Because thy are stretching tight muscles as a result of being in one position for a long period of time.
It Is The Babinski Reflex
They cannot sleep on their backs because their body shape and mass makes it impossible for them to lay, let alone sleep on their backs like a dog or cat can. They have a huge gut that can get easily twisted up if they roll onto their backs, and thus can only lay and sleep on their sides or chests with their feet tucked under.
they sleep on branches of tall trees or on mountain bluffs but they sit up sometimes with their heads resting under their wings on their backs
When you sleep, most people sleep on their backs. The majority of you're blood then goes behind you, so when you wake up you look pale.
Cheetahs sleep for about 12-13 hours wow that's alot of sleep.!
Just like humans, because they will fall.
To scare away predators wolves will arch their backs and growl. If that does not work, they'll put up a fight, mostly using their teeth and speed to chase them down. also they have camoflage
Dogs do always go to sleep because they do so much running and other things so they go to sleep to wake up and feel nice and rested reddy for a new day running.
dogs can sleep in your bed as long as you want it to but make sure it's clean, also depending on which breed you have if it drulls a lot then i would'ent reccommend it, or you could ring up and ask you vet.
The arch is in Mo. not Il.
at the arch
Well, I am guessing that they sleep curled up because it keeps them warm. Also, it may be very comfortable sleeping like that. Imagine cats sleeping all spread apart! Not very comforting to me!