Sixty-six million years ago, an asteroid slammed into what is today the Yucatan peninsula of Mexico. The impact was so forceful that it kicked a tremendous amount of debris out of the atmosphere, which then rained back down, blanketing the Earth's surface with a layer of dust.
All that debris re-entering the atmosphere created a pulse of heat so strong that it set the world on fire.
As @laelaps describes so vividly in her book, The Last Days of the Dinosaurs, this heat -- which only lasted a few hours--was lethal to most animals on the Earth's surface.
Most of those that survived were the ones that could hide in burrows or in the wet protection of lakes, swamps, or the oceans. And then they had to contend with a blasted, charred landscape where little plant life remained except as seeds or roots in the soil.
The survivors weren't out of the proverbial woods yet. The ash of these global fires, and the dust from the impact, then severely cooled the planet in an "impact winter" that lasted for years. Most plants lacked the light they needed to thrive. Food was scarce.
The recovery of life in the aftermath of this mass extinction is one of the greatest stories of resilience in Earth's history.
And we owe it, in part, to the humble fern.
The fossil record is like a book read in the rocks. Some pages (rock layers) are really detailed, with lots of information. Others are missing -- sometimes entire chapters. Sometimes, individual pages are really thick, and the words are blurry -- you can only make out fragments.
The K-Pg impact is not one of those blurry, thick layers where the geologic timeline is muddy.
@JacquelynGill This reminds me of Rachel Carson’s quote from The Sea Around Us:
“The sediments are a sort of epic poem of the earth. When we are wise enough, perhaps we can read in them all of past history. For all is written here. In the nature of the materials that compose them and in the arrangement of their successive layers the sediments reflect all that has happened in the waters above them and on the surrounding lands.”
Good thread, btw.
Jacquelyn Gill
Mark