Playing hide and seek with the sun
It is night in a desert. A small lizard lies covered with sand. Only its
head sticks out. It is using the sand like a blanket to keep its body
warm during the cool night.
When the sun comes up, the lizard crawls out of the sand. It moves very
slowly because it is cold. It lies on a rock for a long time, letting
the sun warm it.
When its body is warm enough, the lizard dashes off to look for food.
Many times during the day, the lizard’s body grows too hot in the bright
sunshine. Then it crawls into the shade of a rock until its body cools
off a little.
Fringed-Toed Iguanid
Lizards and all other reptiles are cold-blooded. Then- bodies get just
as hot or cold as the air or water around them. If their bodies get
cold, reptiles can’t move well. And if their bodies get too hot,
reptiles die. So reptiles must help their bodies by playing hide and
seek with the sun. If they are cold, they lie in warm sunshine. If they
are hot, they hurry into shade. Alligators, crocodiles, and most turtles
go into cool water when they are hot.
A reptile that lives where winters are cold moves more and more slowly
as cold weather comes. The reptile curls up in the warmest hole it can
find. Its body grows cold and stiff. It cannot move at all. Only when
warm weather returns can the reptile move and start its life again.
