Monotremes and Marsupials Objectives

• Describe the difference between monotremes and marsupials.

• Name the two kinds of monotremes.

• Give three examples of marsupials.

• Explain why many marsupials are endangered or extinct.

I. Monotremes A. A monotreme is a mammal that

lays eggs. Monotremes have all the traits of mammals, including mammary glands, a diaphragm, and hair. They are also endothermic.

B. A female monotreme lays eggs with thick, leathery shells. She uses her body energy to keep the eggs warm.

C. Monotremes do not have nipples. Their young lick milk from the skin and hair around the mother’s mammary glands.

I. Monotremes

D. Echidnas: Their large claws and long snouts help them dig ants and termites out of insect nests.

E. The Platypus: The other living monotreme species is the platypus that lives in Australia.

F. Platypi are swimming mammals that feed and live in rivers and ponds. They use their webbed feet and flat tails to move through the water. Their flat, rubbery bill is used to dig for food and dig tunnels in riverbanks.

Echidna Video

II. Marsupials A. A mammal that carries and nourishes its young in a pouch is a

marsupial.

B. Like all mammals, marsupials have mammary glands, hair, and specialized teeth. They give birth to live young.

C. Marsupials development is unique because newborn marsupials continue their development in a mother’s pouch.

II. Marsupials D. The Pouch: Marsupials are born at an

early stage of development. They are born just days or weeks after fertilization.

E. Newborns drag themselves through their mother’s fur to the pouch on her belly where they continue to develop. Inside the pouch, the newborn latches onto a nipple, and starts drinking milk.

F. Young kangaroos, called joeys, stay in the mother’s pouch for several months.

II. Marsupials G. Kinds of Marsupials Familiar marsupials

include kangaroos, opossums, and koalas. Most marsupials live in and around Australia.

Wombat

Wombat Facts

Tasmanian Devil

Tasmanian Devil Facts

II. Marsupials

H. Endangered and Extinct Marsupials The number of living marsupial species is decreasing. Several species of marsupials have gone extinct in Australia, and many more species are in danger.

I. When Europeans came to Australia they brought exotic species such as rabbits, cats, and foxes. These exotic animals compete with marsupials for food or prey on marsupials.

J. Habitat destruction and hunting have also threatened marsupials.

Eastern Pygmy Possum

Possums and Opossums are different animal groups. Possums are native to Australia and opossums live in the western hemisphere.