| Crocodiles are cold-blooded creatures, and they keep their temperature constant by basking in the sun and staying in the water at night. |
| For example, one might think that skeletal growth rates would be higher for an endothermic animal than for an ectothermic, or cold-blooded, one. |
| While most mammals and birds show signs of REM sleep, reptiles and other cold-blooded animals do not. |
| Still, bears are warm-blooded mammals and thus are more similar to humans than are cold-blooded reptiles like the alligators. |
| But because many species are cold-blooded, some sharks eat only about 2 percent of their body weight each day. |
| Large rocks or a stone wall make great basking spots for these cold-blooded insects. |
