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What Makes a Mammal? Mammary Glands

What's so great about milk?

It's rich in nutrients, full of antibodies, and easy to digest. On top of that, it's portable and convenient. Nursing mammals have milk ready for their babies round-the-clock. But not all mammal milk is the same.

African Elephant

Milk for this mammal is very low in protein.


Baby chimpanzees receive milk that is very low in fat and protein.

European Brown Hare

Milk for this mammal is high in sugar and protein.

Hooded Seal

Milk for this mammal has the highest percentage of fat of any mammal—61%!

Red-Necked Wallaby

Two kinds of milk are produced for different ages.

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