An anthropologist discovers the fossilized heart of an extinct animal. The evidence indicates that the organism's heart was large, was well formed, and had four chambers, with no connection between the right and left sides. A reasonable conclusion supported by these observations is that the ________.
A) animal had evolved from birds
B) animal was endothermic and had a high metabolic rate
C) animal was most closely related to alligators and crocodiles
D) animal was likely an invertebrate animal
E) species had little to no need to regulate blood pressure

Question

Quizplus · Accepted Answer

The presence of a large, well-formed heart with four chambers and no connection between the right and left sides indicates that the animal was likely endothermic and had a high metabolic rate, similar to birds and mammals. This is because such a heart structure is necessary to efficiently provide oxygenated blood to the body and regulate blood pressure in animals with high energy demands.

An Anthropologist Discovers the Fossilized Heart of an Extinct Animal