Mammal
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Mammal is the highest-lever animal. They appear in land, sky, underwater, tree and hole. And now the figure of mammals that exist in the world are about 5000 species.
According to their reproduce, we can categorize them into three kinds of species :
(a) Egg-laying mammal
(b) Pouch-bearing mammal
(c) Placental mammal
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Egg-laying mammal
Lays egg and after the baby comes out the egg, mother feeds them milk. Nowadays there are just two species of egg-laying mammal.
- Platypus
- Spiny Anteater
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Pouch-bearing mammalsBelong to viviparity, but it never have placenta. The mother give birth to the embryo when it is not growing completely. After the embryo is fertilized mother put it into a pouch and feed it with milk. Example :
- Koala
- Kangaroo
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Placental mammalsHave viviparity. So before embryo is fertilized, it is growing completely in mother
��s body. Placental mammal got many kind of subspecies.- Tiger
- Lion
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