Thursday, February 17, 2011

Revealing the Colors of a Dinosaurs Feathers

Dinosaur's True Color Revealed
By Alea DelleCave
I. Introduction:
From the pages of "How do Dinosaurs say Goodnight" to the screens of "Jurassic Park", our minds have been planted with the image of what people think dinosaurs look like. Never have researches been able to find the true colors of them; all we know for certain is the basic structure. The skeletons give us those clues. Guessing and playing around with the color wheel may be a way of the past. Scientists believe that they may have cracked the color-code. They got to work on their first trial, a "bird-like" dinosaur about the size of a chicken. Its color patterns were decoded after researchers used a scanning electron microscope to study pigment samples taken from the fossils feathers from the specimen and then matched it to todays birds.

II. Discovery:
For years we have tried to solve the mystery of Dinosaurs may have looked like, but for the first time in history scientists have discovered how to decode the full body color of certain dinosaurs. Within the research, scientists found color pigments isolated to a few parts of the bodies, using less rigorous methods for assighning colors to the fossilized, filament-like "protofeathers" discovered on the specimens. By learning the colors of the extinct creatures we hope to find an improved sense of knowledge that could lead to a hot insight on how some of the prehistoric predators behaved and why feathers, scales,and furs evolved in the first place.

Our fist case was the Anchiornis Huxlyi, this 155 million year old species, turned out to look like a woodpecker the size of an extremely large chicken chicken! The colorful patterns of "chicken-not-so-little" are "quite similar to the silver-spangled Hamburg chicken, a domestic breed of ornamental chicken," said ornithologist Richard Prum, of Yale University. The Anchiornis is a recent discovery as well, its color patterns were decoded after the researchers had used a scanning electron microscope to study pigment samples taken from fossil feathers all over a specimen and then was compared to samples to pigments from modern birds. Similar to its brother-bird, the woodpecker, Anchiornis also consists of reddish brown, black, grey. and white feathers. This lead to the speculation that perhaps this coloration was used for attracting mates as well, or a form of visual communication, like as todays birds. They feathers found that were elongated first appeared within the fossil record, they were distinctively spotted and striped. Now we obtain patterns within the individual feathers in dinosaurs. "This could have been in lots of contexts, including sexual display, territoriality, et cetera," Prum said. "It could also have been like modern redstarts, which use their bright wing and tail patches to scare up insects, which [the birds] then seize in flight." The scientists found the colors, and determined the shapes by analyzing the shape and density of the melanosomes within the fossil feathers. Melanosomes are nonoscale, pigment-carrying organelles within the little feathers. The microscopic particles were first found preserced in a fossil, similar to the plot line of Jurassic Park only instead this time we only found colors, in our birds today the different melanosomes are known to produce different colors in the feathers.

Scientists from England and China studied many different fossils but only artistically created one. Using the fossil feather melanosomes they found reddish-brown and white stripes on the tail of a small little critter known as a Sinosauroptreyx. Derek Briggs, a co-author of the new study, said, "The other team's (team England&China) report is based on isolated samples from several different taxa, so they can't paint an entire animal." Even so, the earlier study did include a picture of an entire Sinosauropteryx, but any coloration beyond the tail and the crest running along its head and back was artistic guesswork.By contrast, Briggs said, "We have 29 samples from the same specimen, covering the whole plumage." Still, a striped tailed dinosaur only makes us more curious about how other animalia may have looked during this time period. More researchers behind the new study also say that were more meticulous in how they interpreted the pigment samples. Orange is a hard color to study because very few of todays birds seem to be the similar tint. (My guess is because our Anchiornis can be traced to a woodpecker, where the poor little Sinosauropteryx may not have a living relative in todays life.) The Melanosomes found in his tail are all phaeomeloanosomes, this is harder to pinpoint an exact color because of the wide range. Phaeomelanosomes are round and produce colors that range from reddish brown to a yellow. Eumelanosomes are rodlike and are mostly found to be black and grey. A lack of melannosomes makes a white. Not many modern birds have 100% phaeomelonosomes or eumelanosomes in their feathers, so distinguishing color from the phaeomelanosomes can become complicated. Research is still being continued on our friend the Sinosauropteryx.



III. Biography of Investigators:
Richard Prum is an evolutionary ornithologist, meaning he studies the evolution of birds. He also studies phylogenetics, meaning he studies the similarities between different evolving species, behavior, feathers, the structural color, evolution, sexual selection, and the historical bio-geography. Most of his research has included the development and evolution of feathers, finding new tools dedicated to the study of physics an the evolution of structural coloration. He continues to work on the efforts in phylogenetic ethology of polygynous birds. He is the Curator of Ornithology at the Yale Peabody Museum of Natural History, and the Head Curator of Vertebrate Zoology.

Jakob Vinther is a Yale University Grad student. He studies molecular paleobiology, a science that utilizes the evolutionary history found within rocks, and molecules to develop the most supported hypothoses of organismal evolution.

Derek Briggs is the director of the Peabody Museum of Natural History. He studies the taphonomy and evolutionary significance of preserved fossils, decays and minerilazations, molecular preservation, and the Cambrian radiation.





IV: Impact on Humanity
Scientists never thought they would be able to recreate images of dinosaurs that lived over 

64 million years ago. "The reality of what we achieved didn't really sink in until I saw the color reconstruction," stated Briggs. "At that point I felt very emotional, like we had ... brought something back from the dead—or at least gone back in time and taken its picture." Todays research promises brighter more advanced technology for the future. Finding the prehistoric colorations in dinosaurs will provide the role of color within their behavior.Some features, like the crest, might have allowed the dinosaur to attract mates. But white and black limb feathers might have helped Anchiornis escape predators. A number of living animals like zebras use similar color patterns to dazzle predators, so that they can run away.  Thus solving just another piece of the evolution puzzle. Not just birdlike dinos have feathers; many of the reptiles have been discovered to have hairlike fragments, similar to human hair,often
 called dino fuzz,which is linked to bird feathers.  Researchers can intend on a lot more scientific discoveries and progressions as they study more and more into the fossil life of dinosaurs. 
The transformation of mankind's view of dinosaurs from dull to flamboyant was made possible by a discovery by Yale graduate student Jakob Vinther in the Department of Geology and Geophysics. Vinther was studying the ink sac of an ancient squid and realized that microscopic granular-like features within the fossil were actually melanosomes -- a cellular organelle that contains melanin, a light-absorbing pigment in animals, including birds. By knowing the historic background of these animals not only will it give us information on the dinosaurs themselves but  also insight on the type of animal that they may have similarities like. By viewing one of todays birds we can maybe learn some of the certain traits that the dinosaur-ancestors had. 


V. Journal Article:
The National Geographic
True-Colored Dinosaur Revealed
Noted By Andrew Berger   





A team of Chinese and British scientists reported that the first clear evidence of dinosaur colors from studies of 125-million-year-old fossils of a dinosaur called Sinosauropteryx. Many pictures have been painted multiple times, but the colors were products of a painter’s imagination, not a scientist’s laboratory. Dinosaur fossils are mostly drab collections of mineralized bones. A few preserve traces of skin, and fewer still preserve structures that many scientists have argued are feathers.

“We might be able to start painting a picture in color of what these things looked like,” said Lawrence M. Witmer, a paleontologist at Ohio University, who was not involved in the study.

In the new study, Michael Benton, a paleontologist at the University of Bristol, has analyzed the structures of what seems to be prehistoric-feathers and say they match the feathers of living birds down to the microscopic level. They have been using microscopic technology to determine the ancient feathers’ color. Benton used the same mechanism as Mr. Vinther in 2006 had discovered what looked like an ink sac preserved in a squid fossil. Putting the fossil under a microscope, he discovered the sac was filled with tiny spheres. The spheres were identical to pigment-loaded structures in squid ink, known as melanosomes. 

They determined, for example, that a 47-million-year-old feather had the dark iridescent sheen found on starlings today. Starting in the 1970s, a growing number of paleontologists argued that birds had evolved from a two-legged group of dinosaurs called theropods. The paleontologists pointed to traits in their skeletons found elsewhere only in birds. In 1996, Chinese paleontologists discovered an exquisitely preserved fossil of a miniature theropod, called Sinosauropteryx, that had whiskerlike structures on its head and back. Some paleontologists argued that these whiskers were simple feathers. Since then, however, scientists have found a number of well-preserved theropod fossils with many more featherlike structures, corresponding to downy feathers and feathers with vanes. Scientists have even found bumps on the arm bones of dinosaurs, where the quills had attached. If all of these structures really were feathers, Dr. Benton reasoned, then they might have melanosomes. The scientists also looked at a piece of the tail of Sinosauropteryx, one of  the first feathered dinosaur ever found. 

Bibliography:



"Yale Department of Ecology & Evolutionary Biology." Yale University. Web. 17 Feb. 2011. <http://www.yale.edu/eeb/prum/>.

Yale), Michael DiGiorgio/Courtesy. "Dinosaur Had Vibrant Colors, Microscopic Fossil Clues Reveal." Science Daily: News & Articles in Science, Health, Environment & Technology. Web. 17 Feb. 2011. <http://www.sciencedaily.com/releases/2010/02/100204144422.htm>.
Cohpek, Mitch. "Dinosaurs and Their Colors." Science Invesigation: Colors. Web. 17 Feb. 2011. <http://www.nytimes.com/2010/01/28/science/28dino.html>.

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