~Stages~
One of the main differences between Derpah Squirrelz and regular squirrels is that they grow from an egg. You can tell if there is a unusual tail as an egg, but not if they will have wings. They take about two weeks to hatch.

Derpah Squirrel babies are rather small, only slightly bigger than their egg. They keep their tails curled around their faces when they are sleep, and don't stand or walk much, usually eating whatever edible thing is closest to them. You can tell if they have wings by now. They take a week to grow into adults.

Adult Derpah Squirrelz are smaller and fluffier (fatter) then regular squirrels, and are therefore the perfect size for nesting in siggies. They come in a rainbow of colors, both "real" squirrel colors and unnatural, due to breeding in labs. They love to live in computers, and tend to avoid nature and the outdoors. Their favorite food are cookies, varying nuts (including acorns), and buttered popcorn.
(I "grow" the squirrels every Saturday, so expect change on Saturday or Sunday) ~Types~
There are many types and mutations when it comes to Derpy Squirrelz. Of course, new ones are always being created and discovered, and there are always special ones for special events! ;D
CommonDerp Squirrel
This squirrel is your average, run-of-the-mill type squirrel. You will most likely get one of these when you adopt.
UncommonSkinny Tailed
These squirrels have very slender tails, although not furrless.
No-tail
These have very short, stumpy tails that are not even visible from the front.
Tufty Ears
These guys have ear tufts that make their ears look slightly pointy.
RareChibi
These squirrels are even chibi-er than regular squirrels, with leetle wings.
Dragon
These tougies have horns and bat wings. They are very grumpy.
Very RareTail+Wing combos

These are squirrels that have one winged parent and one interestingly tailed parent, and are a combination of both. However, not every squirrel in a litter like this will be this way. Some will have just the tail, and some just the wings. There is only a small chance that this will happen.
Tufty No-Tail
This is the only combination involving tufty ears. They are incompatible with all other tails and wings.
OMG so Rare!Nosh Squirrel
Looks like Nomz, eh? These are rare because, well, the only way a squirrel will get a cookie is if they get it off the ground. And how many people drop their cookies? Very few. Only derp squirrels can get cookies, as they are poisonous to all other species.