joey

marsupial

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July 16, 2026

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A joey is the term for the young of most marsupials, including kangaroos, opossums, wallabies, and koalas. Marsupials are mammals that give birth to underdeveloped young after a short gestation period. These tiny newborns then make their way to the mother's pouch, called a marsupium, where they attach to a teat for nourishment and protection. The joey remains in the pouch for weeks or months, continuing its development until it is ready to be weaned and begin to care for itself.123

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kangaroo
Reproduction and development
The young kangaroo (“joey”) is born at a very immature stage, when it is only about 2 cm (1 inch) long and weighs less than a gram (0.04 ounce). Immediately after birth, it uses its already clawed and well-developed forelimbs to crawl up the mother’s body and enter…
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The young kangaroo (“joey”) is born at a very immature stage, when it is only about 2 cm (1 inch) long and weighs less than a gram (0.04 ounce). Immediately after birth, it uses its already clawed and well-developed forelimbs to crawl up the mother’s body and enter…
Read More

koala
The youngster (called a joey) first puts its head out of the pouch at about five months of age. For up to six weeks it is weaned on a soupy predigested eucalyptus called pap that is lapped directly from the mother’s anus. Pap is derived from the cecum. After…
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The youngster (called a joey) first puts its head out of the pouch at about five months of age. For up to six weeks it is weaned on a soupy predigested eucalyptus called pap that is lapped directly from the mother’s anus. Pap is derived from the cecum. After…
Read More

What Are Baby Koalas Called?
The term joey is widely used for the young of all marsupials such as kangaroos, opossums, and wallabies.
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The term joey is widely used for the young of all marsupials such as kangaroos, opossums, and wallabies.
Read More