Dr. Bortrum
02/25/2010
Dino Color and Snow Talk
This past week my wife and I indulged in one of our favorite dishes, Kentucky Fried Dinosaur, original recipe. I know it's healthier to eat the grilled version but hey, in our eighties and with the crummy winter weather we've had, we deserved a treat. I apologize for trying to be cute by using KFD for KFC, but it is widely accepted that chickens and other birds are the only remaining members of the dinosaur family around today. Last month, two papers made news by not only strengthening the link between birds and dinosaurs but also providing evidence that at least some dinosaurs were more striking in appearance than we've been led to believe. Most dinosaurs that I've seen portrayed in artists' renderings or in museum models are shown in blah shades of brown, green or gray.
To my knowledge, we really haven't had any clues as to the true color of dinosaurs. After all, most fossils millions of years old are just bones or fragments of bones and any bits of skin typically would not have preserved the original color. Now, in work published in January online in Nature, lead author Fucheng Zhang and colleagues at the Institute for Vertebrate Paleontology and Paleoanthropology in Beijing, and from the UK and Ireland, show that one dinosaur was rather colorful character.
I looked up the abstract of their paper and these researchers found melanosomes, notably eumelanosomes and phaeomelanosomes, preserved not only in the pennaceous feathers of early birds but also in integumentary filaments of non-avian dinosaurs. Well, I admit I had to get out my dictionary. "Pennaceous" - the adjective based on "penna" - any of the outer feathers forming the general covering, or contour of a bird. "Melanosome" - not in my dictionary nor in my spellchecker. However, melanosomes are pigment-bearing organelles. "Organelle" - a discrete structure within a cell... with an identifying molecular structure. "Integumentary" - adjective based on "integument" -an outer covering, as of the body or of a plant; skin, shell, husk, rind, etc. I imagine that my readers are generally familiar with such terms but Old Bortrum is indeed old and his once sharp memory is but a shell of its former self. OK, aside from "organelle", I don't recall ever using any of the other words.
For more lucid interpretations of this work and the paper to be discussed below, I turned to articles by Richard Stone in the January 29 issue of Science and by Chris Sloan posted online on January 27 on the National Geographic News Web site. Zhang and his team looked at fossils of birds and dinosaurs over a hundred million years old and found pigment-bearing melanosomes in the feathers of bird fossils between 120 and 131 million years old. This was not the first time melanosomes were found in old bird feathers; a Yale grad student, Jakob Vinther and coworkers reported finding them in 2008. On hearing of the Vinther finding, the Beijing team, with access to a relative plethora of well preserved specimens in fossil-rich Liaoning province, soon found melanosomes in their bird specimens as well.
Could they find them in dinosaurs? The answer, of course, is yes. Of special interest was a "fuzzy" dinosaur known as Sinosauropteryx (let's call it "Sino" for short). Sino was a turkey-size meat-eating dinosaur whose "fuzz" consisted of hairlike filaments about the diameter of human hairs. Skeptics have claimed that such fibers are the remains of collagen fibers from inside the bodies of the fossilized dinos. An alternate view has been that these fibers are protofeathers, the precursors to actual feathers found in later dino fossils.
Well, Zhang and his coworkers found pigment bearing melanosomes in the fuzz of Sino. In particular, they found the aforementioned eumelanosomes and the phaeomelanosomes. They didn't actually see the colors of the fuzz. However, eumelanosomes contain the pigment eumelanin, which is associated with a gray or black image. The phaeomelanosomes contain pheomelanin, associated with a chestnut to reddish brown color. The abstract of the Nature paper states that the melanosomes are preserved "in life position". In Stone's article, Sino is pictured as an orangish brown creature with its long tail covered by bands of this color alternating with lighter whitish bands.
The finding of the pigments in the fuzzy protofeathers pretty much rules out the fuzz being decayed collagen and places the fuzz on its way to becoming feathers. It's only been within the past couple of decades that feathered dinosaurs were found. Why the evolving feathers in an animal that couldn't fly and apparently didn't need them for insulation? Speculation is that the colors of the fuzz/feathers served at first as a display, possibly to attract a mate. It was only later that the feathers really evolved into flight duty and to serve as insulation. Could the precursor to the male peacock's showy display have been a male Sino waving his colorful tail at a female Sino?
Last month's other significant paper in the bird-to-dinosaur story was a paper in the January 29 issue of Science by Jonah Choiniere and colleagues at George Washington University with, again, workers at the Institute of Vertebrate Paleontology and Paleoanthropology in Beijing. Although it seems generally accepted that birds evolved from dinosaurs, there have been those who maintain that birds evolved separately. There is one group of dinosaurs called Alvarezsauroidea, which has been troubling in the sense that some members of this class of dinosaurs have been thought by some to have been flightless birds, not true dinosaurs.
As I understand it, the first known bird, the Archaeopteryx, sort of appeared in the fossil record out of nowhere and didn't clearly have a dinosaur predecessor. What the Science paper does is to extend the Alvaerezsauroidea group back in time by some 63 million years with the finding of a nearly complete fossil, Haplocheirus sollers. This fossil predates Archaeopteryx by 15 million years and its features are stated to be definitely not bird-like. The finding of this early definitely non-bird in the Alvarezoid group, which later does include bird-like critters and firms up more definitely the dino-evolving-into-bird scenario.
I will continue to enjoy my Kentucky Fried Dinosaur!
As I'm getting ready to post this column, it's pouring down snow once again here in New Jersey and those "winter blues" so prevalent here promise to linger even longer. Earlier this week, I missed our weekly Old Guard meeting due to another wintry mix outside and to my wife not feeling well and possibly needing my attention. However, I did make last week's Old Guard meeting, which fell on another day hosting a significant snowfall. That day, I felt compelled to show up inasmuch as I had promised to be a backup speaker in case inclement weather kept the scheduled speaker from making the trip from his home down on the Jersey shore.
The speaker was former Bell Labs colleague George Smith, a 2009 Nobel Laureate in Physics, as noted here in a column last year. Ten minutes into the meeting, during the reading of the minutes of the previous meeting, still no George and I realized I might have to deliver an ill-prepared talk on light-emitting diodes. I ducked out to go to the restroom and, fortunately for me and for the 85 members of the audience who braved the snowy weather, there was George. In addition to encountering heavy traffic on our Garden State Parkway, he had taken a wrong turn and found himself headed to New York before turning around and finding his way to our meeting!
George and Janet, his partner who sailed around the world with him in his boat for 17 years, covering some 55,000 miles, alternated talking on their experiences in Stockholm for the Nobel ceremonies. It was a rare chance to hear and see (they had slides) what goes on during Nobel week if you're so fortunate as to have won the prize. Champagne flowed liberally at virtually every occasion, which ranged from a cozy dinner for some 1700 people to a private dinner for the awardees and families with the king and queen. If I recall correctly, there were only about 170 at that dinner and George was seated next to the queen.
George and Janet had a "handler" and a chauffeur assigned to them for the week and they were provided with a printed schedule laying out their activities for the week, with the proscribed dress for each occasion. Janet said she had engaged an expert from Nordstrom's to advise her on her selection of gowns and other attire and that Nordstrom's had done a fine job. George's attire ranged from tails to "loungewear", which, contrary to the scruffy type of lounging apparel I wear, consisted of a black suit, more like a tuxedo.
As they were all packed and ready to depart for the airport, a musical group, I may be wrong but I think it was called Santa Lucia, arrived in their room. They were serenaded with heavenly music by this white-robed or gowned group as a going away memory of their time in Stockholm.
Well, the snow has piled up several inches while I've been writing about Stockholm. If we ever dig our way out of this mess, I hope to be writing another column next month, anticipating posting it around or before March 31.
I will post this column now, hoping that Brian Trumbore's prediction does not prove true. Arriving yesterday with flashlights, batteries, packs of bottled water, a loaf of whole wheat bread, olive oil and other assorted food items for us, he forecast power failures and two feet of wet snow! Those who read Brian's Week in Review column will know he tends to be on the bearish side.
Allen F. Bortrum
