London: The oldest evidence of four-legged
vertebrate animals that lived on land about 397 million years
ago has been discovered in southeast Poland.
Scientists from University of Warsaw found oldest
footprints ever made by four-legged creatures forcing them to
reconsider a critical period in evolution: the point at which
fish crawled out of the water onto land to evolve into
reptiles, mammals and eventually humans.
"Evidence that four-legged vertebrates walked on earth
some 10 million years earlier than previously believed could
force a radical rethink of where they evolved, as well as
when," says Grzegorz Niedzwiedzki of the Department of
Palaeobiology and Evolution.
Tetrapod footprints dating back 397 million years have
been discovered in the Swietokrzyskie mountains in southern
Poland in what was, at the time they were made, a seashore.
All previous fossil evidence for these earliest known
four-limbed vertebrates has been found in river deltas and
lakes, New Scientist reported.
"The footprints are 18 million years older than the
earliest known examples of fossilised tetrapod bones. They are
roughly 15 centimetres wide, suggesting that the creatures
that left them were 2.5 metres long," Niedzwiedzki said.
PTI
First Published: Friday, January 08, 2010, 17:45