Feathered Velociraptor? Untangling the Spin

Discoverers admit this could be a flightless bird. That’s not the only problem.

A near-complete skeleton of a “feathered dinosaur,” dubbed Zhenyuanlong, has been announced from China’s Liaoning province. The open-access scientific paper by Junchang Lu and Steven Brusatte appears in Nature’s journal Scientific Reports.  Once again, it was donated by “a local farmer, who is not willing to reveal his identity.” The five-foot-long creature has modern-looking feather impressions on its body, arms and tail, but its arms are too short, the authors say, to have allowed it to fly. A Chinese artist’s painting of a toothed creature running through a forest with a variety of multicolored feathers was quickly reproduced by the news media.

Most of the reports are spinning the fossil as a stepping stone to birds, claiming that feathers appeared for some other purpose before flight. They’re also pointing out resemblances to Velociraptor, the terrors of Jurassic World.

• “‘Big Bird’ dino: Researchers discover largest ever winged dinosaur” (Michael Balter in Science Magazine).
• “Feathered cousin of movie star dino found” (University of Edinburgh)…. “a close cousin of Velociraptor, which was made famous by the Jurassic Park films.”
• “Dinosaur find: Velociraptor ancestor was ‘winged dragon'” (Victoria Gill at the BBC News).
• “Velociraptor’s Cousin Flaunted Fabulous Feathers, Tiny Arms” (Laura Geggel on Live Science). She gets into storytelling mode: “A flamboyant cousin of the fearsome Velociraptor, covered in layers of showy feathers from head to tail, once stalked meaty prey in the forests of what is now northeastern China.” (It should be noted that the colors are all artistic license; the fossil is chocolate-brown in color.)

In The Conversation, paper co-author Steven Brusatte describes how “a new dinosaur helped us prove Velociraptors had feathers.” His “fluffy feathered poodle from hell” is not a simple fossil to explain. Sometimes Brusatte is cocky and confident:

Dinosaurs such as Zhenyuanlong and Velociraptor are some of my favourite fossils to study. They fascinate me because they capture evolution in action. These small, fast-running, brainy predators are some of the closest relatives of birds. They are chapters in one of the greatest stories in the history of life: the evolutionary transition between fearsome carnivorous dinosaurs and their 10,000 feathered descendants that live on today, all over the world.

But then he has serious questions that undermine that confidence:

And this is why the discovery of Zhenyuanlong is really important. It gives us new insight into this incredible moment in evolution. Zhenyuanlong is fairly large for a close relative of birds, two metres long from snout to tail. It also has much shorter arms than Velociraptor or birds. A big, short-armed animal probably wasn’t flying, so what was it doing with its wings? We don’t know for sure.

This opens up a whole new mystery for us to solve: why did wings evolve? Did they evolve for flight, or did they first develop for something else, and were later co-opted to be used as an airfoil? We don’t know the answer yet, but since new fossils of bird-like dinosaurs are being found at an incredible rate, maybe we’ll have it solved by the time the next Jurassic Park comes out.

Brusatte points out that some 50 “feathered dinosaur” species have been found in China. Why there, and so few in other parts of the world? Archaeopteryx (from Germany) is a notable exception, but its affinity to dinosaurs is debatable. “There are over 50 non-avialan paravians currently known from reasonable fossils, and these exhibit a great range of size, osteology, limb proportions, and integumentary covering.”

Flightless Bird?

Is there another explanation for this creature? Maybe it wasn’t evolving from dinosaurs to birds, but represents a bird that lost its ability to fly. Michael Balter entertains that possibility:

What were they used for? One possibility, the researchers say, is that Zhenyuanlong evolved from dinosaur ancestors that could once fly, similarly to the way that flightless birds like today’s ostriches and penguins evolved from flight-capable forebears. But more likely, they think, the wings and feathers served some other function, such as appealing to the opposite sex—much as peacocks do today—or keeping itself or its eggs warm.

The University of Edinburgh piece concurs: “The species may have evolved from ancestors that could fly and used its wings solely for display purposes, in a similar way to how peacocks use their colourful tails, researchers say.” In jargonese, the paper says, “Alternatively, the integumentary similarities between small and clearly volant [flying] dromaeosaurids and larger and presumably non-volant dromaeosaurids could suggest that the larger and short-armed Zhenyuanlong evolved from more volant ancestors and maintained a many [sic] aspects of the integument through the inertia of common descent or for other selective reasons, not because it needed them for flight.”

Another problem is that Brusatte has to appeal to “convergent evolution” to explain the short arms. “Liaoning dromaeosaurids may simply be a grade on the line to velociraptorines and dromaeosaurines, and short arms may have evolved multiple times in this grade.” The family tree, furthermore, is not clear: “Regardless of the precise phylogenetic relationships of dromaeosaurids, Zhenyuanlong provides the first glimpse of feather morphologies in a short-armed dromaeosaurid.”

We want to know why all these “feathered dinosaur” fossils turn up in one province of China, where anonymous farmers find them. If Xing Xu has a racket going in fossil fraud, this could be a bigger hoax than Piltdown Man. There are reasons to think something rotten is up. If these creatures could fly or run, but were less than birds, they should turn up on other continents. The scientists should dig them out of strata of known provenance—no middlemen should be involved. Is money being traded? Did hoaxsters learn their lesson from Archaeoraptor and learn how to fool the scientists better? If you think peer-reviewed scientific papers are infallible, recall that there were about 50 scientific papers published on Piltdown Man. We can’t say at this point how many, if any, are legitimate, but we reserve judgment till these questions are answered.

In the meantime, this could be another flightless bird. Don’t be misled by the artwork and stories told about the creature’s lifestyle as a predator or flamboyant dancer. Notice all the mysteries that Brusatte and his pals cannot answer. There’s enough smell here to avoid jumping on the bandwagon.