It may be hard to believe, but forests once sprawled across Antarctica. University of Wisconsin-Milwaukee (UWM) geologists recently climbed the slopes of McIntyre Promontory in the Transantarctic Mountains to uncover fossil fragments from 13 trees that greened Antarctica more than 260 million years ago – before the first dinosaurs roamed the planet.
Geologists Erik Gulbranson and John Isbell ventured to Antarctica for evidence of the trees that once flourished there. The fossils they discovered are over 260 million years old, meaning forests thrived around the close of the Permian Period, which ended in Earth’s largest mass extinction. The planet shifted from icehouse to greenhouse conditions, according to UWM, and over 90 percent of species vanished – including Antarctic trees.
Gulbranson thinks the Antarctic forest trees were a hearty species, and is working to figure out why they went extinct. He said in a statement, “This forest is a glimpse of life before the extinction, which can help us understand what caused the event.”
In the last days of the Permian Period, Antarctica was part of Gondwana, and was warmer and more humid than today. Gulbranson said the Antarctic forests would have been different from what we think of when we hear the word forest today. Permian Era forests contained a “potentially low diversity assemblage of different plant types with specific functions that affected how the entire forest responded to environmental change,” according to UWM. The university described the forests as robust – but even they were no match for high carbon dioxide concentrations during the mass extinction.
Gulbranson is returning to Antarctica, and aims to discern how the forests reacted to increasing amounts of carbon dioxide, saying, “The geologic record shows us the beginning, middle, and end of climate change events. With further study, we can better understand how greenhouse gases and climate change affect life on Earth.”
http://ift.tt/2A4vJaT Source: https://inhabitat.com