
This is the only known instance of a person getting bitten by an unborn animal. Sand tiger sharks are well known for the hostile environment during development. Shark courting can involve a lot of vicious biting, so the female doesn’t resist too much when a male is looking for a mate. Instead, the real evolutionary battle of who has the best genes to be passed on happens during development.
The mother shark has up to 12 different pups in a litter, with the possibility of multiple fathers. However, she will only give birth to one. During development, the shark pups cannibalize their brothers and sisters until only the strongest one is left. The fathers whose babies were eaten not only miss out on getting to pass along their genes, but they also provided food for the offspring of the competition as well!
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