Dinosaur Fossil May Be From Day the Dino-Killing Asteroid Struck

The asteroid that killed the dinosaurs took out 75% of species on Earth. But scientists only recently found the first fossil evidence of animals killed in the immediate aftermath. And they found it in North Dakota, nearly 2,000 miles away from the impact crater. For a field that works in millions of years, proving something happened on a particular day is quite an achievement. And it’s only one of many remarkable things about the Tanis dig site.

Glass ejected from the asteroid crater rained from the sky in the hours after impact. Scientists found many small glass beads at the dig site. Including some they believe contain pieces of the asteroid itself within them. Ejected glass is also found in the gills of fossilized fish, indicating the fish breathed them in. Scientists also found some preserved in amber.

Magnification of glass ejecta from the asteroid that killed the dinosaurs
BBC

Excavation at Tanis began in 2012. Five years passed before scientists reported any of their findings. In 2019, they published the first peer-reviewed article detailing the site’s doomsday evidence. That paper didn’t include the dinosaur fossils, which are still being unearthed.

The Tanis dig site is back in the news thanks to a BBC documentary about its many discoveries. Though all the results are not yet published and accepted by the scientific community, David Attenborough delves deeper into the findings.

Artist recreation of tsunami caused by asteroid that killed the dinosaurs
BBC

Tanis was shoreline property on that fateful day 66 million years ago. In fact, most of the central US was a shallow sea. Mega tsunamis from the impact would take about a day to make it to North Dakota. But seismic waves rocked the site within minutes. Huge earthquakes caused the sea to rise and fall. Layers of sediment and rubble at the site show clear evidence of this cycle. Fish fossils at Tanis also show the asteroid struck in spring.

Some of the scientific community are skeptical about the team’s claims. They haven’t stopped digging long enough to publish all their findings. In the meantime, the BBC special airs April 15, 2022 and later on U.S. PBS stations. And for those interested in a deep dive, The New Yorker has a great piece.