Trees and forests as we know them will have appeared on Earth much earlier than previously thought, a team of researchers led by Binghamton University, New York, concluded.
Studying fossil soils in the Catskill area, near the city of Cairo, New York, the team discovered an extensive 385 million-year-old tree root system that existed during the Devonian Period.
Although seeded plants did not appear until ten million years later, these preserved root systems show that there were already trees like the ones that exist today.
The discovery was published, this Thursday, in Current Biology magazine and becomes the first proof that the transition to modern forests on Earth began earlier than originally thought.
"The Devonian period represents a time when the first forest appeared on planet Earth," said lead author of the now published research, William Stein, Emeritus Professor of Biological Sciences at Binghamton University.
Stein added that the effects were of a “first magnitude” in terms of changes in ecosystems, affecting what happened on Earth's surface and oceans, the concentration of carbon dioxide in the atmosphere and the global climate. A lot of dramatic changes happened at that time as a result of these original forests, so basically the world wasn't the same again. ”
The team had already worked in the Catskill region in 2012, discovering what they called “footprint clues” of the Gilboa fossil forest, long considered the oldest forest on Earth. The discovery now revealed, a 40-minute drive from the original site, shows an even older and very different forest.
It also shows three unique root systems, leading researchers to suggest that, as today, the forests of the Devonian Period were also heterogeneous, with different trees occupying different spaces depending on local conditions.
Researchers have identified a rooting system that they believe belongs to a species of palm tree and another tree of the genus Archaeopteris, which shares various characteristics of seed trees, although it probably released spores rather than seeds. It was also found a third root system that would have belonged to a tree from the Carboniferous period.