Rare Bird Fossil Discovered in Museum Storage

first_img Egg Fossils Provide Glimpse Into Prehistoric ParentingBoy Uncovers Rare Woolly Mammoth Tooth Outside Ohio Resort A 75-million-year-old fossil, found in Utah, represents the most complete enantiornithine (en-an-tea-or’-neth-een) skeleton discovered in North America.Uncovered in 1992 by University of California, Berkeley, paleontologist Howard Hutchison, the fossil remained relatively untouched in the University of California Museum of Paleontology at Berkeley—until doctoral student Jessie Atterholt got her hands on it nine years ago.In collaboration with leading enantiornithines expert Jingmai O’Connor, Atterholt and Hutchison found that the turkey vulture-sized creatures were aerodynamic equals of the ancestors of today’s fowl.“We know that birds in the early Cretaceous, about 115 to 130 million years ago, were capable of flight but probably not as well adapted for it as modern birds,” according to Atterholt, now an assistant professor and human anatomy instructor at the Western University of Health Sciences in California.Fossilized wishbone of Mirarce eatoni (via David Strauss/UC Berkeley)“What this new fossil shows is that enantiornithines, though totally separate from modern birds, evolved some of the same adaptations for highly refined, advanced flight styles,” she said in a statement.Certain fossilized features—a deeply keeled breastbone and V-shaped wishbone—mirror aspects of modern birds, suggesting enantiornithines in the late Cretaceous were just as advanced as today’s flying animals.So why did they die off with the dinosaurs, while ancestors of contemporary birds didn’t?“One of the really interesting and mysterious things about enantiornithines is that we find them throughout the Cretaceous, for roughly 100 million years of existence, and they were very successful,” Atterholt said. “We find their fossils on every continent, all over the world, and their fossils are very, very common in a lot of areas—more common than the group that led to modern birds.“And yet modern birds survived the extinction while enantiornithines go extinct,” she added.One possible explanation is that enantiornithines were primarily forest dwellers. So when an asteroid struck Earth, burning the woodlands and signaling the end of the Cretaceous period, the feathered creatures disappeared, too.“We need to do really rigorous studies of enantiornithines’ ecology,” Atterholt explained, “because right now that part of the puzzle is a little hand-wavey.”Skeletal reconstruction of Mirarce eatoni (via Scott Hartman/UC Berkeley)No stranger to bird fossils, Hutchison stumbled on the nearly complete specimen, eroding out of the ground in the Kaiparowits formation in Utah’s Grand Staircase-Escalante National Monument.Despite early interest, the fossil fell by the wayside, laying untouched in storage for nearly 20 years.“Over the moon” to take on the project, Atterholt and her colleagues named the species—among the largest North American birds from the Cretaceous—Mirarce eatoni.The title pays homage to the detailed preservation of the fossil and mythical Greek winged messenger Arce; it also honors Jeffrey Eaton, a paleontologist who has worked for decades on fossils from the Kaiparowits Formation.The team’s fossil analysis was published this week in the open-access journal PeerJ.More coverage on Geek.com:New Dino Discoveries Missing Link Between PredatorsThese Songbirds Use Brute Force to Kill Prey Twice Their SizeAncient Dinosaur Movement Could Inform Modern Robotics Stay on targetlast_img

Leave a Reply

Your email address will not be published. Required fields are marked *