Final answer:
Bats and hummingbirds are endotherms and homeotherms, as they maintain a constant body temperature through internal heat generation and insulation methods like feathers and hair.
Step-by-step explanation:
Bats and hummingbirds are examples of endotherms that are also homeotherms. These animals maintain a constant body temperature despite environmental changes thanks to their endothermic metabolism, which generates heat internally. Specifically, hummingbirds have a high metabolic rate to support their energy-intensive flight patterns, such as hovering, and both bats and birds utilize features like feathers and hair to insulate and keep body heat. Unlike endotherms, ectotherms rely on external sources to regulate their body temperature, and unlike poikilotherms, their body temperature doesn't vary widely.