Animals can be described according to whether they generate their own body heat (endothermic) or gain most of their body heat from external sources (ectothermic). They can also be described according to whether they maintain a relatively constant body temperature (homeothermic) or allow their body temperature to fluctuate with the environment (poikilothermic). Which of the following animals is a homeothermic endotherm?
1) Walrus
2) Eagle
3) Coyote
4) Arctic shrimp
5) Salamander
6) Freshwater catfish
7) Butterfly