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KANGAROO EMBRYO


Kangaroo reproduction is similar to that of opossums. The egg (still contained in the evolutionary remnant of a shell, a few micrometres thick, and with only a small quantity of yolk within it) descends from the ovary into the uterus. There it is fertilised and quickly develops into a neonate. Even in the largest kangaroo (the red kangaroo) the neonate emerges after only 33 days. Usually only one young is born at a time. It is blind, hairless and only a few centimetres long; its hind legs are mere stumps; it instead uses its more developed forelegs to climb its way through the thick fur on its mother's abdomen into the pouch, which takes about three to five minutes. Once in the pouch, it fastens onto one of the two teats and starts to feed. Almost immediately, the mother's sexual cycle starts again. Another egg descends into the uterus and she becomes sexually receptive.