The right wing of a newly described primitive bird.
Photo courtesy of Oliver Rauhut
Nicholas CarterPhilip J. CurrieThe assortment of prehistoric birds is constantly growing. For many folks, the line between avian and non-avian dinosaur is often drawn at the famous Archaeopteryx, long held as the first ‘true’ bird. Many proto-bird discoveries over the past few decades, however, have knocked ‘Arky off its perch, and this month has seen the description of a new one.Alcmonavis, described by Oliver Rauhut and colleagues, is the latest in small feathered dinosaurs (Rauhut et al., 2019). This bird was found in the same limestone rocks in Germany that yield Archaeopteryx as well, but unlike some of the spectacularly complete specimens of that dinosaur, Alcmonavis is only known from a single right wing.The bones of this wing, however, are distinctly different from that of Archaeopteryx. It looks like Alcmonavis had much larger muscle attachment points and strongly-built digits on its wing bones than its more famous contemporary. Like modern flying birds, Alcmonavis had enlarged crests on its limb bones that allowed for stronger muscles to power the down-stroke of the wing, one of the more energy-demanding parts of flight. Modern birds also have fused ‘hand bones’, with the second digit being the most robust and the others reduced to splints or less. While Alcmonavis doesn’t have this fusion in its hand bones, its second digit is much larger than the others, showing a crucial step in the evolution of the avian wing. This tell us that Alcmonavis is actually a slightly more advanced bird than Archaeopteryx, and was probably a more competent flyer as well.Alcmonavis is also a much larger bird, being 220% larger than the smallest Archaeopteryx ever found and 111% larger than the biggest Archeaopteryx. Perhaps, in order to avoid direct competition, the size and flight abilities of Alcmonavis allowed it to go after different sorts of prey or habitats than Archaeopteryx. Who knows what other primitive birds await our discovery in the German quarries. As more and more are found, perhaps Archaeopteryx won’t be viewed as the benchmark for birddom by future generations. In the grand scheme of things, though, it hopefully won’t lose its importance to the history of science.Upcoming Philip J. Currie Dinosaur Museum EventsMay 31, 10:00 AM – 4:00 PM: Dino Story Time. Join us once a month for a live reading of a story hand-picked by our Dino Team. This month’s theme is best friends! We will be reading “How to take care of your dinosaur” and doing a craft to give to your best friend!June 1, 6:00 PM – 8:00 PM: Summer Jams featuring b2.June 6, 6:00 PM: The River of Death and Discovery Dinosaur Museum Society will hold its Annual General Meeting on Thursday, June 6, 2019 at 6:00pm. All society members in good standing are invited to attend and participate in growing Alberta’s newest dinosaur museum.June 7, 9:00 AM – 4:00 PM: Looking for something to do on those long days off from school? Come spend the day at the Philip J. Currie Dinosaur Museum’s PD Day camp and enjoy a day full of dinosaur-themed fun!June 15, 6:00 PM – 8:00 PM: Summer Jams featuring Matt PattershukJune 22, 1:00 PM – 3:00 PM: Fossil Identification Day. Come and learn about fossils in your area from a paleontologist. Join Assistant Curator, Derek Larson and learn about Alberta’s fossil heritage. Bring your fossils along for identification.June 22, 3:00 PM – 4:00 PM: Lecture Series with Paul Hvenegaard – Monitering the Bull Trout Spawning Run in Lynx Creek. This ACA sponsored lecture will include project highlights that define spawning areas, determine spawning frequency and fidelity, as well as highlight the conservation importance of Lynx Creek.Try your hand at working with real dinosaur bones. The Fossil Preparation Lab Volunteer program is running Tuesdays-Thursdays and the first Saturday of the month from 10 a.m. to 5 p.m., and Fridays from 1–7 p.m. For a posted schedule, see dinomuseum.ca/programs/public-programs/fossil-preparation-lab/.