Vegavis iaai was an historical relative of geese and geese, nevertheless it dived for fish like grebes or loons
Mark Witton
A 69-million-year-old cranium present in Antarctica has been recognized as a relative of geese and geese, making it the oldest identified trendy hen.
It belongs to a species that was first recognized 20 years in the past named Vegavis iaai, which lived within the late Cretaceous Interval alongside the final dinosaurs. However as a result of solely fragments of skulls had been discovered beforehand, scientists had been unable to agree what sort of hen it was or whether or not it was as an alternative a bird-like, non-avian dinosaur.
The fossil cranium was found in 2011 on Vega Island, off the Antarctic Peninsula. Nonetheless, it was encased in rock so arduous that excavators needed to spend tons of of hours chipping away on the surrounding stone earlier than it might be scanned to disclose its inside particulars.
Patrick O’Connor at Ohio College, who labored on the evaluation, says two options of the just about full cranium solely ever happen in trendy birds. First, the higher beak is primarily comprised of a bone referred to as the premaxilla, whereas a second bone, the maxilla, is significantly shrunk and contributes to solely a small portion of the bony palate.
Second, in trendy birds, the forebrain is very large relative to the remainder of the mind; in pre-modern birds and near-bird dinosaurs like Velociraptor, these areas are proportionally a lot smaller.
Whereas Vegavis has options that clearly mark it as being in the identical group of waterfowl as geese and geese, it could have regarded very completely different, says O’Connor. The hen’s beak form, jaw musculature and hind limbs recommend it was extremely specialised for diving in pursuit of fish.
“It would probably be easily mistaken for modern grebes or loons, which are only distantly related to ducks and to each other,” he says.
Jacqueline Nguyen on the Australian Museum in Sydney says this historical species has been topic to a number of debate amongst avian evolutionary scientists, however the brand new analysis helps settle the argument.
“Together, [the evidence] suggests that Vegavis looked and foraged quite differently from its duck and geese relatives, and that this may have been an ‘evolutionary experiment’ in the early history of this group of birds,” she says.
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