After the asteroid event that struck Earth 66 million years ago, some toothless bird species may have survived due to their foraging abilities.
Birds evolved from dinosaurs approximately 160 million years ago. In fact, birds and dinosaurs coexisted for about 100 million years. Birds originated from a group of Dromaeosaur dinosaurs, also known as “running lizards,” which are a family of feathered theropod dinosaurs.
Dinosaurs once lived alongside birds but went extinct when an asteroid struck Earth. (Image: Corey Ford/Stocktrek Images).
66 million years ago, when an asteroid plummeted to Earth in the waters off present-day Mexico, it resulted in the extinction of the dinosaurs. However, some bird species continued to exist.
Scientists who specialize in avian evolution are working to understand why birds did not go extinct. They are piecing together clues from fossils and various other evidence of life on Earth in ancient times to propose several hypotheses regarding the survival of birds, although no definitive answers have yet been found.
Modern birds do not have teeth. Instead, they possess beaks that come in various shapes and sizes for feeding. During the age of dinosaurs, some bird species still had teeth, while others did not.
Following the asteroid impact, all tooth-bearing birds went extinct, but many toothless species continued to thrive. Some scientists believe that the lack of teeth was a key factor in their survival.
Fossils of ancient toothless birds indicate that they were capable of consuming more plant-based foods, particularly seeds and fruits. This means that, compared to toothy birds, they were less reliant on preying on other animals.
Ichthyornis dispar, an ancient toothy seabird that lived during the Late Cretaceous (approximately 100 million – 66 million years ago) in North America. (Image: Michael Hanson/Bhart-Anjan S. Bhullar)
Some scientists argue that the difference in diet became a significant advantage after the meteor strike. The event immediately triggered severe tsunamis and earthquakes. The immense heat from the impact caused widespread wildfires near the asteroid’s landing site. In the months that followed, a large amount of dust filled the atmosphere surrounding Earth, blocking sunlight and making it difficult for plants to grow.
For herbivorous animals, food became extremely scarce. Many species went extinct, creating challenges for predators. Numerous animal species were wiped out, and plants also struggled to receive enough sunlight, making food hard to find. However, if an animal had the ability to forage the ground for buried seeds or fruits, it could survive.
Of course, there were still other factors that allowed toothless birds to survive while their “toothed siblings” perished, including luck. Currently, this remains a mystery that has not been fully resolved.
Scientists formulate ideas or hypotheses based on existing knowledge and information. They then test these ideas by conducting experiments or gathering additional evidence. This information will either support or refute the original idea. Therefore, scientists are continually prepared to revise the narrative of how birds survived while dinosaurs went extinct as they gather more information from rocks, fossils, and ancient DNA.
