Australia's grey nurse shark could go extinct by 2050 if its populations keep dropping at current levels -- unless something unexpected saves them. Say, global warming for example.

Yes, global warming. A group of scientists this week offered up the possibility that global warming could actually keep the grey nurse shark from going extinct in Australia

It seems that the grey nurse shark is too sensitive to cold waters to migrate all the way around Australia. This has kept the continent's two populations of grey nurses separated for 100,000 years. But if climate change makes the waters around Australia warmer, the two populations could finally meet and start breeding, a shot in the arm for the critically endangered species. 

Of course, the potential to save one species isn't exactly worth the cost of global warming, and the University of Adelaide's Associate Professor Corey Bradshaw says "This is probably one of those one in a hundred examples where climate change may actually be somewhat beneficial for this particular species."

Of course, even if the shark does benefit from global warming, it will still face its existing threat: commercial fishing, which kills millions of sharks a year worldwide. 

It's also worth noting that the grey nurse shark (Carcharias taurus) exists elsewhere in the world, where it is often known by different names. The entire species is listed as "vulnerable to extinction" by the IUCN Red List. The species is worst off in Australia, where it is considered "critically endangered."

Story by John Platt. This article originally appeared in Plenty in September 2008.

Copyright Environ Press 2008