Animal companion

[Doomboy911]

I'm building a ranger for an upcoming campaign where we're starting at level five.
Now I was reading this http://brilliantgameologists.com/boards/index.php?topic=4621.0 and found the dire bat which I need to be three levels higher where a few questions come to mind.
1. What happens if an animal companion dies?
2.Could I take an animal companion now and when I hit eight trade it out for the dire bat?
3. I couldn't find the book that says the dire bat can be used as a mount so if anyone knows where to find it that would be great?
4. And what would you use for a mount (I want to be an archer and flying seems best)

[WarKitty]

1. You spend 24 hours to summon a new one.

2. Yes.

3. Generally you can ride anything that is a size category larger than you are.

[Zaydos]

4. I'd use a dire bat for an aerial mount, good AC, large size, and good maneuverability.

[Doomboy911]

I think I'm going to run around on a dire rat until I hit level eight to switch to the dire bat. Do I have to be a halfling to use a dire rat as a mount?

[Flickerdart]

I think I'm going to run around on a dire rat until I hit level eight to switch to the dire bat. Do I have to be a halfling to use a dire rat as a mount?
You have to be Small to use a Medium creature as a mount.

Note that you can Ride pretty much any shape of creature, just at a -5 penalty. You can ride around on a Vargouille if you wanted, and they don't even have a body.

[Doomboy911]

Can anyone think of why I'd have to be level eight to take the bat?

[Flickerdart]

Can anyone think of why I'd have to be level eight to take the bat?
Fancy animal companions treat you as a Druid of lower level when determining their stats, and if that drops you below 1 then you can't have them, obviously. Dire Bat is 4th level or higher (level-3) but it's pretty frail until your bonus HD beef it up somewhat.