Proto-mammals survived ancient global warming in Antarctica

Fossil-probing boffins say they have found evidence that early mammal-like creatures survived a severe episode of global warming 252 million years ago by moving to Antarctica. Most other species then living were wiped out.

The new research comes from scientists at the Field Museum in Chicago and the University of Washington. According to a statement released by the Field Museum:

Scientists are still debating what caused the end-Permian extinction, but it was likely associated with massive volcanic activity in Siberia that could have triggered global warming... A new fossil species suggests that some land animals may have survived by living in cooler climates in Antarctica.

The new species in question is Kombuisia antarctica, a curious critter classed among the anomodonts, "mammal relatives" which are now all extinct but which were the main plant-eaters in the era prior to the big die-off.

"Kombuisia antarctica, about the size of a small house cat, was considerably different from today's mammals — it likely laid eggs, didn't nurse its young and didn't have fur, and it is uncertain whether it was warm blooded," says Kenneth Angielczyk, assistant curator of paleomammology at the Field Museum.

Angielczyk and his colleagues say that Antarctica hadn't yet moved fully down to its present position at the south pole at the time of the extinction, and as a result it was somewhat warmer and not covered in ice. However it was cooler than the rest of the supercontinent Pangaea, from which today's land masses broke off, allowing K antarctica to survive there when the rest of the world became uncomfortably hot.

The scientists discovered the creature among fossils collected thirty years ago and stored at the American Museum of Natural History since then. The boffins who analysed them when they were first obtained were primarily interested in Pangaea, rather than species survival through the extinction.

The new study is to be published in the journal Naturwissenschaften today. ®