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>"Researchers, bless their curious little hearts, have tried to implant embryos all over the bodies of mice. The single most difficult place for them to grow wa

• astrodust 9y ago
  It's the thunderdome, but not as bad as a shark uterus. They generally only give live birth to one shark because that shark has eaten all the others.
  • nasredin 9y ago
    And sharks including threshers, makos and great whites have an even odder solution: They feed their fetuses an endless stream of unfertilized eggs. 2. Sibling cannibalism Sand tiger sharks have the most ghoulish fix for hungry babies: The fetuses devour each other in-utero until there’s just one pup remaining in each of their twin wombs. This uterine bloodbath is thought to have developed because a litter of sand tiger pups usually has multiple fathers — and each dad is engaged in a proxy war for his genes to take the upper hand. The “winning” fetus gets all the nutrients from its siblings and a roomy womb to develop into an unusually big baby, over 1 meter (3 feet) long at birth. Being born large and well-developed helps these newborn predators survive in a hostile ocean.
• burfog 9y ago
  My first thought was right on top, in various layers: skin, fat, muscle, etc. Nope. They did the brain, testis, spleen, liver, and kidneys.