Swamp Stomp

Volume 18, Issue 25

The extinction of the dinosaurs has been a mystery that has gripped the attention of people of all ages, from children with plastic dinosaur figurines to adults eagerly awaiting the release of the next Jurassic Park film. Recently, scientists have uncovered some clues that may help lead to obtaining the full story of how the dinosaurs went extinct, but these clues lie in a much more familiar animal than dinosaurs: birds.

Birds trace their ancestry all the way back to the dinosaurs. Many, including chickens, can trace their ancestry to a specific species of dinosaur, Archaeopteryx. Scientists have now begun to classify birds as being related to either ancient ground-dwelling or tree-dwelling species. They also discovered that the tree-dwelling birds, discovered via fossils, all became extinct due to the asteroid that killed the other dinosaurs 66 million years ago. In other words, all the birds that we see outside today, from cardinals to penguins, can be traced back to only ancient ground-dwelling birds. What does this tell us about the mass-extinction event that killed the dinosaurs? It also killed all the trees!

This deforestation is further confirmed by the species of ferns that exist today. Paleobotanist Antoine Bercovici of the Smithsonian National Museum of Natural History in Washington, DC studied the spores and pollen of ferns found in rock layers that formed in the years after the asteroid impact. He discovered that all these ferns could be traced back to only two species of ferns. This indicated that there was a mass extinction of ferns species, resulting in rapid recolonizing by the two surviving species of ferns. Bercovici says this is seen today as well “when ferns recolonize lava flows in Hawaii or landslides after volcanic eruptions.”

This new evidence may seem small, but it is another piece in the giant puzzle that is the extinction of the dinosaurs. Scientists may now know why tree-dwelling birds living in the Cretaceous period died after the asteroid hit, but they still cannot explain why certain species of ground-dwelling ancient birds also died in this event. Scientists are excited to continue piecing together the evidence that will one day, completely answer the question, “What really happened when the dinosaurs went extinct?”

Sources:

Pickrell, John. “How did Dino-Era Birds Survive the Asteroid Apocalypse?” National Geographic. National Geographic. May 24, 2018. Web. May 30, 2018.