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The Marvelous Flight Capabilities of Birds: Why Evolutionists Never Bluff

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“Avian flight,” a new studyexplains, “is one of the remarkable achievements of vertebrate evolution.” Indeed, there is the “complex biotechnical architecture of avian wings,” the “magic structural wing asymmetries” so important for aeroelastic flight control, and the “extremely precise coordination of the complex wing beat motions, together with a perfect flight guidance and control performance.”  Read more

Jerry Coyne's Chapter on the Fossil Record Fails to Show "Why Evolution is True" - Jonathan M. - December 4, 2012 Excerpt: The second of Coyne's examples is the evolution of birds from theropod dinosaurs, and for this he offers a discussion of Archaeopteryx, in addition to other examples of purported transitional fossils (e.g., Sinornithosaurus millenii). Features that have convinced many paleontologists of Archaeopteryx's transitional status with respect to theropod dinosaurs and birds include the fact that it possesses fully developed feathers (including primaries and secondaries) which were arranged on its wings in a manner similar to modern birds, as well as its reptilian features such as a long bony tail, the claws on its forelimbs and hindlimbs, and its teeth. Other fossilized birds, however, have been found to have teeth (e.g., Hesperornis) and, indeed, some modern birds (e.g., the ostrich) possess fingers on their wings. Moreover, an interesting paper appeared in the Journal of Morphology in 2005, challenging the evidence for feathered dinosaurs (Fedducia et al., 2005). The authors conclude that, "Our ?ndings show no evidence for the existence of protofeathers and consequently no evidence in support of the follicular theory of the morphogenesis of the feather. Rather, based on histological studies of the integument of modern reptiles, which show complex patterns of the collagen ?bers of the dermis, we conclude that "protofeathers" are probably the remains of collagenous ?ber "meshworks" that reinforced the dinosaur integument. These "meshworks" of the skin frequently formed aberrant patterns resembling feathers as a consequence of decomposition." The researchers also "examine evidence relating to the most critical character thought to link birds to derived theropods, a tridactyl hand composed of digits 1-2-3." They find that "the evidence supports interpretation of bird wing digit identity as 2,3,4, which appears different from that in theropod dinosaurs." Another paper published in the Journal of Morphology raises a further problem for the evolution of birds from theropod dinosaurs (Quick and Ruben, 2009). The paper reports, "Although crocodilian lung and cardiovascular organs are markedly less specialized than the avian heart and lung air-sac system, all living archosaurs possess four-chambered hearts and heterogeneously vascularized, faveolar lungs. In birds, normal lung function requires extensive, dorsally situated nonvascularized abdominal air-sacs ventilated by an expansive sternum and specially hinged costal ribs. The thin walled and voluminous abdominal air-sacs are supported laterally and caudally to prevent inward (paradoxical) collapse during generation of negative (inhalatory) pressure: the synsacrum, posteriorly directed, laterally open pubes and specialized femoral-thigh complex provide requisite support and largely prevent inhalatory collapse. In comparison, theropod dinosaurs probably lacked similarly enlarged abdominal air-sacs, and skeleto-muscular modifications consistent with their ventilation. In the absence of enlarged, functional abdominal air-sacs, theropods were unlikely to have possessed a specialized bird-like, air-sac lung. The likely absence of bird-like pulmonary function in theropods is inconsistent with suggestions of cardiovascular anatomy more sophisticated than that of modern crocodilians." Science Daily further explains, It's been known for decades that the femur, or thigh bone in birds is largely fixed and makes birds into "knee runners," unlike virtually all other land animals, the [Oregon State University] experts say. What was just discovered, however, is that it's this fixed position of bird bones and musculature that keeps their air-sac lung from collapsing when the bird inhales. Warm-blooded birds need about 20 times more oxygen than cold-blooded reptiles, and have evolved a unique lung structure that allows for a high rate of gas exchange and high activity level. Their unusual thigh complex is what helps support the lung and prevent its collapse. "This is fundamental to bird physiology," said Devon Quick, an OSU instructor of zoology who completed this work as part of her doctoral studies. "It's really strange that no one realized this before. The position of the thigh bone and muscles in birds is critical to their lung function, which in turn is what gives them enough lung capacity for flight." However, every other animal that has walked on land, the scientists said, has a moveable thigh bone that is involved in their motion -- including humans, elephants, dogs, lizards and -- in the ancient past -- dinosaurs. The implication, the researchers said, is that birds almost certainly did not descend from theropod dinosaurs, such as tyrannosaurus or allosaurus. The findings add to a growing body of evidence in the past two decades that challenge some of the most widely held beliefs about animal evolution. "For one thing, birds are found earlier in the fossil record than the dinosaurs they are supposed to have descended from," Ruben said. "That's a pretty serious problem, and there are other inconsistencies with the bird-from-dinosaur theories." But one of the primary reasons many scientists kept pointing to birds as having descended from dinosaurs was similarities in their lungs," Ruben said. "However, theropod dinosaurs had a moving femur and therefore could not have had a lung that worked like that in birds. Their abdominal air sac, if they had one, would have collapsed. That undercuts a critical piece of supporting evidence for the dinosaur-bird link. Another problem with the claim that birds descended from theropod dinosaurs is that the forelimbs of birds must be able to support their wings and are thus well developed. But the theropods possessed very small forelimbs, which are hardly credible precursors to those of birds and, indeed, a creature like Archaeopteryx. A further difficulty pertains to explaining the origin of feathers. If, as is conventionally maintained, feathers evolved from scales, one has to posit some kind of Darwinian explanation for their evolution from perhaps frayed scales, which must include some kind of genetic basis for every step from frayed scale to fully sculptured feather complete with its many specialized features. Based on what we presently know of the genetic mechanisms, structure and molecular composition of functioning feathers, the proposition that these structures evolved from frayed scales may now reasonably be regarded as highly implausible. Finally, anyone who has carefully followed the scientific discussion on evolution and the fossil record will doubtless be aware that Archaeopteryx has relatively recently been knocked off its perch, as it were, as the first bird, following the discovery of Xiaotingia zhengi in western Liaoning, China, in rocks dating to the late Jurassic epoch, 161-145 million years ago (Xu et al., 2011). As one news report in Nature put it, "we are about to enter a new era in which Archaeopteryx is considered as distant from the ancestry of modern birds as dinosaurs such as Deinonychus." http://www.evolutionnews.org/2012/12/jerry_coynes_c067021.html bornagain77
If not congenitally blind, and 'watching' without seeing. This puts me in mind of the scene in the film autobiography of Ray Charles, where he's sitting in a restaurant with his wife or future wife, I think, and he hears the wings of humming birds in the garden, some way away from where they are seated. Unfortunately, hearing truths they deem undesirable is in no greater favour with Darwin's finest, than seeing with those 'lying eyes'. Axel
It's quite simple. They "arose", they "emerged", they "developed". Atheist miracles all. Seriously, anyone who could watch a hummingbird for thirty seconds and not be convinced of an intelligent Designer must be willfully blind. sagebrush gardener
The Evolution of Birds and Flight: It's impossible Part 1 http://www.youtube.com/watch?v=1yS-r83aw6k melvinvines
OT: Souped-Up Hyper-Drive Flagellum Discovered - December 3, 2012 Excerpt: Get a load of this -- a bacterium that packs a gear-driven, seven-engine, magnetic-guided flagellar bundle that gets 0 to 300 micrometers in one second, ten times faster than E. coli. If you thought the standard bacterial flagellum made the case for intelligent design, wait till you hear the specs on MO-1,,, Harvard's mastermind of flagellum reverse engineering, this paper describes the Ferrari of flagella. " Instead of being a simple helically wound propeller driven by a rotary motor, it is a complex organelle consisting of 7 flagella and 24 fibrils that form a tight bundle enveloped by a glycoprotein sheath.... the flagella of MO-1 must rotate individually, and yet the entire bundle functions as a unit to comprise a motility organelle." To feel the Wow! factor, jump ahead to Figure 6 in the paper. It shows seven engines in one, arranged in a hexagonal array, stylized by the authors in a cross-sectional model that shows them all as gears interacting with 24 smaller gears between them. The flagella rotate one way, and the smaller gears rotate the opposite way to maximize torque while minimizing friction. Download the movie from the Supplemental Information page to see the gears in action. http://www.evolutionnews.org/2012/12/souped-up_flage066921.html bornagain77
Origins - Formed to Fly with Dr. David Menton (dinosaur - bird evolution refuted) - video http://www.youtube.com/watch?v=1eZ7VUgfH2g bornagain77

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