Ancient Earth Cores Upend Theory About Life After Dinosaur-Killing Asteroid


Lowery, a postdoctoral research and paleoceanographer at the University of Texas at Austin, says that “productivity” is the amount of energy that’s produced by an ecosystem; each member of the food chain provides and consumes energy with each other. It’s previously been theorized that the slowest recovery from the impact would be at the crater itself because of some sort of environmental control inhibited the flourishing of life, like toxic metals released by the blast.

In 2016, an international drilling mission conducted by the International Ocean Discovery Program and the Intercontinental Drilling Program pulled up a 427-foot-thick core sample using a mining drill that was welded onto the side of the Liftboat Myrtle, which wasn’t a scientific vessel and instead used for offshore oil drilling.

asteroid impact
A 2016 scientific drilling mission pulled up cores containing the first signs of life after the asteroid impact.

Within the sample, Lowery and his team discovered “survivor species” in the form of microfossils representing unicellular organisms like algae and plankton. They also found the burrowing routes that once belonged to larger organisms, like small shrimps and worms. When the asteroid hit, it’s safe to say that every organism at the site was killed and when water rushed back into it, the crater was completely sterile — but not for long.

“The life we observed must have migrated in from the nearby Gulf of Mexico,” Lowery says.

And life that lives closer to the sea floor appears to have been in the safest position to survive.

“Benthic organisms [things that lived on the seafloor] did not suffer a significant mass extinction at the K-PG boundary,” Lowery says. “The modern ocean turns over on a timescale of around 1,000 years, so it takes about that long for changes in the surface ocean to be felt in the deepest depths of the seafloor.

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“The end of the Cretaceous ocean probably had a similar overturning time, and so the environmental effects of the Chicxulub Impact must have been so brief that they only affected the surface ocean, and the deep sea didn’t feel it.”

It’s a finding that gives new life to Dr. Ian Malcolm catch-phrase.





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