Hypotheses On the Origin of Birds
Since the advent of the theory of evolution the origin of birds has been a thriving topic in science. Many ideas and hypotheses have been presented, but only two stand today: that birds are descendents of ancient thecodont stem reptiles, and that birds are the direct descendents of a group of dinosaurs known as the coelurosaurs. Both hypotheses pose many interesting and insightful ideas based on information obtained from the fossil record. There is not enough evidence at this time to determine which hypothesis, if either, is right. Only more hard work by scientists will tell. Until then we have only speculation, but speculation based in observed evidence.
The origin of birds is one of the great mysteries in biology. Birds are dramatically different from all other living creatures. Feathers, toothless beaks, hollow bones, perching feet, wishbones, deep breastbones, and stump-like tailbones are only part of the combination of features that no other living animal has in common with them (Padian and Chiappe 1998).
Scientists have speculated on the evolutionary history of birds since shortly after Charles Darwin established his theory of evolution in On the Origin of Species (Padian and Chiappe 1998). One year later, in 1860, a solitary fossil feather of a bird was found dating back 150 million years. The next year a skeleton of an animal that had bird-like wings and feathers, but a very unbirdlike long, bony tail and toothed jaw, turned up in the same region. These finds became the first two specimens of Archaeopteryx lithographica, the most archaic known member of the birds, and sparked the immense interest in the evolution of birds and the search for their ancestors (Padian and Chiappe 1998...
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Denotatively a bird is defined as a, Any of a class (Aves) of warm-blooded vertebrates distinguished by having the body more or less completely covered with feathers and the forelimbs modified as wings, often capable of flying. The authors/Glaspell’s strategic comparison of Mrs. Wright to a bird can be interpreted connotatively that she was a free,
Horsey addresses the argument that gay marriage would ruin the sanctity of marriage. The cartoon was made around April, at the same time as Supreme Court rulings on the Defense Of Marriage Act and Proposition 8. By addressing the argument, Horsey is using pathos to allow the reader to make their own conclusion that this claim is incorrect. Rather than stating right out that the claim is incorrect, he proves this to the reader through ironic and comedic imagery and still allows the reader to come to their own conclusion. Horsey places his comic in a 24-hour Las Vegas chapel to prove his point, pointing out a major flaw in the anti-gay argument, which is that not all current heterosexual marriage is sacred. Rather, a large portion of the weddings that take place in Las Vegas are down under the influence of alcohol, not love, like with the intoxicated couple waiting in the window in the cartoon. He also promotes the idea that spontaneous Las V...
Until recently, scientists believed the chances of finding a fossilized dinosaur heart were extremely slim. The heart belonged to a 66 million year old dinosaur found in Harding County in Northwestern South Dakota. The dinosaur, found in 1993, weighed over 650 pounds and was 13 feet long. The dinosaur was in fairly good condition with the exception of the left side of the skeleton. The small, plant-eating Thescelosaurus, nicknamed ‘Willo’ has been acquired by the North Carolina Museum of Natural Sciences. Thescelosaurus was an ornithischian, or "bird-hipped," dinosaur that lived in the latter stage of the Cretaceous period. This was approximately 1 million years before the end of the dinosaur era. Native to North America, its range extended from the northern United States up into Canada. Since using the 3-D software to reveal Willo's heart, scientists have also used it to create 3-D images of the fossil's skull, and of remains from other dinosaurs in the museum's collection. (Fisher, Paul)
There were a few different themes in To Kill a Mockingbird one of which I believe would be the loss of innocence which I believe Dill represents in a odd way. Dill is a childish little boy who likes to play with Jem and Scout in fact early on in the book when the kids were acting Dill “played the character parts formally thrust upon Scout” (jem pg 8). Along with being a good friend and i nice guy Dill only came during the summer and loved to play with the kids he even ran away from home one summer when he couldn't come just to be with them. Dill never really loses his innocence and, I believe because of that he would make a good comparison to the kids at the end of the book after the attack. Along with being a good comparison Dill points out
The Burgess Shale Fauna is a fauna that was constructed based on a group of fossils that were initially found, in the Burgess Shale area in the Canadian Rockies (Gould, 1989). They are a very important group of fossils as “modern multicellular animals make their first unprotected appearance in the fossil record some 570 million years ago” through this group (Gould, 1989, pp. 24). Moreover the Burgess Shales are known to have preserved the soft parts of animals enabling us to get a better understanding of life at the time.
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When architects are put on this earth they have a dream; a dream to change the world in some way, shape, or form. If the architects receive fame and fortunes a result from their work, then that’s just a good perk. The project that they start to work on, integrates numerous elements in order to achieve the set goal. It should also be noted that every space is originally intended for a certain program, regardless of the space being flexible in use. The Paris Opera House professes, via its ceremonious and grand design, its function as a space suited for a gathering place of a “fashionable audience in an era of conspicuous wealth” (Kleiner 811) to enjoy art.
The results of natural selection in Darwin 's finches and British Columbian sparrows change my view of species because every living animal changes to survive conditions that get in the way of normal life.
With its abundance of genera, the Burgess Shale is one of the world’s most important fossil fields. It’s discovery in 1909 led to over 100 years of paleontological study in the Canadian Rockies, a majority of which has been carried out in two quarries known as the Walcott and Raymond quarries (Hagadorn, 2002). Though he was originally in search of trilobites in the Burgess Shale Formation, paleontologist Charles Walcott also discovered a diverse group of soft- and hard-bodied fossils, from algae and sponges to chordates and cirripeds (Hagadorn, 2002). Soft-bodied fossils are incredibly rare due to their delicate structure and susceptibility to decay, so it is hard-bodied fossils that more regularly occur in fossil findings. However over 75,000 soft-bodied specimens have been found in the Burgess Shale formation (Hagadorn, 2002). These specimens are preserved in layers of shale formed from deposits of fine mud. One of the most significant species discovered is the Pikaia gracilens. Believed to be an early chordate, the Pikaia gracilens existed very close to the beginning of the evolutionary path that ultimately lead to humans (McGraw-Hill Encyclopedia, 2006).
...ocietal rules emphasizes the serious consequences of a scandalous. Additionally, Charles Smithson’s relationship with Sarah Woodruff has very notable consequences. Following his admittance to Ernestina, Mr. Freeman files a court order against Charles and specifically means Charles to remain a suitor for the rest of his life. As well, Charles is faced with another consequence following his kiss with Sarah; he feels that it is his duty to pay to put Sarah in a private asylum because of his attachment to her. Furthermore, individuals were faced with consequences after disregarding societal rules associated with sex and marriage.