Like humans, female kangaroos usually give birth to one joey, or baby kangaroo, at a time. Unlike a human newborn, a newborn kangaroo can weigh as little as 0.03 ounces (0.85 g), or about the size of a lima bean. After birth, a joey uses its well-developed claws and forelimbs to crawl into its mother's pouch where it will feed, grow and continue to develop.
After several weeks, a joey may begin to venture out of its mother's pouch. Although the time a joey spends in its mother's pouch can vary by species, a joey will typically take seven months to a year before it permanently leaves the pouch.
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