Rewriting the History of Plants on Earth

By Jim Brace-Thompson

For some 90 years, paleobotanists have known about an ancient group of plants known as Noeggerathiales from 325 to 251 million years ago. But fossils of these plants were few, fragmentary, and far between. Scientists kept asking how, exactly, they are related to other plants, living and extinct.

Thanks to a find and to new research recently published in Proceedings of the National Academy of Sciences by paleobotanists Jun Wang (Nanjin Institute of Geology and Paleontology, China) and David Dilcher (Indiana University), we now know that plants belonging to the Noeggerathiales group were much more important than previously thought, even though the group went extinct with the Permian mass extinction event 251 million years ago.

Nearly 15 years ago, Wang discovered the best and most complete examples of Noeggerathiales fossils courtesy of a coal mine in Inner Mongolia. The fossils had been preserved in volcanic ash deposits dated at 298 million years old. Wang named them Paratingia whuaia.

Wang and Dilcher determined that P. whuaia, with a woody trunk and palm-like leaves, occupied a niche somewhere between ancient spore-bearing ferns and fern trees and the seed-bearing plants so common on today’s Earth. Thus, in a single stroke, Wang and Dilcher have rewritten the history of plants on Earth. Wang looks forward to still more surprising results as he continues to analyze finds from this locality.