Many species of animals on islands are larger than related species on the mainland. Scientists hypothesize that this phenomenon, called island gigantism, evolved in response to the scarcity of competitors and predators on islands. Reduced competition and predation allows species to exploit more resources and frees them from the need to hide in small refuges. On a trip to the Galápagos Islands, you overhear a group of tourists refer to tortoises as 'cold blooded.' Explain why this word is not accurate to describe a giant tortoise.

Video transcript

Welcome back. Let's look at our next problem. It says blank animals can naturally regulate their body temperatures while blank animals have body temperatures that reflect the outside environment. Well, let's recall from our content video that animals that naturally regulate their body temperatures are endo Therms sometimes known as warm blooded. While animals whose body temperatures reflect the outside environment. Our ecto Therms again sometimes called cold blooded. So let's look through our answer choices to find the correct answer. Well, we see choice A says cold blooded animals can actually regulate their body temperature. Well, that is not correct. Uh It's the other way around Choice B says Ecto thermic animals can actually regulate their body temperatures while endo thermic animals reflect the outside environment. Again, that's reversed as well, Choice C says warm blooded animals can actually regulate their body temperatures while cold blooded animals reflect the outside environment. So that would be correct. Finally, we have this interesting last choice which says has a kilo thermic. And home a thermic. Well, this is a little more obscure, but Akilah thermic is uh animals whose internal body temperature varies considerably, so they have to be able to tolerate wide changes in body temperature and make sure that none of their systems will be damaged by that. Whereas home a thermic we think about homeostasis, uh animals whose body temperature remains consistent and in general, you think of that as like warm blooded or endo thermic, where because they maintain their own body temperature remains consistent but some extra Therms are in this homo thermic category, if they live in environments that have relatively consistent temperatures. So even though their body temperature reflects the outside environment, if the outside environment is relatively consistent, so is their body temperature. But that obviously doesn't define correctly our choices and our question, so that's not our answer here. So again, Choice C warm blooded animals can naturally regulate their body temperatures while cold blooded animals have temperatures that reflect the outside environment. See you in the next video.