MICROANATOMY

Detailed explanation-1: -The mammal body has hair-covered bodies, while birds have feather-covered bodies.

Detailed explanation-2: -The definition of a bird requires feathers, a toothless beak, wings (usually allowing for flight), and the ability to lay hard-shelled eggs. Meanwhile, mammals have hair, give birth to live young, and the females produce milk from mammary glands-the structures for which the class is named.

Detailed explanation-3: -One of the main characteristics that distinguish mammals from birds, and other animals, is that mammals have hair or fur, and birds have feathers. Mammals evolved from the synapsids (such as the finback, Dimetrodon) between 320 and 315 million years ago, while birds evolved from theropod dinosaurs (like T.