There have been several mass extinctions in the history of the earth. One of the largest known disasters occurred around 252 million years ago at the boundary between the Permian and the Triassic. Almost all sea-dwelling species and two thirds of all reptiles and amphibians died out. Although there were also brief declines in diversity in the plant world, they recovered in the space of a few thousand years, which meant that similar conditions to before prevailed again.
Change in flora within a millennia
Researchers from the Institute and Museum of Paleontology at the University of Zurich have now discovered another previously unknown ecological crisis on a similar scale in the Lower Triassic. The team headed by Peter A. Hochuli and Hugo Bucher revealed that another event altered the vegetation fundamentally and for longer approximately 500,000 years after the major natural disaster at the boundary between the Permian and the Triassic.
The scientists studied sediments towering over 400 meters high from North-Eastern Greenland. Carbon isotope curves suggest that the prevalent seed ferns and conifers were replaced by spore plants in the space of a few millennia. To this day, certain spore plants like ferns are still famous for their ability to survive hostile conditions better than more highly developed plants.
Catastrophic ecological upheaval changes plant world
Until now, it was assumed that the environment gradually recovered during the Lower Triassic 252.4 to 247.8 million years ago. “The drastic, simultaneous changes in flora and the composition of the carbon isotopes indicate that the actual upheaval…