Rock & Gem
The Oldest Land Ecosystem on Earth (and Mars?) Revealed
It is 3.2 billion years old, it lies beneath the Barberton Makhonjwa Mountains of South
Africa, and it purportedly holds the rst evidence of a land-based ecosystem on Earth. Welcome to the
Moodies Group of rock formations. These formations record what some have described as slimy, sun-soaked shallows on land.
Per an article in the journal Science, the Moodies Group may preserve some of “Earth’s rst microbial producers of oxygen” in a land-based ecosystem. Other spots with evidence of fossilized life have been discovered within marine deposits in places like South Africa, Greenland and Australia, but this is the rst conrmed terrestrial deposit.
Christoph Heubeck (Friedrich Schiller University of Jena) has led the Barberton Archaean Surface Environments project, which has been drilling and retrieving core samples nearly 660 feet beneath Earth. ese samples seem to reveal ancestral cyanobacteria that, later in Earth’s history, would ood our planet with life-sustaining oxygen. e samples and analyses, if conrmed, may also prove helpful as NASA’s Perseverance rover on Mars drills into rocks of similar age on our sister planet. If and when such Martian cores return to Earth, how might they compare?