Ken Lacovara
Appearances
Up First from NPR
The Day The Dinosaurs Died
So most of them are invertebrate fossils, clams, snails, oysters, things like that. We'll have turtles and sharks and mosasaurs and bony fish, the rare dinosaur.
Up First from NPR
The Day The Dinosaurs Died
The asteroid impact happens 1,500 miles away from here, off the Yucatan Peninsula in what is now Mexico. It blasts a crater in the Earth's crust that's about 110 miles across by 12 miles deep. So that's roughly the size of Massachusetts, say.
Up First from NPR
The Day The Dinosaurs Died
All that material is blasted up through the atmosphere, goes in the low Earth orbit. It's pulverized into maybe millimeter-sized pieces, but it still has all the mass. So you've given that mass a tremendous amount of potential gravitational energy. When that stuff comes back in, it's got to balance the energy books.
Up First from NPR
The Day The Dinosaurs Died
And the result that day, within the first hour, is global temperatures get up somewhere between toaster oven and pizza oven. So the dinosaurs that have dominated Earth's terrestrial ecosystems for 165 million years, I think are functionally extinct within an hour after that impact.
Up First from NPR
The Day The Dinosaurs Died
Well, here's what we know. I mean, all dinosaurs lived on land. Well, that day, if you can't do what little mammals did, or crocodiles, or lizards, or turtles, if you can't get into a burrow somewhere, dig underground somewhere... Well, it's between toaster oven and pizza oven. You die on the surface of the earth that day if you don't have a place to hide.
Up First from NPR
The Day The Dinosaurs Died
And it doesn't look like the dinosaurs had a place to hide. Were there a few stragglers that, you know, maybe were at the mouth of a cave or, you know, swimming at the time? Sure. But I think they were functionally extinct at that moment.
Up First from NPR
The Day The Dinosaurs Died
a bone bed that is from the exact moment of the asteroid impact. In fact, it's the only place in the world where you can see a complete death assemblage of many, many species that are victims of that event with the fallout from the asteroid.
Up First from NPR
The Day The Dinosaurs Died
but just from the ash, just from the material that falls from the sky. To date, the fossil occurrences in that layer have been very, very meager. There's some fish scales in Belgium. There's a pile of paddlefish and a dinosaur leg in North Dakota. That's about it. This site here that you're looking at has an entire collapsed ecosystem at that moment.
Up First from NPR
The Day The Dinosaurs Died
We've recovered over 100,000 fossils representing over 100 species, and they are interbedded with the fallout from that impact that happened off the coast of Mexico. So we have little glass spherules that rain down from the sky, little grains of what we call shocked quartz, and we have a spike in the level of the metal iridium, which is very, very rare in the crust of the earth, but very
Up First from NPR
The Day The Dinosaurs Died
much more abundant in asteroids. And so this makes this the best window on the planet into that pivotal, calamitous moment that wiped out the dinosaurs and really made the modern world as we know it.
Up First from NPR
The Day The Dinosaurs Died
Well, I mean, it was everywhere. We happen to have those deposits preserved here and then... We had a quarry here because of the mining operation since the first one of those that have been found.
Up First from NPR
The Day The Dinosaurs Died
Oh, there must be. You could probably go under the Lowe's and find these same deposits or the Chick-fil-A.
Up First from NPR
The Day The Dinosaurs Died
Well, I kind of do, but, you know. It's taken us 14 years to excavate only 250 square meters. And these fossils are very important to science. And so we excavate these for ourselves, but for future scientists as well.
Up First from NPR
The Day The Dinosaurs Died
And so we have to document everything very carefully, curate the material very carefully, make sure it's preserved forever so that scientists 200 years from now can study these same fossils.
Up First from NPR
The Day The Dinosaurs Died
Well, so you're looking for things that used to be alive. So you want to look for the hallmarks of life, which is pattern, form, symmetry. If you find something that looks like a random clump of dirt, it's probably a random clump of dirt, right?
Up First from NPR
The Day The Dinosaurs Died
So there are fossils right here. I see some fossils right here.
Up First from NPR
The Day The Dinosaurs Died
I do. I see fossils everywhere. So there you go. You found your first fossil.
Up First from NPR
The Day The Dinosaurs Died
This is a fossil sponge. So a sponge is a little filter feeding organism that lives on the sea floor. They draw in water and they have these little cilia, these little hairs, and they filter feed what's in the water. And you just found a 66 million year old fossil sponge. What? Yep.