docum on Instagram: "Here's what they're not telling you about kangaroo reproduction. What you're witnessing inside this kangaroo's pouch is a marvel of evolution. Unlike placental mammals, marsupials give birth to incredibly altricial, or underdeveloped, young. Born barely bigger than a jellybean, these tiny joeys, like the one seen here, must make an arduous climb from the birth canal, across the mother's fur, and into the safety of the pouch. Once inside, they latch onto one of four nipples,

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