Etched into the stone floor of an abandoned quarry in upstate New York is a tangle of webs that look almost like tentacles.

“We’re walking across this quarry floor and my eye just unconsciously picked up on an odd pattern,” geologist Chuck Ver Straeten said. “It looked like a shallow little gutter that kind of meandered back and forth a little bit while it went out mostly in one direction. And it’s like … what is that?” 

Following the trail of these gutters, Ver Straeten and his colleagues observed that eventually all paths met at a central trunk. “And it didn’t take too long before we realized, Wow! That is where a tree stood 385 million years ago!”

And it wasn’t just one tree, there was a whole preserved forest floor carved into the stone. In fact, this was one of the very first forests on the planet. It was “such an awesome, awesome, awesome thing to imagine a forest from that long ago,” Ver Straeten said.

This fossil forest represents a time when plants tipped from just finding their footing on land to exploding across the planet, changing everything in their wake — so dramatically so that they may have also triggered one of the biggest mass extinctions in the history of the Earth.

In this episode of Unexplainable, I explore the upheaval of life in the deep past.

We are on the brink of another mass extinction today, but we may not be the first living beings to overturn the planet and kill the majority of life on Earth. What can we learn from this ancient climate apocalypse?