S. Abramowicz, Dinosaur Institute, NHM
Pictured is an illustration of a newly discovered feathered dinosaur,
As paleontologists increasingly unearth evidence of feathers in prehistoric fossils, our conceptions of what dinosaurs looked like when they roamed the earth has gradually evolved.
Instead of the reptilian appearance we all recognize from childhood toys and films like Jurassic Park, many dinosaurs in fact more closely resembled birds, kind of like this recently discovered little guy, Eosinopteryx brevipenna, a flightless theropod dinosaur that roamed China during the Middle/Late Jurassic period.
Archaeopteryx, also known as Urvogel, the German word for "original bird" or "first bird," was first discovered in 1860 and later fossils of this species presented some of the earliest evidence of flight in these prehistoric animals.
An intermediate creature that was not quite dinosaur but not exactly a bird either when it lived 150 million years ago, Archaeopteryx had teeth, a long tail, and wings capable of flight with claws at the end for grabbing prey.
A century after the discovery of Archaeopteryx, paleobiologists increasingly found anatomical connections between birds and dinosaurs. In the 1970s, artists began to portray dinosaurs with feathers based on accumulating evidence.
Megapnosaurus, shown here, was another species with whom researchers began early to identify with feathers. A lightweight animal that could reach up to 10 feet in length and roamed Jurassic Zimbabwe, Megapnosaurus, also known as Syntarsus, traveled in packs and preyed on small reptiles and fish.
Many of the fossils unearthed that provided evidence of feathers had deteriotated over the eons they remained buried. It wasn't until 2010 that researchers identified color pigments in feathers from dinosaurs and early birds.
Sinosauropteryx, illustrated here, was a theropod dinosaur that had "simple bristles -- precursors of feathers -- in alternate orange and white rings down its tail," according to a description of the study's findings.
Given that so many feathered dinosaurs were in fact flightless, the purpose of the feathers has been a subject of debate. Some dinosaurs may have evolved feathers for social signaling; others had plumage to provide insulation.
In the cases of some dinosaurs, such as the two oviraptors, herbivores related to T. rex that lived during the Cretaceous period, researchers believe the feathers were used for mating displays, similar to modern-day peacocks and turkeys.
Jason Brougham/University of Texas
You might be fooled into thinking the animals in this illustration are something between a murder of crows and a band of blue jays. In fact they are Microraptors that lives more than 130 million years ago.
These four-winged, plumed dinosaurs were no larger than modern-day pigeons and sported iridescent tail feathers.
Researchers believe the shimmering plumage was likely used in mating and other social interactions.
Like the diversity among birds today, not all feathered dinosaurs were lightweight, agile animals. A massive tyrannosaur that lived in China until about 65 million years ago, Yutyrannus huali, meaning "beautiful feathered tyrant," grew up to 30 feet long and could weigh more than 3,000 pounds.
This titanic tyrannosaur, as it was described, significantly increases the size range for feathered dinosaurs.
In a stunning find published in the journal Science in 2011, paleontologists uncovered dinosaur feather preserved in amber that dated back some 79 million years ago.
This discovery provided scientists a new window into the evolution of feathers in terms of structure in the evolutionary timeline from dinosaurs to birds. Even shades of color remained well preserved in the amber.
A new non-avian dinosaur not only looked like a jet but also was an expert flier.
The 125-million-year-old dinosaur, Changyuraptor yangi, strengthens the evidence that flight preceded the origin of birds. The dino, named after researcher Yang Yandong and the Chinese words for “long-feathered raptor,” is described in a study published in the latest issue of Nature Communications.
It's clear that this dinosaur, which sported big wings and a streamlined, aerodynamic body, could fly. The question remains: How did the 4-foot-long animal get off the ground?
“It is difficult to say, and controversial, whether an animal like Changyuraptor was able to take off from the ground or launch from a perch,” project leader Luis Chiappe told Discovery News. “We do know that they were very maneuverable animals and our study shows that they used their tail to slow down while they landed.”
“At a foot in length, the amazing tail feathers of Changyuraptor are by far the longest of any feathered dinosaur,” added Chiappe, a paleontologist at the Natural History Museum of Los Angeles County.
Chiappe and an international team found the dinosaur in the Liaoning Province of northeastern China. Based on multiple recent discoveries there, this site was a hotbed of dino activity back in the Cretaceous, and many of the dinosaurs had feathers.
Changyuraptor looks as if it had four wings instead of the usual two, due to long feathers that jutted out from its legs. Such “four-winged” dinosaurs belonged to a group known as “microraptorine,” or tiny raptors.
Before non-avian dinosaurs went extinct, some of them hunted birds. They also likely ate fish, swooping over bodies of water to catch their dinner. Such moves would have been all the more impressive considering that Changyuraptor weighed 9 pounds. (By comparison, seagulls typically weigh only about 1.5 pounds.)
Picture is an illustration of a newly discovered feathered dinosaur,Changyuraptor yangi.S. Abramowicz, Dinosaur Institute, NHM
“The new fossil documents that dinosaur flight was not limited to very small animals, but to dinosaurs of more substantial size,” Chiappe said.
Archaeopteryx, the iconic early bird, lived approximately 150 million years ago. Birds, therefore, were around for just 25 million years before Changyuraptor emerged -- a drop in the proverbial geologic bucket.
Changyuraptor’s precise evolutionary relationship to birds is unclear at the moment, aside from the fact that it appears to have enjoyed eating them.
“Whether the flight capabilities of Changyuraptor and its kin evolved independently to the flight capabilities of birds is controversial,” Chiappe said. “Most likely, some of the aerodynamic features we see in Changyuraptor -- like the large forewings -- are the result of the same evolutionary event.”
Chiappe agrees with other studies concluding that pre- or proto-feathers first evolved for thermoregulation. Feathers then appear to have evolved into larger structures that could have served more than one purpose.
The new dinosaur’s color remains unknown at present, but the dino might have flashed striking, multiple colors. Feathers could then have been used during mating displays as well as for flight.
The plane-resembling Changyuraptor’s tail feathers therefore might have impressed the flier’s potential mates, in addition to helping decrease the speed of descent to ensure safe landings.
“It makes sense that the largest microraptorines had especially large tail feathers,” said Michael Habib, a researcher at the University of Southern California. “They would have needed the additional control.”