A humongous fungus among us

In the 1850s, a very large and very weird fossil was discovered in Quebec. It was named Prototaxites because it was thought to be a type of conifer (proto means 'first'; taxites from the latin taxus meaning 'yew', a type of conifer). This organism lived between 420 and 350 million years ago and has subsequently been found worldwide. At that time, land plants had been around for about 40 million years, but none stood more than a few feet high, yet here was a 20-foot monstrosity that simply dwarfed everything around it. Over the past 150+ years since its discovery, scientists have been arguing about what exactly is Protaxites. Based on more detailed observations of the organism's anatomy, the idea that it was a tree has long been abandoned. But if it wasn't a plant what was it? An exceptional large algae? An enormous lichen? How about a humongous fungus?

New research seems to have confirmed that yes, Prototaxites, was indeed a humongous fungus. By examining the carbon isotopes in the fossils and comparing them to other organisms that lived in the same area at the same time, scientists have found that chemical signature of Prototaxites most closely resembles that of fungi.

Read more:
Prehistoric mystery organism confirmed as giant fungus