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Morithias
2010-10-01, 11:32 AM
From what I've looked up, the average scorpion is approx 2.5 inches long, and weighs 60 grams. Using the 2x height, and 8x weight, rule. That means a human sized creature with the same body build (antro), if it was approx 6 feet, would weight almost 2 tonnes.

2.25 * 2^5 = 72
60 * 8^5 = 1.9 * 10^6

bokodasu
2010-10-01, 11:57 AM
And that's why you can't have 6' scorpions in real life.

Morithias
2010-10-01, 12:11 PM
And that's why you can't have 6' scorpions in real life.

But it is correct right? I guess my Trakeena expy is going to be one heavy lady.

Keld Denar
2010-10-01, 12:13 PM
I believe the more correct term in this case is "big exoskeleton-ed". :smallcool:

Morithias
2010-10-01, 12:15 PM
I believe the more correct term in this case is "big exoskeleton-ed". :smallcool:

Although it is going to be fun when I kill someone by sitting on them. XD

warmachine
2010-10-01, 05:36 PM
The maths is correct, it's just unnecessarily difficult. It's easier to say the multiplier to find the new length is cubed to find the new weight. That is, the multiplier for height is 72/2.25 = 32, making the multiplier for weight 32^3 = 32,768.

Though if we're going to use real world physics in magical fantasy, other aspects should be considered. The ability to support your own weight is proportional to muscle cross section, which scales to the square of dimension multiplier whereas weight scales to its cube. Otherwise known as the square-cube law. As the scorpion grows larger, it becomes less able to support its own weight. This explains why elephants have thick legs. A scorpion may have to weaken its heavy armour. Which is good, otherwise its armour thickens by a factor of 32.

Just to kill more catgirls. Oxygen intake is proportional to lung surface area, which scales to the square whereas oxygen demand, in proportion to mass, scales to the cube. As the scorpion grows, it becomes shorter of 'breath'. The respiratory system of insects and arachnids is known to be weak compared to us mammals, which is why you don't get six foot insects or scorpions.

Another consequence of the square-cube law is heat loss. Larger creatures can retain heat better and don't need to eat so much. A larger scorpion may have to move out of the desert into temperate climates.

So, the six foot scorpion has paper thin armour, lives in temperate climates and suffocates on creation because its respiratory system is rubbish. Screw it, it's magic!

Zeofar
2010-10-01, 05:54 PM
Alternatively, oxygen levels are as high as that of the Carboniferous period, which allows for giant insects of some types, or at least respiratory system that doesn't totally dominate them. Plus, you can explain Psionics, Magic, and Epic abilities as being unlocked by higher oxygen levels in all stages of life. And now you have just another one of the changes the Dungeons and Dragons gods made to the natural environment to make it awesome.

Yuki Akuma
2010-10-01, 06:59 PM
Alternatively, give the giant scorpion lungs. Nothing says it has to be exactly the same as a scorpion, just scaled up.

Starbuck_II
2010-10-01, 07:05 PM
Though if we're going to use real world physics in magical fantasy, other aspects should be considered. The ability to support your own weight is proportional to muscle cross section, which scales to the square of dimension multiplier whereas weight scales to its cube. Otherwise known as the square-cube law. As the scorpion grows larger, it becomes less able to support its own weight. This explains why elephants have thick legs. A scorpion may have to weaken its heavy armour. Which is good, otherwise its armour thickens by a factor of 32.

So, the six foot scorpion has paper thin armour, lives in temperate climates and suffocates on creation because its respiratory system is rubbish. Screw it, it's magic!

Incorrect.
Mithral is stronger than steel yet lighter.
Weight has nothing to do with strength of a material.

Morithias
2010-10-01, 09:28 PM
Alternatively, give the giant scorpion lungs. Nothing says it has to be exactly the same as a scorpion, just scaled up.

Well she is antro, but because she keeps the natural armor, poison and so on, I'm assuming her basic biology is still more scorpion than human.

Grytorm
2010-10-01, 10:58 PM
Weight has nothing to do with strength of a material.

Warmachine said nothing about the relationship of weight to the strength of materials.

warmachine
2010-10-02, 04:51 AM
Incorrect.
Mithral is stronger than steel yet lighter.
Weight has nothing to do with strength of a material.
The comparison of large and small scorpions assumes the same shape, proportions and materials. The fact that different materials have different strength to weight ratios is completely irrelevant.


As we're playing god with animal designs, giving giant scorpions lungs solves respiratory problem but is incompatible with existing, rigid, exo-skeleton design. The lung mechanism depends on expanding and contracting chest cavities. It needs overlapping armour plates or it exposes gaps as it breathes. The latter could be good for gaming reasons: "I aim my attack at a gap in its armour as it breathes in."