Giant, Ancient Life Form Doesn’t Fit Into Any Known Branch of Life

Hundreds of millions of years ago, mysterious life forms called Prototaxites towered toward the sky. Believed to be the first giant organisms to thrive on dry land, some species of Prototaxites grew up to 26 feet (8 meters) in height and resembled tree trunks composed of tiny interconnected tubes. Their position in the greater tree of life has been hotly debated for over a century and a half. New research suggests this is because Prototaxites don’t have a place in the tree of life as we know it—they belonged to a previously unknown branch. Researchers from the United Kingdom analyzed the fossil remains of a Prototaxites species called Prototaxites taiti and concluded that Prototaxites likely belonged to a now-extinct lineage of multicellular terrestrial eukaryotes (organisms, including all animals and plants, whose cells contain a nucleus). Their work is detailed in a study posted to the preprint server bioRxiv, and hasn’t been peer-reviewed yet. “We conducted an extensive re-examina ... Read full article.