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ABC March 15 Newsletter.Pub AMADOR BIRD TRACKS Monthly Newsletter of the Amador Bird Club March, 2015 The Amador Bird Club is a group of people who share an interest in birds and is open to all. “home of the rare President’s Message Amadorian Combo Parrot” Hi All, The Amador Bird Club meeting will be held on: I assume that everyone is enjoying our EARLY spring weather. I hear the birds are even Friday, March 13th, 2015 confused and starting their breeding efforts at 7:30 PM earlier, oh well Mother nature fooled us again !!! Enough of my prattling on I need to remind those Place : Administration Building, members who haven't paid their annual dues that Amador County Fairgrounds, they are indeed due. Plymouth Dates of bird club Last month we had an interesting DVD on “A meetings this year: Murder of Crows”, this month I have just received DVD "A selection of from Australia today a DVD on "A Selection of Activity : Finches"? March 13* Finches." I have not yet viewed it but it is April 10** produced by a very knowledgeable avian May 8 specialist named Peter Odekerken. It is a rather Refreshments: Persons with June 12 long DVD of about 1Hr. 20Mins. so we can decide last names beginning with S-Z. July 10 if we want to view it in it's entirety on one night or August 14 do it on two nights. If two nights, it will cover September 11** June’s meeting also, if we decide to view it all on Officers for 2014 - 2015 October 9 one night we will get it rolling hopefully about 7:45 November 13* to allow everyone to get away at a reasonable President Blue Wrigley December 12 hour. I am hoping to get John York to give us a Treasurer Cathy Hooper (Xmas party) presentation for our May meeting, combined with Secretary Terry Ryan our Pizza night. Newsletter Todd Sargent *Friday -the -13 th : drive Enough, actually, probably too much! Webmaster Kim Schmutzler -Agee carefully! See you all again on Fri. 13th ** Semi -Annual —Blue Raffle Membership Dues are Birds and Dinosaurs now Due! As recently as a decade ago, the proposition that birds evolved from dinosaurs was a contentious and unproven issue. After a century of Family $15, Single $10, Jr. $7.50 hypotheses without conclusive evidence, well -preserved fossils exhibiting There is also a new $5.00 postage fee remarkable richness and completeness of feathered dinosaurs were discovered for those who wish to receive the during the 1990s in Liaoning , China. Direct evidence of feathers now newsletter by snail mail. exists for at least 40 species of dinosaur, and evidence of many more Please give dues to Treasurer Cathy at features that lead to the evolution of birds continues to come in. The the meeting or send by mail. following article offers more detail. 1 Amador Bird Club Newsletter March 2015 Feathered Dinosaur From Wikipedia, the free encyclopedia Although growing evidence of the relationship of non -avian dinosaurs to birds raised the possibility of feathered dinosaurs over the twentieth century, it was not until the mid -1990s that clearly non -avian dinosaur fossils were discovered with preserved feathers. Since then, feathers or feather-like integument have been discovered on dozens of genera of dinosaurs via both direct and indirect fossil evidence. The fossil feathers of one specimen of the alvarezsaurid Shuvuuia deserti have tested positive for beta -keratin , the main protein in bird feathers. [1] Fossil of Microraptor gui includes impressions of feathered wings (see arrows) Although the vast majority of feather discoveries have been for coeleurosaurian theropods , the discoveries of integument on at least three ornithschians raise the likelihood that proto -feathers were present in basal dinosaurs, and perhaps even a more ancestral animal, in light of the pycnofibers of pterosaurs . Early Shortly after the 1859 publication of Charles Darwin 's On the Origin of Species , British biologist Thomas Henry Huxley proposed that birds were descendants of dinosaurs. He compared the skeletal structure of Compsognathus , a small theropod dinosaur, and the 'first bird' Archaeopteryx lithographica (both of which were found in the Upper Jurassic Bavarian limestone of Solnhofen ). He showed that, apart from its hands and feathers, Archaeopteryx was quite similar to Compsognathus . Thus Archaeopteryx represents a transitional fossil . In 1868 he published On the Animals which are most nearly intermediate between Birds and Reptiles , making the case. [2][3] The leading dinosaur expert of the time, Richard Owen , disagreed, claiming Archaeopteryx as the first bird outside dinosaur lineage. For the next century, claims that birds were dinosaur descendants faded, with more popular bird - ancestry hypotheses including 'crocodylomorph' and ' thecodont ' ancestors, rather than dinosaurs or other archosaurs . In 1969, John Ostrom described Deinonychus antirrhopus , a theropod that he had discovered in Montana in 1964 and whose skeletal resemblance to birds seemed unmistakable. Ostrom became a leading proponent of the theory that birds are direct descendants of dinosaurs. Further comparisons of bird and dinosaur skeletons, as well as cladistic analysis strengthened the case for the link, particularly for a branch of theropods called maniraptors . Skeletal similarities include the neck , the pubis , the wrists (semi -lunate carpal ), the ' arms ' and pectoral girdle , the shoulder blade , the clavicle and the breast bone . In all, over a hundred distinct anatomical features are shared by birds and theropod dinosaurs. FACT: Other researchers drew on these shared features and other aspects of dinosaur All birds reproduce by laying eggs. biology and began to suggest that at least some theropod dinosaurs were feathered. Eggs vary in size and color The first restoration of a feathered dinosaur was Sarah Landry's depiction of a depending on species. Although feathered "Syntarsus" (now renamed Megapnosaurus or considered a synonym of there is a wide range of egg colors, Coelophysis ), in Robert T. Bakker 's 1975 publication Dinosaur Renaissance .[4] Gregory S. Paul was probably the first paleoartist to depict maniraptoran dinosaurs only two pigments contribute to the with feathers and protofeathers, starting in the late 1970s. color of the shell. The first pigment is derived from hemoglobin and the By the 1990s, most paleontologists considered birds to be surviving dinosaurs and second from bile. Most species lay referred to 'non -avialan dinosaurs' (all extinct), to distinguish them from birds their eggs in a nest. Nests may vary (Avialae ). Before the discovery of feathered dinosaurs, the evidence was limited to in size, shape, and construction Huxley and Ostrom's comparative anatomy . Some mainstream ornithologists, including Smithsonian Institution curator Storrs L. Olson , disputed the links, material, but the most common nest specifically citing the lack of fossil evidence for feathered dinosaurs. shape is cup -shaped. 2 Amador Bird Club Newsletter March 2015 Fossil discoveries After a century of hypotheses without conclusive evidence, well -preserved fossils of feathered dinosaurs were discovered during the 1990s, and more continue to be found. The fossils were preserved in a Lagerstätte — a sedimentary deposit exhibiting remarkable richness and completeness in its fossils — in Liaoning , China. The area had repeatedly been smothered in volcanic ash produced by eruptions in Inner Mongolia 124 million years ago, during the Early Cretaceous epoch. The fine -grained ash preserved the living organisms that it buried in fine detail. The area was teeming with life, with millions of leaves, angiosperms (the oldest known), insects , fish , frogs , salamanders , mammals , turtles , and lizards discovered to date. Sinosauropteryx fossil, first fossil of a definitively non - avialan dinosaur with feathers The most important discoveries at Liaoning have been a host of feathered dinosaur fossils, with a steady stream of new finds filling in the picture of the dinosaur –bird connection and adding more to theories of the evolutionary development of feathers and flight. Turner et al . (2007) reported quill knobs from an ulna of Velociraptor mongoliensis , and these are strongly correlated with large and well -developed secondary feathers. [5] Behavioural evidence, in the form of an oviraptorosaur on its nest, showed another link with birds. Its forearms were folded, like those of a bird. [6] Although no feathers were preserved, it is likely that these would have been present to insulate eggs and juveniles. [7] Not all of the Chinese fossil discoveries proved valid however. In 1999, a supposed fossil of an apparently feathered dinosaur named " Archaeoraptor liaoningensis ", found in Liaoning Province , northeastern China, turned out to be a forgery. Comparing the photograph of the specimen with another find, Chinese paleontologist Xu Xing came to the conclusion that it was A nesting Citipati osmolskae specimen, at the AMNH . composed of two portions of different fossil animals. His claim made National Geographic review their research and they too came to the same [8] Minutes for meeting February 13, 2015 conclusion. The bottom portion of the "Archaeoraptor" composite came President Blue called the meeting to order at 7:30pm. from a legitimate feathered dromaeosaurid now known as Microraptor , and Members in attendance were: Blue, Sarah, Terry, the upper portion from a previously -known primitive bird called Y anornis . Sherri, Jack, Jackie, Chris Virginia, Daryl, Kim and Doug & Ingrid. In 2011, samples of amber were discovered to contain preserved feathers The minutes were approved as written. Terry gave the from 75 to 80 million years ago during the Cretaceous era, with evidence Treasurer’s report in Cathy’s absence. that they were from both dinosaurs and birds. Initial analysis suggests that - - [9] Meeting plans: March ?, April Semi Annual Raffle, some of the feathers were used for insulation, and not flight. More May -Pizza Night & John York complex feathers were revealed to have variations in coloration similar to We adjourned for refreshments and to watch the modern birds, while simpler protofeathers were predominantly dark.
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