B+Team

=Feathered Dinosaur and Birds=

Team Members: Amanda, Brian, Carrie, Melinda, Melissa, Niel, Ryan, Sabrina, Wendy
**Introduction** This report explores the connection between dinosaurs, namely theropods, and modern birds. In our exploration we well be examining topics like: feathered dinosaurs, the origin of feathers (the evolution of feathers), what is a bird and what is known about the first “bird”, the transition from theropods to birds, and the origin of birds that link it to theropod dinosaurs. There is a paleontologist saying that we've come to agree with: If it acts like a bird, and has the structure like a bird, it must be a dinosaur.

A. What do we know about the evolution of the feathered dinosaurs, what are some of the discoveries of feathered dinosaurs and who discovered them? - Melinda, Niel? Feathered dinosaurs --Niel In the search for the connection between birds and dinosaurs it is important to investigate dinosaurs with feathers. The first bird is known to be. One of the great discoveries that has linked dinosaurs to birds is the fact that in china a dromaeosaur was found that has remiges. “Remiges are like the flight feathers of birds, with a central stiffening vein from which branched fibres radiate.”( Xing Xu) T his shows that there were not only feathered dinosaurs but some of them may have been capable of flight. In China there have been discoveries of two dinosaurs that are thought to have feathers, Scansoriopteryx and Epidendrosaurus; these are “the first undoubtedly arborial (tree-climbing) dinosaurs” ( Xing Xu). There is a lot that is not confirmed about these dinosaurs from what time they were living to even the possibility that they were the same species. Oviraptorosaurs are thought to have feathers because of how the bodies have been shaped. ( Xing Xu, ) One type of Oviraptorosaur named Nomingia has a short tail that is similar to that of a birds, the main similarity is the “pygostyle”( Xing Xu). This is used in modern bird to turn tail feathers, because of this scientists think that the nomingia has feathers because of this specific use.
 * 1. Feathered Dinosaurs**

URLs: http://www.geocities.com/dannsdinosaurs/featothr.html#Cryptovolans Xing Xu, M.A. Norell, Xuewen Kuang, Xiaolin Wang, Qi Zhao & Chengkai Jia 2004 "Basal tyrannosauroids from China and evidence for protofeathers in tyrannosauroids." [|//Nature// 431: 680-684]

B. What do we know about why feathered dinosaurs evolved the way they did, and what are the ideas about the origin of feathers? -- Brian It is safe to say that everyone that is able to see can tell you what the average bird looks like. They have two wings, two feet, a beak, and lots of feathers. Though birds have a specific type of skeletal structure, the one thing that makes them truly unique is their feathers. No other creature currently living has feathers, making feathers an evolutionary novelty. This novelty can be dated back to the Late Jurassic, but is hypothesized to be older still - just no fossil or well enough preserved fossils exists currently to establish a firm missing link in the transition from reptilian scales that belong to the dinosaurs to the feathers we know of today. Though we may not be able to date the time frame that feathers first began developing we can track the evolutionary process of feathers from fossils found in both Germany and China (where some of the oldest specimens of fossilized feathers have been discovered) to get a rough estimate. The first theropod discovered with feathers, and also one of the most studied, is Archaeopteryx from the Bavaria, who was fully covered in feathers. Since the time of this discovery many others have been found - even some that are older. Though Archaeopteryx is from the Late Jurassic much of the recent study has been from fossils found in the Liaoning Province in northeast China. These records are primarily from the Early Cretaceous (110-139.4 million years ago), where fossils of dinosaurs that are closely related to birds and of real birds have been found. One of the unique features of fossils from this area is that not only are the bones preserved but so too are feathers and other soft parts. The evolution of feathers was once though to of been a divergence from scales. This does not seem likely as they are not directly homologous (made of the same base compounds). Instead a five step process is currently the accepted evolutionary process that helped develop the first feathers.
 * Origin of Feathers**

Graphic from Mark A. Norell and Xing Xu article //“Feather Dinosaurs”// found in the //Annual Review of Earth and Planetary Science//; 2005; 33 Platinum Full text Periodicals pg. 277//.// 1. The process starts off with hollow tubes forming from follicles, or the adaption from scales to having follicles. 2. The calamus (tubes) adapted into having a series of barbs (similar to the feathery part of a feather) along them. 3. The barbs organized along a rachis (the central shaft of a feather that extends from the calamus). 4. The development of barbules, which gives feathers the ability to self organize and allows the barbs to adhere to one another. 5. Is the further development of general feathers into more specific feather, for example the different flight feathers. Though this process is the most accepted it is also hypothesized that above process was not quite this straight forward. Many other divergences could have taken place to include regression to previous stages. With the fossil record still being incomplete it is hard to be completely certain what the exact time scale of this progression would have been, and how many other processes were tried by nature before true feathers were formed. It is also uncertain how the initial formation of feathers led to the formation of more specialized feather that in turn led to flight, or the other various special function that modern feather cater to. Though none of the theories as to why the dinosaurs, particularly the theropods, developed feathers can be proved at this time, they can prove to be an interesting topic for discussion and thought.
 * Current thoughts on why feathers evolved:**
 * 1) The development of feathers was much like the development of hair in mammals; it would help keep the dinosaurs warm.
 * 2) Everything from the barbs to the feathers themselves were found attractive and help the dinosaurs with them mate. This over the many generations would have weeded out all of those without feathers in that species.
 * 3) Some scientists have proposed the idea that feathers evolved to assist some of the smaller theropods in catching insect prey.
 * 4) Smaller theropods might of developed feathers to maintain body temperature, since many types of them were believed to be miniaturizing.
 * 5) Genetic mutations may have been the cause and not a natural process for the original formation of feathers. This has been experimented with by introducing an outside agent to get the scales on a birds feet be feathery. This is a valid theory sense both dinosaurs and crocodilians are related.

Picture of Sinornithosaurus fossils.

Close up photo showing the barbules and calamus Sinornithosaurus.

Above graphics from Xing Xu, Zhong-he Zhou, and Richard O. Prum article //“Branched integumental structures in Sinornithosaurus and the origin of feathers”// Found in “Nature, Vol 40, 8 March 2001.

URLs: Fabulous Fossil Strengthens Dino-Bird Link." __Current Science__ 87.1 (2001): 12-13. __Education Module__. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=12&did=78904776&SrchMode=1&sid=1&Fmt=3&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202240237&clientId=79571 Mayr, Gerald, Burkard Pohl, and D Stefan Peters. "A Well-Preserved Archaeopteryx Specimen with Theropod Features." __Science__ 310.5753 (2005): 1483-86. __Research Library Core__. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=1&did=942798921&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202237440&clientId=79571 Norell, Mark A., and Xing Xu. "Feathered Dinosaurs." __Annual Review of Earth and Planetary Science__ 33 (2005): 277-99. __Platinum Full Text Periodicals__. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=3&did=857758811&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202237440&clientId=79571 Poling, Jeff. "Feathers, Scutes and the Origin of Birds." __Dinosauria.com__. 18 Nov. 1996. 10 Feb. 2008 http://www.dinosauria.com/jdp/archie/scutes.htm Xu, Xing. "Feathered Dinosaurs from China and the Evolution of Major Avian Characters." __Integrative Zoology__ 1.1 (2006): 4-11. __Google__. Blackwell Synergy. 4 Feb. 2008 http://www.blackwell-synergy.com/doi/pdf/10.1111/j.1749-4877.2006.00004.x?cookieSet=1 Xu, Xing. "Palaeontology: Scales, Feathers and Dinosaurs." __Nature__ 440.7082 (2006): 287-288. __Research Library Core__. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=0&did=1013273891&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202237440&clientId=79571 Xu, Xing, Zhong-he Zhou, and Richard O. Prum. "Branched Integumental Structures in Sinornithosaurus and the Origin of Feathers." __Nature__ 410.6825 (2002): 200-04. __Reasearch Libary Core__. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=13&did=69920404&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202240237&clientId=79571 Yu, Mingke, Ping Wu, Randall B. Widelitz, and Cheng-Ming Chuong. "The Morphogenesis of Feathers." __Nature__ 420.6913 (2002): 308-12. __Reasearch Libary Core__. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=10&did=245919421&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202240237&clientId=79571

C. Still to be determined topic -- Amanda The question of early birds and there relation to dinosaurs and why they are living today and dinosaurs are extinct is one of many debates. There is a lot of research and suggestion towards different reasons why birds are not extinct and the dinosaurs of 65 million years ago are. The extinction of dinosaurs was not a single catastrophic event but a series of events. There are 335 known species of dinosaurs and no one species lived longer than two million years. After each group of dinosaurs became extinct a new group would arise. Sixty five million years ago a new group did not replace the dinosaurs from the cretaceous. Some believe this to be the last of the dinosaurs but others have found that they are not extinct, but alive today. The theory that dinosaurs are not completely extinct is a very controversial issue. Many believe that the last dinosaurs to die out 65 million years ago were in fact replaced by a new group, birds. This theory has a very strong support but a frequently studied draw back is; how come birds survived and dinosaurs did not? There are two scenarios that researchers have concocted. The first is that birds signify a branch of the dinosaur ancestry that survived the extreme cretaceous extinction and have evolved into the birds of today. The second scenario could be that birds and dinosaurs had a common ancestor that gave dominance to both groups, this follows the theory of natural selection. This second idea continues to present that birds were never dinosaurs but are actually the closest living species to dinosaurs.
 * Early Bird Extinction**

URLs:

A. What is a bird and what do we know about the "first bird"? -- Carrie Birds are warm-blooded vertebrates belonging to the class Aves. They possess feathers and have modified forelimbs that form wings, although their wings are not always used for flight. In addition to these and other skeletal features, ovulating female birds have medullary bone. This specialized bone prevents severe calcium loss during egg formation and has also been found in theropod dinosaurs. Birds lay hard-shelled amniotic eggs and have a hard bill that covers the jaw. They also have a four-chambered heart and a highly efficient respiratory system. Birds are thought to have evolved from the theropod dinosaurs. The ancestors of birds were terrestrial, bipedal, carnivorous or omnivorous, and also possessed features commonly thought of as belonging to birds, like a wishbone and feathers. They also shared the elongated forelimb and lateral flexing wrist found in later birds, as well as other features like hollow bones whose origins predated flight. The closest living relatives to modern birds are Crocodilians, and the closest non-avian dinosaur relation is thought to have been the Dromaeosaurs. The oldest member of the class Aves, and earliest recognized bird, is Archaeopteryx. Several well-preserved specimens from a variety of species of Archaeopteryx are known from the Late Jurassic. Archaeopteryx was approximately the size of a medium-sized modern bird, like a pigeon or dove. At the time that Archaeopteryx were living, the sites where they have been found were part of a marine lagoon. The lagoon was surrounded by a series of low, subtropical and semi-arid islands that were probably shrub covered, but do not show evidence of trees. Archaeopteryx had several skull and skeletal features that link it to modern birds, but it also retained many intermediate or theropod-like features. There is some controversy over whether or not Archaeopteryx was in fact a flight-capable dromaeosaur, but these arguments have been refuted by the presence of derived characteristics that are shared with birds. Archaeopteryx feathers were asymmetrically vaned, indicating flight. Archaeopteryx lacked the muscle attachments to have been a strong flier, but it was capable of downstroke wing flapping and gliding. Due to the preservation conditions, it is unclear whether or not the head and body were entirely covered by feathers or not, but wing and tail feathers were well-preserved. Its feet were not adapted for perching. Archaeopteryx possessed a short, hyper-extendable toe two like its dromaeosaur relations, but also had the reversed, or partially reversed, toe one like modern perching birds. This most likely indicates that it was a generalist, capable of ground or arboreal movement. Although it is not known whether Archaeopteryx is the direct ancestor of modern birds, it is clear that birds, and flight, were evolving at this time. Typically avian foot features are found in the fossil record shortly after Archaeopteryx, and characteristics of flight, such as the wing, show rapid change whereas those of the skeleton and skull evolved more slowly. URLs: code http://www.dinosauria.com/jdp/archie/solnhof.htm [|http://web.ebscohost.com.ez.sccd.ctc.edu:3048/ehost/detail?vid=1&hid=13&sid=f6d35c19-3f00-4a7a-b470-58ebf02d9d26%40] [|sessionmgr9] http://www.dinosauria.com/jdp/archie/archie.htm http://journals.cambridge.org http://www.dinosauria.com/jdp/archie/dromey.htm http://web.ebscohost.com.ez.sccd.ctc.edu:3048/ehost/detail?vid=1&hid=9&sid=3cb0cdd8-d511-46a8-baad-02b3227d36df%40sessionmgr9, http://en.wikipedia.org/wiki/Archaeopteryx http://www.thefreedictionary.com/bird
 * 2. Early Birds**

code B. What do we know about the evolution of the early birds, what are some of the discoveries of early birds and who discovered them? - NO ONE URLs: C. What do we know about why birds evolved the way they did, what are the ideas for the origin of flight, how did the birds (avian dinosaurs) survive the big extinction while the (non-avian) dinosaurs did not? -- Wendy The earliest known fossil bird is Archaeopteryx which is from the late Jurassic period. It had a flat sternum and teeth which separate it from modern birds. Like modern birds, it had feathers, hollow bones, and reduced fingers. Birds are an extremely diverse species and therefore it is important to trace the oldest ancestor to eliminate recent modifications when trying to determine their development. The ability to fly allows birds to travel to every part of the globe and allows for hummingbirds, ostridges and penguins in the same species. Current research questions whether the Archaeopteryx was the earliest bird or a cross between a dinosaur and a bird as it had dominant features of both. Another possibility for the oldest bird ancestor is the gansus yumenensis which was recently discovered in China. These were able to fly and swim and possessed feathers but lacked hollow bones.

There are many theories about why wings and therefore flight developed. One of them was the development of defensive strategies such as a quick escape from predators or to free up the hind legs for use as a weapon. This could have resulted in the development of wings to assist in leaping and flying could have been a by product of this. A second but equally likely theory was the need to reach food sources. This could have involved reaching flying or speedy prey or allow access to new and untapped food sources first aided by wings and then flight. A debate is ongoing between the theories of tree to tree “gliding” flying as the first versus flight from the ground up. Either one could have resulting in wings developing by gliding or leaping ancestors flapping their wings to gain thrust. Recent research has happened recently to show the likelihood of both theories but neither can yet be proven definitively.

URLs: D. Still to be determined topic -- Ryan URLs:

A. How do we connect the "first bird" and the "early birds" to the feathered dinosaurs? -- Sabrina
 * 3. Transition from Feathered Dinos to Early Birds**

Facts have proven that birds are the descendants of dinosaurs, but how exactly did this happen and how are they linked? Let’s look at connections between the first bird and the feathered dinosaurs.

The first non-avian feathered dinosaurs were found more than a hundred years after the discovery of Archaeopetryx, in the early 1990’s. Most of the non-avian dinosaurs have been discovered in China, but they have also been found in both eastern and western regions of the United States, Europe, North Africa, Asia, South America, Antarctica and Madagascar.

It has been suggested that although Archaeopteryx is believed to be the first bird, that it’s species did not evolve and become the birds of today.

It is now felt that the Aves descended from Coelurosurian Theropods, specifically from a clade called Maniraptora. This group is believed to have appeared in the late Jurassic, and was only named just over 20 years ago, in 1986 by Jacques Gauthier.

It was in the 1960’s that scientist John Ostrum revived the idea of birds being descendants of dinosaurs. Today we know that there are over 100 similarities between birds and Theropod dinosaurs.

It is also believed that Dromaeosaurids and Troodontids form the clade Deinonychosauria, whose members are the sister taxon to birds.

URLs: http://en.wikipedia.org/wiki/Feathered_dinosaurs http://en.wikipedia.org/wiki/Coelurosaur www.enchantedlearning.com/subjects/dinosaurs/dinos/Archaeopteryx.shtml www.ucmp.berkeley.edu/diapsids/birds/birdfr.html www.ucmp.berkeley.edu/diapsids/saurischia/maniraptora.html http://en.wikipedia.org/wiki/Maniraptor http://en.wikipedia.org/wiki/Deinonychus http://en.wikipedia.org/wiki/Dromaeosauridae

B. What do we know about flying dinosaurs (birds) having evolved from a subgroup of the carnivorous non-flying dinosaurs, the theropods -- Melissa Archaeopteryx lithographica, by many is considered to be the first bird. Found in southern Germany in Jurassic strata, its age is estimated to be about 150 million years old. Paleontologists have long accepted that Archaeopteryx was a transitional form between birds and reptiles. Some scientist believe that it resembles its ancestors, the Maniraptora, then its modern bird relatives. Maniraptora are a group of theropod (bipedal) dinosaurs that many paleontologists concluded where birds first derived from in the Jurassic, about 150 mya. Maniraptoran groups include but are not limited to; Aves (birds), Dromaeosaurs (raptor dinosaurs), Troodontids (smallest non-avian dinosaurs), Therizinosaurs (plant-eating theropods), and Oviraptors (maniratorans with strange evidence of devoted parental care). Maniraptorans are united by the possession of modified elements in the wrist; the semilunate carpel bone unique to this group. Other modifications include to the forelimb (which makes fight possible for birds), fused clavicle, and sternum. In the fossil record, Archaeopteryx has clear feather impressions around the body. There is open debate to whether these feathers were used for flight or regulating body temperature. Also still open to debate is Archaeopteryx ability to fly. Two models of the evolution of flight are proposed: the “tree-down” model, birds evolved from ancestors that lived in trees and could glide from tree to tree. And “ground-up” model, the ancestors of birds lived on the ground and made long leaps. The ancestry of birds starts in the theropod dinosaur family tree. The figure of the family tree I have adapted from the work that was put together by Prof. Kevin Padian, starting in the late Trassic (Theropoda; Coelophyisis) and ending with the middle Cretaceous (Aves; Archaeopteryx) to now (Neornithes; living birds). The cladogram figure on next page:
 * The Origin of Birds**




 * Empty spots indicate gaps in the fossil record. Blue words indicate evolutionary novelties.**

URLs: An early bird- http://www.ucmp.berkeley.edu/diapsids/birds/archaeopteryx.html

Family tree- http://www.geocities.com/CapeCanaveral/Hall/2099/jj2ftree.html http://www.geocities.com/CapeCanaveral/Hall/2099/DinoKabin.html

Are birds really Dino?- http://www.ucmp.berkeley.edu/diapsids/avians.html

Mayor Groups of Coelurosaurs- http://www.ucmp.berkeley.edu/diapsids/saurischia/coelurosauria.html

Dromaeosauridae- http://www.ucmp.berkeley.edu/diapsids/saurischia/dromaeosauridae.html


 * Bibliography**

"Archaeopteryx : An Early Bird." University of California Museum of Paleontology. 1997. 1 Feb. 2008 <[|http://www.ucmp.berkeley.edu/diapsids/birds/archaeopteryx.html>.] (Melissa)

"Archaeopteryx." Enchanted Learning. 1 Feb. 2008 <[|www.enchantedlearning.com/subjects/dinosaurs/dinos/Archaeopteryx.shtml]>. (Sabrina)

"Archaeopteryx." Wikipedia. 16 Feb. 2008. 16 Feb. 2008 <[|http://en.wikipedia.org/wiki/Archaeopteryx>.] (Carrie)

"Are Birds Really Dinosaurs?." University of California Museum of Paleontology. 22 Jan. 1998. 17 Feb. 2008 <[|http://www.ucmp.berkeley.edu/diapsids/avians.html>.] (Melissa)

"Aves:Fossil Record." University of California Museum of Paleontology. 11 Jan. 1996. 1 Feb. 2008 <[|www.ucmp.berkeley.edu/diapsids/birds/birdfr.html]>. (Sabrina)

"Birds Arrived Comparatively Late." The Life of Birds PBS. http://www.pbs.org/lifeofbirds/evolution/index.html

"Bird." The Free Dictionary. 2008. 17 Feb. 2008 <[|http://www.thefreedictionary.com/bird>.] (Carrie)

"Coelurosaur." Wikipedia. 16 Feb. 2008. 16 Feb. 2008 <[|http://en.wikipedia.org/wiki/Coelurosaur>.] (Sabrina)

"Deinonychus." Wikipedia. 16 Feb. 2008. 16 Feb. 2008 <[|http://en.wikipedia.org/wiki/Deinonychus>.] (Sabrina)

"DinoKabin." The kabinet of 'doktor' Strangetruther. 1 Feb. 2008 <[|http://www.geocities.com/CapeCanaveral/Hall/2099/DinoKabin.html>.] (Melissa)

"The Dromaeosauridae." University of California Museum of Paleontology. 24 Nov. 1995. 1 Feb. 2008 <[|http://www.ucmp.berkeley.edu/diapsids/saurischia/dromaeosauridae.html>.] (Melissa)

"Dromaeosauridae." Wikipedia. 16 Feb. 2008. 16 Feb. 2008 <[|http://en.wikipedia.org/wiki/Dromaeosauridae>.] (Sabrina)

"Evolution of Flight." University of California Museum of Paleontology. 11 Jan. 1996 http://www.ucmp.berkeley.edu/vertebrates/flight/evolve.html

"Fabulous Fossil Strengthens Dino-Bird Link." Current Science 87.1 (2001): 12-13. Education Module. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=12&did=78904776&SrchMode=1&sid=1&Fmt=3&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202240237&clientId=79571. (Brian)

Family tree- " JJ2F tree." The kabinet of 'doktor' Strangetruther. 20 Mar. 2003. 1 Feb. 2008 <[|http://www.geocities.com/CapeCanaveral/Hall/2099/jj2ftree.html>.] (Melissa)

"’Feathered’ Dinosaurs." Dann's Dinosaurs. 1 Feb. 2008 . (Niel)

"Feathered Dinosaurs." Wikipedia. 16 Feb. 2008. 16 Feb. 2008 <[|http://en.wikipedia.org/wiki/Feathered_dinosaurs>.] (Sabrina)

Friesen, Stan. "Archaeopteryx and the Solnhofen Lagoon." Dinosaur Mailing List. 1995. 1 Feb. 2008 <[|http://www.dinosauria.com/jdp/archie/solnhof.htm>.] (Carrie)

Hecht, Jeff. "How dinosaurs were able to grow so big." __New scientist__ 188.2523 (2005): 14. __Academic Search Premiere__. EBSCO. North Seattle Community College. 15 Jan. 2008 . (Carrie)

Holtz, Thomas. "Archaeopteryx's Relationship With Modern Birds." Dinosaur Mailing List. 1995. 1 Feb. 2008 <[|http://www.dinosauria.com/jdp/archie/archie.htm>.] (Carrie)

"The Major Groups of Coelurosaurs." University of California Museum of Paleontology. 11 Nov. 1995. 1 Feb. 2008 <[|http://www.ucmp.berkeley.edu/diapsids/saurischia/coelurosauria.html>.] (Melissa)

"Maniraptor." Wikipedia. 16 Feb. 2008. 16 Feb. 2008 <[|http://en.wikipedia.org/wiki/Maniraptor>.] (Sabrina)

"Maniraptora ("Seizing Hands")." University of California Museum of Paleontology. 24 Nov. 1995. 1 Feb. 2008 <[|www.ucmp.berkeley.edu/diapsids/saurischia/maniraptora.html]>. (Sabrina)

Mayr, Gerald, Burkard Pohl, and D Stefan Peters. "A Well-Preserved Archaeopteryx Specimen with Theropod Features." Science 310.5753 (2005): 1483-86. Research Library Core. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=1&did=942798921&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202237440&clientId=79571. (Brian)

Norell, Mark A., and Xing Xu. "Feathered Dinosaurs." Annual Review of Earth and Planetary Science 33 (2005): 277-99. Platinum Full Text Periodicals. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=3&did=857758811&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202237440&clientId=79571. (Brian)

Padian, K, and L Chiappe. "The origin and early evolution of birds." __Biological Reviews__ 1998: 1-42. 25 Jan. 2008 <[|http://journals.cambridge.org>.] (Carrie)

Paul, Gregory S. "Dromaeosaurid Archaeopteryx." Dinosaur Mailing List. 1996. 1 Feb. 2008 <[|http://www.dinosauria.com/jdp/archie/dromey.htm>.] (Carrie)

Poling, Jeff. "Feathers, Scutes and the Origin of Birds." [|Dinosauria.com]. 18 Nov. 1996. 10 Feb. 2008 http://www.dinosauria.com/jdp/archie/scutes.htm. (Brian)

Xu, Xing. "Feathered Dinosaurs from China and the Evolution of Major Avian Characters." Integrative Zoology 1.1 (2006): 4-11. Google. Blackwell Synergy. 4 Feb. 2008 http://www.blackwell-synergy.com/doi/pdf/10.1111/j.1749-4877.2006.00004.x?cookieSet=1. (Brian)

Xu, Xing. "Palaeontology: Scales, Feathers and Dinosaurs." Nature 440.7082 (2006): 287-288. Research Library Core. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=0&did=1013273891&SrchMode=1&sid=2&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202237440&clientId=79571. (Brian)

Xu, Xing, M.A Norell, Xuewen Kuang, Qi Zhao, Chengkai Jia and Xiaolin Wang. "Basal tyrannosauroids from China and evidence for protofeathers in tyrannosauroids." Nature 431 (2004): 680-684. (Niel)

Xu, Xing, Zhong-he Zhou, and Richard O. Prum. "Branched Integumental Structures in Sinornithosaurus and the Origin of Feathers." Nature 410.6825 (2002): 200-04. Research Libary Core. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=13&did=69920404&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202240237&clientId=79571. (Brian)

Yu, Mingke, Ping Wu, Randall B. Widelitz, and Cheng-Ming Chuong. "The Morphogenesis of Feathers." Nature 420.6913 (2002): 308-12. Research Libary Core. ProQuest. North Seattle Community College, Seattle, WA. 6 Feb. 2008 http://proquest.umi.com.ez.sccd.ctc.edu:3048/pqdweb?index=10&did=245919421&SrchMode=1&sid=1&Fmt=6&VInst=PROD&VType=PQD&RQT=309&VName=PQD&TS=1202240237&clientId=79571. (Brian)