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Ancient Antarctica

Fossilised footprints have led Victoria University scientist Ken Woolfe to a re-interpretation of the history of Antarctica. Woolfe has been studying animal tracks from the Devonian period -- about 400 million years ago -- from an area of the Transantarctic mountains about the size of the North Island, west of Scott base.

Scientists have been split over whether the tracks were left by marine or land animals. The answer to the problem would determine whether that part of the continent was submerged during the Devonian period. Woolfe's research indicates that the area was covered in braided rivers, similar to some in the present day South Island, and ephemeral lakes.

"We tried some primitive modelling on the footprints and we found you just can't make them underwater -- the sand is too fluid," Woolfe says. "We also found a lot of preserved mud cracks, and in places you could see where raindrops had landed 380 million years ago; the area was probably dry most of the time. There were fossil soils, and traces of tiny streams, [suggesting] it was not covered by tidal water."

"The oldest fossil bodies are from the end of the Devonian -- about 370 million years ago -- and they are fish, but they are freshwater fish."