Why do some animals curl up into a ball when they are cold?

Question

Why do some animals curl up into a ball when they are cold?

Answer 1

Do conserve body heat.  Body heat is lost through the surface area of skin exposed to the outside (air, objects, etc.).  By curling up, we animals minimize the amount of surface area exposed to the outside; so we minimize the loss of body heat.

I say "we animals" because humans should curl up if they are cold too.  In fact, covering the head is also a good idea because most (I think it's around 60%) of our heat is lost through the scalp.

Answer 2

Animals do not curl up in a ball if their cold....when an animal feals threatened they will roll up to their frightning fur(quills for porcupines) which scares of any threat or the preditor doesn't realize its their prey

if the are cold...then their fur is like a coat

Answer 3

It's a good way to keep warm.  You lose body heat through all the surfaces of your body that are exposed to the air.  By curling up tightly, you are reducing the amount of exposed surface area (for example, your tummy and your thighs are no longer exposed as much); so you don't lose heat as fast.

Answer 4

if animals curl themselves, not they feel cold ...they feel alert when they are sleeping, seems like they sleeping in a cave....to protect themselves at any time, it's nature!  If u can, provide them a pet house for their own place, let them feeling safety!