By Michael Perry
SYDNEY (Reuters) - Hundreds of human footprints dating back 20,000 years to the Ice Age have been discovered in a dry lake bed in Australia, scientists said on Thursday.
University of Melbourne archaeologist Matthew Cupper told Australian radio they were the earliest footprint fossils found in the country.
A human footprint, one of many left by adults, teenagers and children walking and or running across moist clay flats, is seen on a dry lake bed near Willandra Lakes, southwest of Sydney in this December 14, 2005 handout photo. (REUTERS/Michael Amendolia-with permission of traditional landowners)
"It's really quite a remarkable find. It's a little snapshot in time. The possibilities are endless in terms of getting a window into past aboriginal society."
They were left by adults, teenagers and children walking or and running across moist clay flats near Willandra Lakes, southwest of Sydney, the university archaeologists who made the discovery said.
The prints, ranging in size from 13 cm to 30 cm, provide an insight into the anatomy and behaviour of the people who left them, they said in an on-line report in the Journal of Human Evolution (www.sciencedirect.com).
"The size of the prints and the pace lengths in most trackways indicate tall individuals who were able to achieve high running speeds."
Some of the people appeared to be hunting, with emu and kangaroo footprints also in the area and what appeared to be spear holes in the ground, they said.
One man, estimated at two metres (six feet) tall, appeared to be sprinting at about 20 kmh.
Australia's oldest human remains are 40,000 years old and were found in Lake Mungo in Mungo National Park, where the footprints were discovered.
The on-line report said 457 footprints, "the largest collection of Pleistocene human footprints in the world", had been discovered since the first were found in 2003.
The Pleistocene period is from around 1.8 million to 10,000 years ago and includes the most recent Ice Age. The footprints were dated at between 19,000 and 23,000 years old.
"It's quite remarkable," Cupper said. "We haven't found any footprints from the Pleistocene in Australia before."
A young woman named Mary Pappin Junior from the Mutthi Mutthi aboriginal people found the first footprints in August 2003 while exploring the area with a team member from Bond University in Queensland state, Cupper said.
They were made in silty clay containing calcium carbonate that hardened like concrete as it dried. The imprints were preserved when they were covered by a layer of clay and then sand from shifting dunes.
The scientists dated the footprints through a technique known as optically stimulated luminescence of the sand.