Characteristics Of Mammals

Characteristics of Mammals AS

The First Mammals • Fossil evidence indicates that about 280 million years ago, reptiles called therapsids existed. • They were about the size of mice. • This trait allowed them to look for food at night.

Making Milk • All mammals have mammary glands. • Mammary glands – in a female mammal, a gland that secretes milk. • All female mammals feed their young with this milk.

Breathing Air • All animals need oxygen to get energy from their food. • Like birds and reptiles, mammals use lungs to get oxygen from the air. • All mammals have a diaphragm, which is a large muscle that helps bring air into the lungs.

Endothermic • As oxygen helps break down a mammal’s food, energy is released. • This keeps mammals warm. • Like birds, mammals endotherms. • The ability to stay warm helps them survive in cold areas.

Hair • Mammals have hair, which helps them stay alive.

Specialized Teeth • This kind of teeth can break through almost everything.