Technically speaking, birds are dinosaurs

The gene pool of today's birds is larger than expected: "Urvogel" Archeopteryx was apparently not that unique

Washington. As a bird among dinosaurs, the "primeval bird" Archeopteryx was apparently by no means alone, because 150 million years ago several dinosaurs probably had a bird-like and therefore larger brain than reptiles. US researchers have now found out in comparative 3D studies of the skulls of dinosaurs and birds. They report on their results in the journal "Nature". It is therefore questionable whether the Archeopteryx was actually the first bird in the history of the earth.

Experts have been arguing for years about whether the feathered "primeval bird" was still a dinosaur or already a bird. Since its discovery in Solnhofen in Bavaria in the middle of the 19th century, the Archeopteryx has been seen time and again as the forefather of all birds. In recent years, however, especially in Asia, scientists have found more and more dinosaur remains with bird-like features such as feathers that scratched the status of the "primeval bird".

Flying needed bigger brains
In any case, the Archeopteryx was a descendant of the dinosaurs. Presumably it could already slide or flutter. From the reptiles, however, some features - such as the bone tail - had been preserved. However, flying also made higher demands on the brain, so compared to reptiles, birds have a larger brain in relation to their body size.

The examinations of the skulls now showed that some types of dinosaurs that lived at the same time as the Archeopteryx also had a brain that was fit to fly. "The Archeopteryx has always been seen as a unique transition species between feathered dinosaurs and today's birds," said Amy Balanoff of the American Museum of Natural History. "But by studying the skull volume of closely related dinosaurs, we discovered that the Archeopteryx may not have been that unique."

The study even made it clear that some non-pterosaurs actually had an even larger brain for their body size than the Archeopteryx. These included the feathered Oviraptoro dinosaurs and the bird-like Troodontidae. The gene pool from which today's birds emerged was therefore much larger than previously thought.