GEOLOGY

Detailed explanation-1: -Final answer: Shark is not a mammal.

Detailed explanation-2: -Other animals with opposable thumbs include gorillas, chimpanzees, orangutans, and other variants of apes; certain frogs, koalas, pandas, possums and opossums, and many birds have an opposable digit of some sort. Many dinosaurs had opposable digits as well. Granted, most of these are primates, as are we.

Detailed explanation-3: -As a result, chimps and orangutans do not have opposable thumbs as we do. Gorillas also appear to have inherited our more primitive hand structure.

Detailed explanation-4: -lemurs and lorises have an opposable thumb. Primates are not alone in having grasping feet, but as these occur in many other arboreal mammals (e.g., squirrels and opossums), and as most present-day primates are arboreal, this characteristic suggests that they evolved from an ancestor that was arboreal.