Scientists Discover Fossil That Does Not Belong to Any Known Life Form Classification
Scientists Discover Fossil That Does Not Belong to Any Known Life Form Classification
Scientists have discovered a 400-million-year-old fossil of an organism known as Prototaxites, which does not belong to any known life form classification, as it is not a plant, an animal, or a fungus. Instead, the organism’s taxonomic placement is debated.
Scientists hypothesize that Prototaxites dominated prehistoric Earth between 420 and 375 million years ago, during the Silurian and Devonian periods. These structures resembled tree trunks and could reach up to 8 meters (26 and a quarter feet) in height and one meter (3 feet) in width.
The first Prototaxites fossil was unearthed in 1843, sparking a debate over what it actually was: a plant, giant algae, or fungi.
The new study reveals the fossil of this previously unknown life form has compounds found in plants
A 2007 study by Kevin Boyce from Stanford University initially leaned toward the possibility that Prototaxite was fungi, as after analyzing one fossil’s isotopes, they concluded this specimen did not photosynthesize like plants. Instead, these life forms absorb carbon much as fungi do.
A new study, this one led by Corentin Loron from the University of Edinburgh, focused on the smaller Prototaxites species, known as Taiti, which was discovered at the Rhynie chert fossil bed in Scotland, and offered a contrasting perspective.
400mln lat temu na Ziemi najwyższymi roślinami były grzyby Prototaxites pic.twitter.com/UEPR22XC35
— Ribald (@panciosuperstar) March 18, 2025
The research team compared the chemistry of the fossil to that of actual fungi found at the same site. This comparison revealed that Prototaxites did not contain chitin, a molecule that forms in fungal cell walls. Instead, scientists discovered lignin-like compounds in the fossil, which are typically found in plants.
The organism’s genetic lineage lacks similarities to modern life
Loron’s study also revealed that Prototaxites have three characteristics not seen in contemporary life forms. First, they discovered this organism formed large multicellular structures composed of various types of tubes. The team also found they contain biopolymers that resemble lignin.
This means that Prototaxites’ cell walls are constructed from a natural polymer similar to the tough materials that strengthen plants, rather than the chitin typically found in fungi. Additionally, the study revealed that they fed on decaying organic matter.
Crucially, early Prototaxite fossils had varied interpretations. For instance, in the 19th century, scientists considered Prototaxites as giant algae. The modern debate on the specimen’s taxonomic placement can be attributed to recent studies utilizing microscopy and geochemical analyses, which fuel the debate between plants and fungi.
The debate is not expected to slow, because scientists are still unsure about this specimen’s taxonomic placement.