Mammals are defined as animals that have hair and produce milk to feed their young. They are endothermic, which means they regulate their own body temperature. Mammals are divided into three types—marsupials, placental mammals and monotremes (egg-laying mammals).
There are only three species of egg-laying mammals or monotremes. These are the two species of echidna—long-beaked and short-beaked—and the platypus. Echidnas lay eggs in their pouch while the platypus lays its eggs in a burrow.
Marsupials, of which Australia has more than any other country, have a pouch where the young develops. The infant is born at an early stage of development and grows while nestled in the pouch.
Placental mammals form the largest mammal group. The young develop inside the mother’s uterus and are nourished through the placenta.
Mammals are found in almost all types of habitats. Some are found in the ocean (dolphins and whales), others are aerial animals like bats, and then there are those that live in trees, which are known as arboreal mammals. Many primates fall into this group, such as the orangutan. Then there are ground-living or ‘terrestrial’ mammals like elephants.
Click on the mammals below to learn more about those on display at Perth Zoo.