Though modern-day birds sport a coat of streamlined plumage, it turns out that their ancient relatives were surprisingly fluffy.
In a new study, published in the journal Paleontology, researchers from the University of Bristol in the United Kingdom compared the well-preserved fossilized feathers of the crow-sized, bird-like dinosaur Anchiornis to those of other dinosaurs and extinct birds, discovering that the ancient feathers are much "shaggier" than their modern avian relatives.
Anchiornis is an early member of the paraves, a group that includes true birds as well as feathered dinosaurs, according to the university press release. Originally thought to be a bird, Anchiornis has long fascinated and puzzled researchers due to both its similarities and many differences to modern birds, Jason Bittel reported for National Geographic earlier this year.
In the latest study, researchers found that the feathers covering Anchiornis' body had short quills with long, independent, flexible barbs sticking out at low angles in two opposing blades. This organization results in an overall forked shape for each feather and likely produced a surprisingly fluffy and soft texture.
In contrast, the feathers of modern birds are "tightly zipped," according to the press release. This means that the fluffy ancient creatures likely had a more difficult time repelling water. The ancient feathers also appear less aerodynamic, which would have made Anchiornis a less-nimble flyer. But the downy layer likely kept the creatures warm.
The four-winged Anchiornis also sported elongated feathers arranged in a fringe across the backs of their limbs and tail—an arrangement the researchers believe would make the creatures more effective gliders than fliers.
"Overall, it does suggest that truly modern feathers and wings could have evolved later in time or in extinct bird lineages more closely related to modern birds than we might have expected," Evan Saitta, a paleontologist at the University of Bristol in the United Kingdom and author of the new study, tells Dan Robitzski of Live Science.
The latest study is helping scientists tease through the details of not only the physiology but also the behavior of early birds, Saitta explains in the press release. “It’s really exciting to be able to work with the scientists at the forefront of these discoveries, and to show others what we believe these fluffy, toothy almost-birds looked like as they went about their Jurassic business,” Saitta says.
To help further visualize the ancient beasts, the team collaborated with Rebecca Gelernter, a scientific illustrator and graphic designer, to create a life-like image of the animal. Anchiornis’ color patterns were derived from previous fossilized pigment studies, and other previous studies have depicted its wing feathers’ multi-tiered layering, according to the university press release. In this case, the creature’s flesh has been recreated by looking closely at the fossil beneath laser fluorescence.
“As a result of this study and other recent work, this is now possible to [visualize Anchiornis to] an unprecedented degree," Saitta says in the release. "It’s easy to see it as a living animal with complex behaviors, not just a flattened fossil.”
This latest study adds to the mounting evidence that many ancient dinosaurs sported coats of feathers. For example, the Velociraptor, a fleet-footed dinosaur that was depicted as a sleek lizard in the film Jurassic Park, actually had feathers, according to a 2007 study of one of the creature's forearms.
The latest find continues to work against the Jurassic Park vision of dinos, deepening our understanding about how these creatures looked and functioned.