even the scavengers have to be able to run quickly and over distances. To catch their prey and not starve to death, they cannot afford to be lumbering beasts.
Even quadrupedal carnivores tend to be smaller than their herbivore peers.

Their size interrelates to the food they eat.

[Dr Bwaa]

At least, until Advancement: F-14s comes into play.

Win. Win, win, win. :smallamused:

Secondly-- herbivores are freaking tanks. Ankylosaurus has eyelids made of bone, 8-inch thick armor, and a 100-to-200-pound tail club that could swing at upwards of 40mph. Triceratops horns are over a foot thick at the base, and the "shield" is nearly as sturdy--all solid bone (compare to rhino horns, which are made of hair). Yeah, a Tyrannosaurus has a seriously hardcore bite, but an actual fight with these herbivores is something to be avoided at all costs--even if you kill it, maybe you get hurt or lose a leg, and that means you die, too (of course, that argument doesn't apply in D&D terms :smalltongue:).

[TheDarkOne]

Dolphins have been upgraded to "2nd-cleverest animal after humans", knocking down chimpanzees (and/or other apes?)

I'm extremely sceptical of this claim. I'm not even sure how you would go about deciding on some sort of absolute measure of intelligence in animals. This is even a difficult thing to judge between members of the same species. Part of the problem would be that to varying degrees the brains of different animals will be specialized for different things. So you could come up with a measure where one species would do better than the other, and then come up with another measure where the reverse would be true.

I think all you can say with any certainty is that they're both very smart animals.

[Serpentine]

I'm extremely sceptical of this claim. I'm not even sure how you would go about deciding on some sort of absolute measure of intelligence in animals. This is even a difficult thing to judge between members of the same species. Part of the problem would be that to varying degrees the brains of different animals will be specialized for different things. So you could come up with a measure where one species would do better than the other, and then come up with another measure where the reverse would be true.

I think all you can say with any certainty is that they're both very smart animals.I think animal psychologists would be the very first to admit this. The very fact that the artificial ranking is constantly shifting is evidence of it. But, humans being what we are, we like to rank things, and the people studying animal intelligence are no exception to this. Nonetheless, such a ranking would be secondary to their actual work in animal cognition.

Some (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1868071/) of the (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VH9-3SX0DHN-P&_user=1047984&_coverDate=07%2F31%2F1997&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1228547029&_rerunOrigin=scholar.google&_acct=C000050931&_version=1&_urlVersion=0&_userid=1047984&md5=b7ca374780f86514ec6caadfc6912278) studies (http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowAbstract&ArtikelNr=000006540&Ausgabe=224648&ProduktNr=223831) from whence this conclusion came. You can judge their methods and definitions for yourself.

[Beleriphon]

(compare to rhino horns, which are made of hair)

Correction, a rhino horn is composed of keratin (http://en.wikipedia.org/wiki/Keratin) which is a dense, very touch protein strain that forms polymer like bonds, which happens to be the same stuff that hair is formed from. Its also the same stuff that tortoise shells, bird beaks, and most animals claws are made of. I'd imagine that a triceratops' frill and horns are also formed of keratin, the stuff does fossilize pretty well.

Having any horn or protective item exposed and formed of bone is a bade idea. Bone is prone to infection, and a bond infection is bad mojo. Really bad mojo. Keratin on the other hand is an inert polymer and can form extremely strong bonds, and can form very sharp edges.

[Dr Bwaa]

Correction, a rhino horn is composed of keratin (http://en.wikipedia.org/wiki/Keratin) which is a dense, very touch protein strain that forms polymer like bonds, which happens to be the same stuff that hair is formed from. Its also the same stuff that tortoise shells, bird beaks, and most animals claws are made of. I'd imagine that a triceratops' frill and horns are also formed of keratin, the stuff does fossilize pretty well.

Yes, yes, but it sounds much more impressive (well, less, actually) to say "hair." But not so for Triceratops, all that frill and horn is honest-to-goodness bone (http://animals.howstuffworks.com/dinosaurs/triceratops.htm) (links to an example (sixth paragraph under the second picture, eg.); wikipedia, Discovery, etc corroborate).

[Beleriphon]

Yes, yes, but it sounds much more impressive (well, less, actually) to say "hair." But not so for Triceratops, all that frill and horn is honest-to-goodness bone (http://animals.howstuffworks.com/dinosaurs/triceratops.htm) (links to an example (sixth paragraph under the second picture, eg.); wikipedia, Discovery, etc corroborate).

I gotcha, the frill is part of the skull. Although I'd expect the horns to be keratin, especially if they were used defensively, or in fighting (akin to bighorn sheep fights). I'd generally assume anything no directly covered in skin to be made of keratin, or chitin. Although the later is far more common in arthropods.

[Admiral Squish]

I gotcha, the frill is part of the skull. Although I'd expect the horns to be keratin, especially if they were used defensively, or in fighting (akin to bighorn sheep fights). I'd generally assume anything no directly covered in skin to be made of keratin, or chitin. Although the later is far more common in arthropods.

From the sound of my (limited) research, we're looking at a bone core and a keratin covering.

[TheDarkOne]

I think animal psychologists would be the very first to admit this. The very fact that the artificial ranking is constantly shifting is evidence of it. But, humans being what we are, we like to rank things, and the people studying animal intelligence are no exception to this. Nonetheless, such a ranking would be secondary to their actual work in animal cognition.

Some (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1868071/) of the (http://www.sciencedirect.com/science?_ob=ArticleURL&_udi=B6VH9-3SX0DHN-P&_user=1047984&_coverDate=07%2F31%2F1997&_rdoc=1&_fmt=high&_orig=search&_sort=d&_docanchor=&view=c&_searchStrId=1228547029&_rerunOrigin=scholar.google&_acct=C000050931&_version=1&_urlVersion=0&_userid=1047984&md5=b7ca374780f86514ec6caadfc6912278) studies (http://content.karger.com/ProdukteDB/produkte.asp?Aktion=ShowAbstract&ArtikelNr=000006540&Ausgabe=224648&ProduktNr=223831) from whence this conclusion came. You can judge their methods and definitions for yourself.


Those paper's don't seem to be about ranking intelligence at all, their certainly studying intelligence in animals, but they never seek to establish an absolute rating system. I'd bet dollars to doughnuts that if you asked the authors of the papers "So, do these conclusions mean dolphins are smarter than chimps?" Their answer would begin with something like "Well, that depends..." or at the most "In my opinion, yes, but..."

[Serpentine]

*shrug* Whatever. They were the basis of (non-scientific) articles announcing that dolphins had been bumped up in the (official or unofficial) "ranking" of animal intelligence that first brought it to my attention. Furthermore, this nitpicking does not negate my own nitpicking regarding the relative intelligence of birds - at this point, below that of humans, other apes, and dolphins, and far from the "second-most intelligent animal". I have no doubt that your prediction of the scientist's response to the question is likely.
edit: Basically, at this point in scientific knowledge, the two main contenders for "most intelligent animal after humans" is apes and dolphins, and recent research has bumped up dolphins in that regard.
Some (http://www.timesonline.co.uk/tol/news/science/article6973994.ece) non-scientific (http://www.groundreport.com/Health_and_Science/Dolphin-Intelligence-Sense-of-Self-Much-Above-Chim_5/2918357) articles (http://derrenbrown.co.uk/blog/2010/01/dolphins-proven-smarter-chimps-humans-intelligence/) of the sort from which I was given the "dolphins are second-most intelligent" fact (the former is where I got the name to try to find an origin paper). It's entirely possible that they misunderstood the conclusions of the scientist/s, or more likely that they exaggerated them and made them more conclusive than they actually were. I promise I'm not pulling this out my arse, though. Inasmuch as there is a rough grading system, dolphins are at least on par with apes.
edit mk. 2: Oh, and you don't have to lecture me about how difficult it is to quantify animal intelligence. Animal Behaviour was one of my best and favourite classes :smallcool: :smalltongue:

[faceroll]

I gotcha, the frill is part of the skull. Although I'd expect the horns to be keratin, especially if they were used defensively, or in fighting (akin to bighorn sheep fights). I'd generally assume anything no directly covered in skin to be made of keratin, or chitin. Although the later is far more common in arthropods.

I'm guessing this is what's leading some scientists to claim that triceratops' horns were for communicating, not fighting.

[hamishspence]

Don't the horns interlock neatly when two model Triceratops skulls are put together?

Its possible the frill was more for display, and the horns for intersocial fighting.

[Volkov]

I wonder why the Albertasaurines completely vanished from the fossil record within mere geological moments after Tyrannosaurus Rex's development from Daspletosaurus. Perhaps the younger Tyrannosaurus's stole their Niche and were better than Gorgosaurus at it's ecological role.

[Oslecamo]

Correction, a rhino horn is composed of keratin (http://en.wikipedia.org/wiki/Keratin) which is a dense, very touch protein strain that forms polymer like bonds, which happens to be the same stuff that hair is formed from. Its also the same stuff that tortoise shells, bird beaks, and most animals claws are made of. I'd imagine that a triceratops' frill and horns are also formed of keratin, the stuff does fossilize pretty well.


If I'm not mistaken, even our nails are made out of keratine. As well as most predator claws, not only

As for the triceratops, some theories sugest that they were more used to impress/atract females than exactly fighting.

Wich doesn't mean they were weak. Just like the peacock's huge useless tail, having big fragile useless bone horns and surviving to adulthood is a sign you're a badass and worthy of reproducing.

[Moglorosh]

Dolphins are (last I heard anyway) the only species besides man to mate for reasons other than reproduction.

They're also one of the few species that kill other animals for no discernible purpose other than to apparently entertain themselves. (The only other species I can think of that kills without needing to is the domestic house cat)

They also have a complex communication system and there's at least one documented case of a dolphin purposefully committing suicide.

If they had thumbs we would probably bow to them.

[Serpentine]

Chimpanzees, bonobos and other animals mate for reasons other than reproduction (not to mention homosexuality in other animals, which for obvious reasons can't be (at least conciously or whatever) for reproductive purposes.
For the hell of it, I'll track down examples.

edit: Ta-da! (http://en.wikipedia.org/wiki/Animal_sexual_behaviour#Sex_for_pleasure)
Also. (http://en.wikipedia.org/wiki/Bonobo#Sexual_social_behavior) Note, non-reproductive reasons and activities listed for bonobos: greeting, conflict resolution, post-conflict reconciliation, oral, homosexuality, celebration, tension relief, social bonding, cementing unity...

Soooo... nyet :smalltongue: Wait, what's the relevance of this, again? :smallconfused:

[Satyr]

I guess you don't count apes as men, and then you are wrong. Take a look at bonobos. Bonobos are basically living in a world created by porn. They do not only use sex as a recreative activity, but have developed a simple form of prostitution, of the "would you sleep with me if I gave you these nice, delicious bananas?" variety. By the way, they ignore gender boundaries for this kind of fun.

Intelligence in animals is difficult to assess, because intelligence is such a diverse umbrella terminology, that includes several, very different abilities. According to the most common definition of intrelligence used today, it is the ability to survive and prosper in the given environment and to develop valid survival strategies. With this definition, any non-extinct species is smarter than the dinosaurs of old. They adapted, and changed.
But, there are still different abilities included in the term of intelligence. The ability to use tools, the ability of self-recognition, the ability of communication, the ability to learn, the ability to count, the ability to adjust known strategies, the ability to plan and find solutions...

there is no animal that comes close to humans in any of these categories, and in several abilities there are different stars. Dogs for example are great learners (and the smartest of all domesticated animals except elephants) but tool use isn't their strength and they are only good in one way communication (meaning understanding). Dolphins are good in many areas, as are most primates.

The other thing is, that there are also individual differences between animals. There are smarter and more stupid individual dolphins, apes, or dogs, as much as there more intelligent and more stupid humans, so it is not always right to make too general claims about their intelligence.

[Anterean]

Wind blows through the air, tinged with the faint smell of an old sock that someone left in the air conditioner last week...

Padding silently on sock-covered feet, homo sapiens nerdicus prowls towards its prey, lying unsuspecting and undefended in the middle of the Kitchen Counter Plains. The half-open door gives cover for the final stalk, watching the impending victim sit oblivious. A few steps forward, a sudden rush, and a pounce!

Victorious, the hungry predator scuttles back into its basement lair to feast, the limp and faintly crinkling body of the Doritosaurus clenched in its jaws...

This is easily the funniest thing I have read all day. Thanks for the laugh

[Oslecamo]

The ability to use tools, the ability of self-recognition, the ability of communication, the ability to learn, the ability to count, the ability to adjust known strategies, the ability to plan and find solutions...


Actualy, it's agreed that the maximum sign of intelegence is being able to build tools from other tools. Something only we humies can do. And it's 99.9% of the reason of our big sucess.

So you've got claws? Well I've got this sharp spear. And fire. So you've got tick fur? Well, let me take your sharp fur, put conservants and then wear it myself. So you're flying? Say hello to "bows". So you're in the sea? Say hello to "boats". And so on.

This is, remove the tools from an humie and what have you got left? A hairless primate wich the ony thing he can do well is walking for long hours.


Sure, the rest of the stuff you mention also helps and shows some intelegence, but they can be teached. To pretty much every animal. Building usefull stuff, now that's what's really admired.

[Drogorn]

This is, remove the tools from an humie and what have you got left? A hairless primate wich the ony thing he can do well is walking for long hours.

And invent tools. That big rock over there? Tool. That stick? Tool. Find another stick? Use both sticks and you have fire.

You see, you can't take tools away from a human because they'll just make more. Heck, prisoners have made firearms.

One other thing. Humans can indeed walk for long hours. Longer than pretty much anything else. This means that humans can chase down prey, then kill and eat them. Humans are the pinnacle endurance predator, tools just add to that.

[Drakyn]

That's nothing. We can leap tall buildings in a single bound, have enormous genitalia for our size, possess dexterous hands, can see through walls, can fly around the planet so fast we travel back in time, become an analogue for perfection in every way while wearing a silly pair of tights, and invent thousands and thousands of fictional beings and worlds that exist only to tell us these things over and over until you'd think our spines would be sore from fellating ourselves, although that's probably because they're not properly and fully adapted to bipedalism which doesn't matter because we are SO AWESOME.

Also, we could totally beat up the rest of the planet's dads http://i.somethingawful.com/forumsystem/emoticons/emot-smug.gif

[Oslecamo]

And invent tools. That big rock over there? Tool. That stick? Tool. Find another stick? Use both sticks and you have fire.

You'll notice that that is using tools to produce other tools. No other animal can do that.

And it would have been much easier if you had brought your fire-making kit. Because that lion over there won't exactly wait for you to find sticks and rub them togheter.

The natives of Easter island basicaly commited suicide when they burned most of the wood on their island. Then they didn't even have enough sticks to build a boat to escape!



You see, you can't take tools away from a human because they'll just make more. Heck, prisoners have made firearms.

And what was the last time you saw prisoners beating the security guards with armor and better made weapons? It may have hapened some times, but as a rule of thumb, the side with better tools wins. Spears beat unharmed. Bows beat spears. Heavy armor beats bows. Guns beat heavy armor.



One other thing. Humans can indeed walk for long hours. Longer than pretty much anything else. This means that humans can chase down prey, then kill and eat them. Humans are the pinnacle endurance predator, tools just add to that.

Except when the prey disapears out of sight (like in forests). Also, good luck beating down even a weakened antilope with your bare hands.

[Ravens_cry]

Except when the prey disapears out of sight (like in forests). Also, good luck beating down even a weakened antilope with your bare hands.
Humans would have had to do just that before they invented spears. And humans come from savannah. Savannah, by definition have an open canopy at most. Running in to a thick forest isn't an option for Mr. Antelope.

[Oslecamo]

Humans would have had to do just that before they invented spears. And humans come from savannah. Savannah, by definition have an open canopy at most. Running in to a thick forest isn't an option for Mr. Antelope.

Hey, where do you think we got our super legs? They didn't just drop from the sky indeed. It was a natural adaptation to our enviroment.


Meanwhile the other primates specialized in tree climbing. Wich meant soon they couldn't go to any place that didn't have tick forest. The fools... While we expanded trough deserts and mountains and whatnot.

But anyway, just because you can chase an antelope to death in the Savannah doesn't really mean that tactic will work everywhere.

I always prefered the "Chase them untill they fall down from a cliff" personally. This is, how dumb can those horses be? They're not going to jump to their deaths are they? Oh, wait they are. Free meat!

[Satyr]

Actualy, it's agreed that the maximum sign of intelegence is being able to build tools from other tools. Something only we humies can do. And it's 99.9% of the reason of our big sucess.

This might be a very anthropomorphic perspective, (because we use tools and we are awesome, tool use is awesome, and thus means you are extra smart), but yes, there is a strong hint that manual dexterity has a great impact on overall intelligence (just compare octopi with snails), but it is not as much an ability in itself, but a proof for the actual ability: a complex problem solution mechanism and adaptation, combined with the transfer of of something you already know to something completely new (this is basically what you need to build any tool that is more advanced than a club).


One other thing. Humans can indeed walk for long hours. Longer than pretty much anything else. This means that humans can chase down prey, then kill and eat them. Humans are the pinnacle endurance predator, tools just add to that.

I am not quite sure if canides are not a bit better in this, but yes, it's good to be human. And besides, we own the canides anyway. And do it for a long, long time. Much for their and our rejoicing.
This is an actual point: Domestication and as such an enforced symbiosis is basically the use of other creatures as a tool.

[Ravens_cry]

Hey, where do you think we got our super legs? They didn't just drop from the sky indeed. It was a natural adaptation to our enviroment.

Another adaptation is swimming. Which allowed us to ford rivers and lakes as we migrated across the landscape in a world before tools.


Meanwhile the other primates specialized in tree climbing. Wich meant soon they couldn't go to any place that didn't have tick forest. The fools... While we expanded trough deserts and mountains and whatnot.
Yeah, Humans are Badass. Badass nerds with legs of steel that keep coming and coming and coming and analyse their environment for the best strategies to survive, even in places far removed from our original biome.
Humans are Batman!
***
I look up at the stars and I think one thing.
We're coming.

[lsfreak]

I am not quite sure if canides are not a bit better in this, but yes, it's good to be human. And besides, we own the canides anyway. And do it for a long, long time. Much for their and our rejoicing.
This is an actual point: Domestication and as such an enforced symbiosis is basically the use of other creatures as a tool.

Canids tend to be a lot faster than us, but we can go longer. Wolves, wild dogs, and spotted hyenas (not canids, but whatever) tend to make kills after a relatively short chase (from what I remember, say 5 miles or half an hour) due to their faster speed. Modern endurance hunters can go significantly longer than that both in terms of time and distance (of course that's modern hunters, out ancestors didn't have water bottles).

[hamishspence]

Waterskins? A little butchery, and you have something to carry water in.

[Ravens_cry]

Waterskins? A little butchery, and you have something to carry water in.
Yeah, it's obvious, but first you have to invent butchery, realizing that that skin you clawed off of that antelope to get at the good stuff might be useful for something.

[Satyr]

While it might not be the most aesthetic choice, one can make a good water carriers out of the bladders of most larger animals.

And it is usually agreed (as far as I know) that foraging fruits and vegetables was probably more important than hunting in paleolithic times and thus the most important discovery of that time was ...drums... the sack.

[Oslecamo]

This might be a very anthropomorphic perspective, (because we use tools and we are awesome, tool use is awesome, and thus means you are extra smart), but yes, there is a strong hint that manual dexterity has a great impact on overall intelligence (just compare octopi with snails), but it is not as much an ability in itself, but a proof for the actual ability: a complex problem solution mechanism and adaptation, combined with the transfer of of something you already know to something completely new (this is basically what you need to build any tool that is more advanced than a club).

Altough that allows to build stuff, trial and error works suprisingly well. A lot of our discoveries are made randomly. You just need to be smart enough to recognize something usefull when you see it, then it's repetition.

And that's why we strive as a species. Only a few of us are actualy super creative dudes able to make new usefull stuff, but pretty much every human can then be teached to mass produce said usefull stuff.

Said usefull stuff is then passed down generations and improved. Whitout it being passed trough copying your elder's toys we would be still hunting antelopes with rocks and sticks in the Savannha



Another adaptation is swimming. Which allowed us to ford rivers and lakes as we migrated across the landscape in a world before tools.


Not really swimming, but "not scared the hell out of water". Primates and other mammals have completely tied cuts with water. They only aproach to drink it.

We humies are willing to go back to the water, but we're horribly slow on it and drown easily.

Wich is more than enough when you're facing something like a lion wich isn't willing to jump in the water.

But really isn't enough when you're facing an actual aquatic predator like a croc.

[Volthawk]

That's nothing. We can leap tall buildings in a single bound, have enormous genitalia for our size, possess dexterous hands, can see through walls, can fly around the planet so fast we travel back in time, become an analogue for perfection in every way while wearing a silly pair of tights, and invent thousands and thousands of fictional beings and worlds that exist only to tell us these things over and over until you'd think our spines would be sore from fellating ourselves, although that's probably because they're not properly and fully adapted to bipedalism which doesn't matter because we are SO AWESOME.


Fruit flies are better in that respect.
>.>
<.<
Anyways....

[PhoenixRivers]

Wich is more than enough when you're facing something like a lion wich isn't willing to jump in the water.

But really isn't enough when you're facing an actual aquatic predator like a croc.
Just to note: There are a few prides of lions that aren't afraid of water. One actually uses it to drown large game.

Lions tend to be one trick ponies, though the trick differs. Some prides have specialized in hunting elephants, whereas most lions won't go near one.

[Satyr]

That's true for most animal populations in fact. There are some groups who know a neat trick and other who don't, but no group seem to know all the tricks.

BTW, there are many mammals who have no fear of water. Tigers swim a lot (especially for cats), most dogs just love to jump in any stinking pool they can find. And let's not forget all those amphibic living oes like otters, beavers and the like.

Other primates seem to not like water, but mostly because they don't have the same buoyancy as humans. Chimps literally cannot swim; their body's muscle density is too high, so they don't float (or just don't float as well). There was a popular theory, that modern men adapted to their current form - few hair, nostrils pointing down - because they developed in coastal areas or near rivers and coud gain a neat extra source of nutrition from the water.I think it is challenged nowadays, if not outright debuked, but the fact remains, humans can swim pretty well for lanflubbing animals.

[Serpentine]

Something only we humies can do.This has been said so many times about so many things it's pretty much lost all meaning. I'm willing to bet it's only a matter of time before this one's debunked, too.
The most convincing "X seperates man from animals!" I've seen so far is religion and care of our dead, but the fact that elephants have been shown to mourn their dead might indicate that this one isn't entirely true, either. Even the development of culture, abstract thought, empathy and a sense of fairness has been demonstrated in various animals.
Not really swimming, but "not scared the hell out of water". Primates and other mammals have completely tied cuts with water. They only aproach to drink it.As pointed out, there are many, many mammals that are totally okay with water. Moreover, these guys don't look particularly "scared the hell out of water":
http://images.quickblogcast.com/2/1/1/8/3/147376-138112/bonobo_water_splashing_george_zaharoff.jpg
http://lh5.ggpht.com/_9ltnjAAhFPs/SWQMOHh8PiI/AAAAAAAAAp0/3SP5eV0iCAU/s288/Chimp%20in%20Water.jpg
http://www.arkive.org/media/75/7583E92E-4A17-4B35-9361-89AF98249999/Presentation.Large/photo.jpg

[hamishspence]

The bigger myth is that tyrannosaurus and triceratops actively engaged in epic duels to the death.

In the pop culture books I read, it was generally a single short clash, rather than an epic duel (generally ending with the T. rex retreating with a wound.)

Given that a lot of theropod skeletons have lots of healed minor injuries (including broken bones) this would suggest that injury wasn't always a sentence of death.

[Drakyn]

In the pop culture books I read, it was generally a single short clash, rather than an epic duel (generally ending with the T. rex retreating with a wound.)

Given that a lot of theropod skeletons have lots of healed minor injuries (including broken bones) this would suggest that injury wasn't always a sentence of death.

In the case of Big Al (http://en.wikipedia.org/wiki/Allosaurus#.22Big_Al.22), it was both. He was probably the sort of person you leave in an empty room, you come back in five minutes, they've snapped their clavicle over their kneecap or something.

[Oslecamo]

This has been said so many times about so many things it's pretty much lost all meaning. I'm willing to bet it's only a matter of time before this one's debunked, too.

Good luck with that. There's a reason why it's the most recent definition of advanced intellegence. It still hasn't been countered.

As for a "matter of time", let me point you to the fact that tools are something that lasts after an animal's death, at the contrary of behavior. If animals were building sophisticated tools from other tools, we would be bound to have found something by now.

So yeah, my bet's is on this one staying true.

Also, are you stating that modern Physics "lost all meaning" because it resulted from the debunking and evolution of several theories over the last 500 years?



The most convincing "X seperates man from animals!" I've seen so far is religion and care of our dead, but the fact that elephants have been shown to mourn their dead might indicate that this one isn't entirely true, either.

But we haven't seen other animals building tools from tools. Humans still hold exclusivity in that department (and for the point dolphins and several of other herbivores do mourn their dead).


As pointed out, there are many, many mammals that are totally okay with water.

And when did I say all mammals are scared of water? Most of them are better swimmers than us and everything.



Moreover, these guys don't look particularly "scared the hell out of water":
http://images.quickblogcast.com/2/1/1/8/3/147376-138112/bonobo_water_splashing_george_zaharoff.jpg
http://lh5.ggpht.com/_9ltnjAAhFPs/SWQMOHh8PiI/AAAAAAAAAp0/3SP5eV0iCAU/s288/Chimp%20in%20Water.jpg
http://www.arkive.org/media/75/7583E92E-4A17-4B35-9361-89AF98249999/Presentation.Large/photo.jpg

Yes, they do like swallow waters in wich they have no risk of drowning whatsoever. Try throwing a monkey into a river more than 2 meters deep and see what happens.

[Serpentine]

Good luck with that. There's a reason why it's the most recent definition of advanced intellegence. It still hasn't been countered.That was also true of the "only humans have emotions", "only humans use tools", "only humans make tools", and "only humans have abstract thought" theories. They've all been debunked, one after another. This "tools from tools" one is very recent, and it'll have to stay around and be studied a lot before I'll put much faith in it.

As for a "matter of time", let me point you to the fact that tools are something that lasts after an animal's death, at the contrary of behavior. If animals were building sophisticated tools from other tools, we would be bound to have found something by now.Not necessarily. We only recently started looking at homosexuality in animals, for example, and suddenly it's everywhere. Even thinking of animals as something more than automatons is a relativley recent development.

Also, are you stating that modern Physics "lost all meaning" because it resulted from the debunking and evolution of several theories over the last 500 years?That example would only be analogous if I had said "animal psychology has lost all meaning". Now, if you had said, "are you stating that the statement "the speed of light is a constant" because it has been debunked over the last several decades?" then you might be onto something. 'course, I kinda would, seeing as we now know that the speed of light is not constant.

But we haven't seen other animals building tools from tools. Humans still hold exclusivity in that department (and for the point dolphins and several of other herbivores do mourn their dead).Like I say above, until recently we hadn't seen animals get it on with other animals of the same sex. Now we've seen a lot of it. And frankly, even if we are "the only animals that make tools from tools", that seems like a pretty weak thing to make us thpecial...

And when did I say all mammals are scared of water? Most of them are better swimmers than us and everything.
Primates and other mammals have completely tied cuts with water. They only aproach to drink it.Perhaps I, and the others, misunderstood this passage, but it definitely seems to be implying that all other mammals are scared of water.

Yes, they do like swallow waters in wich they have no risk of drowning whatsoever. Try throwing a monkey into a river more than 2 meters deep and see what happens.That they were in the water at all discounts the aforementioned claim that "primates... have completely cut ties with water (and) only approach to drink it". Also, I'm pretty positive I've seen at least one other ape or monkey swimming. I'll see if I can find it.
edit: Yep, a google search for "monkey OR ape swimming" comes up with more than 1.5million results, most of which on the first page are indeed of a monkey or an ape swimming.

[hamishspence]

What does "building tools from tools" mean, anyway?

If what is meant is "Taking a non-useful object, and modifying it, so that it becomes a useful tool"- humans aren't unique in that. Corvids, and chimps, modify twigs so they can be used as tools- when the initial twig was not useful.

This is different from merely using existing objects as tools without modification- a lot of animals do this. Usually with stones.

The really unusual one- is creating tools which have one primary purpose- making it easier to make more tools. A saw, for example.

This is tending to drift off the original topic- which was dinosaurs- how intelligent the are, and so on.

Could there have been a tool using dinosaur, which left no trace of its tool use in the fossil record?

Quite possible- 65+ million years can destroy a lot of evidence. We're lucky to have as many fossils as we do.

And some tools and evidence of civilization- wooden tools and building materials, cloth, etc, won't fossilize easily anyway.

In practice though- there isn't much in way of evidence for unusual manual dexterity in any dinosaurs.

[Serpentine]

Huh. Turns out Darwin himself said what I've been trying to:
the difference in mind between man and the higher animals, great as it is, certainly is one of degree and not of kind

[Brother Oni]

There have been several mentions of humans as excellent endurance hunters (chasing down prey until they're too tired to run away) - I'd like to point out that this is almost solely in hot climates, due to our relatively excellent thermoregulation.

It's one of the reasons why we domesticated wolves and the like, they're some of the only animals that can keep up with us.

In more temperate climates, Mr Deer is going to out-run you and you're not going to be able to catch him.



In a much earlier point, somebody mentioned binocular vision on T-Rexes. As stated earlier, binocular vision grants depth perception, a trait only useful for hunting animals (herbivores don't need it as that foliage isn't going anywhere), thus T-Rexes probably did hunt occasionally when they couldn't find carrion to eat.

As a quick rule of thumb for determining whether an animal is prey or a predator, look at the eye placement on the skull - frontal placement indicates a predator of sorts, side placement indicates prey (they can scan more of the surrounding area so predators can't sneak up on them).

[hamishspence]

I tend to the view that it was more "never passed up a free meal" than "hunted only when they couldn't find carrion to eat"

The immediate predecessors to T. rex were Gorgosaurus and Daspletosaurus. Both were of similar size, but Gorgosaurus was gracile, Daspletosaurus robust- and the theory as to why two predators of similar size but different shape existed in the same area- was prey specialization.

With the gracile Gorgosaurus hunting hadrosaurs, and the robust Daspletosaurus hunting ceratopsians.

While one could theorize that T. rex was a scavenger while its ancestors were predators- and it retains all the predatory adaptations because it hasn't had time to lose them, this seems a bit contrived.

It makes more sense to me, that T. rex is simply a further progression of Daspletosaurus- grown a bit larger, so as to hunt prey which has also grown a bit larger.