sábado, 10 de enero de 2015

Rock Art Draws Scientists to Ancient Lakes


Some of the purported “swimmers” in the Cave of the Swimmers, Egypt. Credit: NASA Photo/Chris McKay

Life imitates art. And sometimes science does the same.

Seven thousand year-old rock paintings in the Sahara desert have, somewhat serendipitously, helped uncover evidence of ancient lake beds.

Researchers discovered the mineral remnants of the lake while studying a region well-known for its rock art. The most famous example is the Cave of the Swimmers, which provided a setting in the movie “The English Patient.” The drawings in the cave depict humans that appear to be swimming, floating and diving. And yet this area in southwestern Egypt is one of the driest in the world.

The generally-accepted explanation is that the climate was much wetter in the past, supporting not only the possibility of a swimming hole, but also abundant animal life, such as cows, giraffes and ostriches, which were also drawn or carved into the region’s rocks.

Scientists have previously found support for this local change in climate in ancient lake beds and other geologic data, but most of these lakes pre-date the rock art by many thousands of years. Until now, no one had identified any evidence of a relatively recent, semi-permanent lake that could have served as a swimming hole for the local rock artists.

“Indeed, we found that there were lakes not far from the Cave of the Swimmers,” says Chris McKay from the NASA Ames Research Center. [...] astrobio.net / Link 2