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Native to one area or continent only.
Subclass of mammals which give birth to well-developed young. Humans are part of this subclass.
A subclass of mammals which give birth to undeveloped young, which are attached to their mother's teat. The teats are generally located in a pouch.
A subclass of mammals which includes the Platypus and Echidnas. They are the only mammals that lay eggs.
The ancient southern supercontinent that included Australia, New Guinea, South America, Africa, India and Antarctica.
Approximately 2 million - 10,000 years ago.
Approximately 5 - 2 million years ago.