Scientists have determined that Archaeopteryx, the earliest known bird, was definitely bird-brained, meaning no disrespect. Indeed, they consider the dinosaur's brain size decisive evidence that it had what it took to fly.
The new research suggests, moreover, that birds probably started flying millions of years earlier than scientists previously thought. It is just that fossils of those first flying birds — predecessors of Archaeopteryx — have never been found.
The researchers, at the Natural History Museum in London, based their findings on the first X-ray examination and reconstruction of the braincase and inner ear of a 147-million-year-old Archaeopteryx specimen. They found that in size, shape and volume, its brain was similar to that of the modern eagle or sparrow.
Measurements of the semicircular canals, the mechanism for balance inside the ear, showed that Archaeopteryx (pronounced ar-kee-OP-tur-ix) had the "neurological and structural adaptations necessary for flight," the scientists concluded.
Their research, involving an X-ray computed tomography scan, or CT, of the fossil's braincase and inner ear, is described Thursday in the journal Nature.
Previous studies of the feathered wing and tail of Archaeopteryx and its birdlike anatomy, including a pronounced wishbone, supported the prevailing view of experts that it was capable of some degree of powered flight. Archaeopteryx is considered a prime transitional species in the evolution of some reptiles, probably dinosaurs, into today's birds.
But the research team, led by Angela Milner, a paleontologist at the British museum, wrote that until their investigation of Archaeopteryx, "little was understood about the extent to which its brain and special senses were adapted for flight."