Artificial Uterus Could Save Grey Nurse Shark From Extinction

From Scientific American:

Plenty of species have been observed eating their own young. Still other species see their young competing for resources, so only the strongest survive. But the grey nurse shark (Carcharias taurus) takes it a step further: its young have a tendency to eat each other, in utero. You read that right. As grisly as it may seem, this reproductive system worked just fine for the grey nurse for millions of years. Until, that is, the rise of modern fishing techniques. Now, grey nurse sharks are dying faster than they can breed, the victims of drift nets and other commercial by-catch. In Australia, scientists estimate there are just 500 to 1,000 grey nurse sharks left, down from several thousand in the 1980s. But Nick Otway of the New South Wales Department of Primary Industries has an idea to boost that population. For the last three years, he's researched building an artificial womb that would keep grey nurse pups from eating each other. Here's how it works in nature: A pregnant grey nurse shark can carry up to 40 embryos in each of its two wombs. When they get large enough, they turn on each other, eating their womb-mates until only one pup is left in each uterus. Under normal conditions, this would create a stable shark population that rarely shrinks or grows.

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