What are the types of mammals?

Answer 1

There are three types of mammals existent in the world. Arranged from most primitive to most advanced these are:

• Monotremes (represented by the Platypus and Echidna): These are egg laying mammals
• Marsupials (represented by a possums, kangaroos and koala bears etc.): Bear live young but the major part of the pre-emergence growth is carried out in a pouch in the female's body
• Placental (Represented by all other mammals from shrews to blue whales including mankind): The entire gestation period is carried out inside the mothers body in a womb

These three types are diversified to occupy almost every ecological niche in the world.

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Mammals can be split into two subclasses, the prototheria, which includes the egg layers such as the platypus, and the theria, which includes all the placentals mammals and live-bearing marsupials.

Most mammals belong to the placental group. This can be split into 6 other groups known as orders. The orders are:

Carnivora - dogs, cats, weasels, bears, seals, and their relatives.

Rodentia - mice, rats, squirrels and other small, gnawing mammals.

Chiroptera - bats.

Soricmorpha - shrews, moles and solenodons

Cetartiodactyla - the even-toed hoofed mammals like elephants and also whales

Primates - which includes humans, chimps and gorillas.