The Last Living Dinosaurs
by Amelia Mieko Pearson, age 12
You may not know this but birds are dinosaurs! As much as they do not look like dinosaurs, the connection between these two species does exist. In the Jurassic age, 150 years ago, the first bird was hatched from a small and feathery raptor-like dinosaur and became another branch of the dinosaur family tree.
Birds were hatched and survived for more than 80 million years. They all look different in their own ways. Some can swim, some fly, and others have unique patterns on their feathers.
Scientists group dinosaurs into two categories, avian and non-avian. The creation of these groups began after a major event that occurred 66 million years ago. That was the period when an asteroid struck, triggering a mass extinction. Over 75% of Earth’s animals disappeared. The only dinosaurs that survived were beaked birds.
Birds with beaks held a greater advantage even before the asteroid collision. Living birds today don’t have teeth but this wasn’t true long ago. Archaeopteryx, the first bird that lived 150 million years ago, had teeth and many other birds that evolved also had this trait. Overtime, birds eventually lost their teeth. It is hypothesized that this adaptation helped reduce weight for flight. Later, scientists discovered that birds with teeth could fly and this new information changed their hypothesis.
Another hypothesis for the loss of teeth may have come from a change in diet. Paleontologists have observed that some dinosaurs lost their teeth as they became more herbivorous. It is possible that birds began to use their beaks to pluck and pick foods like fruit seeds and plants. They no longer needed teeth to catch food and prey.
In addition, Abigail Tucker, an anatomist at King’s College London states, “ Changes to the skull and face as the beak became more complex may have moved developing tissues, changing how they interact in the embryo, and resulted in the loss of tooth formation.”
When the asteroid struck, these traits may have helped the birds survive. It is unlikely one trait determined life or death for these creatures but beaks could have played an important role in their survival after the strike. For years after the disaster, food was very limited. Beaked birds had varied diets that allowed them to eat foods like seeds and nuts. They could eat parts of destroyed forests, waiting decades for vegetation to re-grow. This likely helped them live longer compared to non-beaked creatures.
Over time birds evolved to be smaller with larger brains compared to their bodies. Their bigger brains could have helped them survive. Further research needs to be done to understand more about how birds survived the mass extinction. Paleontologists have fossils that date back to the Eocene 10 million years ago. They are hoping to find more information about the Paleocene period because it began after the asteroid strike. Bones from the Paleocene could uncover new information about the advantages that helped beaked birds survive.