Very Small, Very Far Away: Signs Of Microbial Life On Mars?
A scientist looking at patterns in an ancient lake on Mars says she's found signs that ancient microbial life could have existed on the planet.By Sebastian Martinez | January 8, 2015
Microbial mats, like this one, might be key to finding concrete signs of life on Mars.
The mats are big groups of microscopic organisms, like bacteria, which usually develop in aquatic or semi-aquatic environments. (Video via Smithsonian Institution)
They're some of the oldest living things we have fossils of. One found in Western Australia dates back some 3.5 billion years: just a billion years younger than the Earth itself. (Video via Old Dominion University)