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: .1. animal was endothermic and had a high metabolic rate2. animal was most closely related to alligators and crocodiles3. animal had evolved from birds4. species had little to no need to regulate blood pressure