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Evidence Of The Oldest Life On Land

courtesy of Gregory Retallack

Diskagma buttonii.

That’s the name of what could be a game-changer in scientific understanding of life on Earth. Diskagma buttonii is a fossil discovered by University of Oregon geology professor Gregory Retallack. The fossils may show that life on land existed 2.2 billion years ago. Earlier estimates say life on land appeared 500 million years ago. 

Retallack discovered the fossils by happenstance — literally on the side of the road in South Africa. He is a soil scientist and was studying an area where the construction of a road uncovered layers of soil buried deep in the earth. He said he wasn’t sure what he had exactly discovered, but recognized that it could indicate a “relatively heretical” possibility. But after years of testing and investigation, he proposed his theory.

We’ll hear about the world Diskagma buttonii lived in, how they wound up in on a South African roadside, and what they could mean for our understanding of the evolution of life on Earth.

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