The forest found in the town of Cairo–about 40 miles south of Albany–has been dated to about 385 million years old. Which makes it around 140 million years older than the first dinosaurs on earth. It is one of the only three known fossil forests dating this period. Previously, scientists thought a fossilized forest in Gilboa, New York, was the earliest but the newly discovered one is two or three million years older and completely different.
Christopher Berry, study co-author and a paleobotanist at Cardiff University in the United Kingdom, told CNN he was a bit skeptical the first time he visited the site. He thought a modern tree might have grown into the rock and been removed. After closer inspection of the soil, researchers confirmed they were looking at the footprint of something much, much older.
The discovery provides a snapshot of one of the planet's great transitional periods, between an earth with no forests and an earth that's covered in forests, Berry said.
The team hypothesizes a catastrophic flood killed most of the trees in the forest and preserved the root system as fossils. They even found fish fossils near the largest trees. During the Devonian period, scientists say a drastic drop in CO2 levels led to a cooling of the earth, which may have caused an extinction at the end of the period. "That's sort of the opposite of what we're experiencing today, with the possibility of an extinction as well," William Stein, lead author and emeritus professor of biological sciences at Binghamton University, said. "So in that sense, history matters. If we look at the origin of these forests and their effects, and particularly the plants themselves and what they're doing, we may have an insight into processes that are going on today."