Few birds survived the asteroid impact that wiped out dinosaurs. A recent study has revealed that tree-dwelling birds were unable to survive the mass extinction event 65 million years ago that wiped out the dinosaurs. The experts found that the Chicxulub asteroid strike destroyed forests worldwide, completely eliminating the natural habitats of tree-dwelling birds species.
Birds with stronger legs equipped to live on the ground, comparable to modern-day ostriches, were the only avian species to survive. When mature forests returned, which could have taken thousands of years, birds diversified back into the trees.
Study lead author Daniel Field is a vertebrate paleontologist at the University of Bath.
“We drew on a variety of approaches to stitch this story together,” said Field. “We concluded that the devastation of forests in the aftermath of the asteroid impact explains why tree-dwelling birds failed to survive across this extinction event.”
“The ancestors of modern tree-dwelling birds did not move into the trees until forests had recovered from the extinction-causing asteroid.”
The research team analyzed plant fossil records to establish that forests disappeared after the impact of the asteroid. Immediately after the asteroid collided with the Earth, the fossil record showed the charcoal remains of trees, and then, tons of spores from just two species of fern.
Study co-author Antoine Bercovici is a paleobotanist at the Smithsonian National Museum of Natural History.
“This fern spike represents evidence of ‘disaster flora,’ where pioneer species are rapidly recolonizing open ground, such as seen today when ferns recolonize lava flows in Hawaii or landslides after volcanic eruptions,” Bercovici told National Geographic.
The researchers also concluded that the common ancestor to all of today’s birds lived on the ground. While there were many tree-dwelling dwelling bird species that lived alongside dinosaurs, they did not survive to have genetic ties to modern-day birds.
“Today, birds are the most diverse and globally widespread group of terrestrial vertebrate animals – there are nearly 11,000 living species,” said Dr. Fields
“Only a handful of ancestral bird lineages succeeded in surviving the K-Pg mass extinction event 66 million years ago, and all of today’s amazing living bird diversity can be traced to these ancient survivors.”
The researchers will continue analyzing the fossil record to accurately establish when the Earth’s forests recovered and to explore the diversification of birds that followed.
The research is published in the journal Current Biology.
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By Chrissy Sexton, Earth.com Staff Writer