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Bird Evolution Not Indisputable as Evolutionists Claim



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4. Bird Evolution Not Indisputable as Evolutionists Claim

One of the biggest controversies in evolution today is that birds evolved from dinosaurs, and that proof of this can be found in the fossil record. The famous Archaeopteryx fossil, supposedly a transitional species between lizards and full-fledged, anatomically modern birds, forms the linchpin of the dino-to-bird evolutionary theory. However, George E. Watson, Curator of Birds at the Smithsonian Institution, called attention to the problems with this creature:

Not until the late Cretaceous, some 50 million years after Archaeopteryx, do birds appear in the fossil record in North America. The gap seems illogical. The sudden burst of a diverse bird life, including some species remarkably close to modern families, implies the presence of earlier, more primitive birds, but they left no fossil trace (1976: 101 [emphasis added]).

Commenting on the alleged transition from lizards to birds, Watson admitted: “A scant fossil record tells little of how these adaptive changes came about...” (1976: 102). Famed paleontologist John Ostrom of Yale University summed up the problem with believing that birds evolved from dinosaurs: “We don’t have the evidence to support any kind of direct lineal descent. There are too many gaps in the fossil record. We’re in the business of connecting dots scattered in time and space” (Ackerman 1998: 92). Mark Norell, chairman of the department of vertebrate paleontology at the American Museum of Natural History in New York, similarly commented: “You could take all the fossils ever collected relevant to this debate and fit them nicely in my office” (Ackerman 1998: 95).

Philip Currie, curator of the Royal Tyrell Museum in Canada, remarked that “one of the problems there has been for a long time in dealing with the Cretaceous bird record is that most of it is ambiguous” (Chandler 1998: A21). As for Archaeopteryx, Jennifer Ackerman of the Bunting Institute at Radcliff commented: “More than a hundred years after the discovery of Archaeopteryx, scientists still aren’t sure how well it could fly. Nor is it clear how its ancestors first took wing” (1998: 98). The March 14, 2003 issue of the journal Science likewise stated that “Archaeopteryx’s lifestyle and its importance to the origins of avian flight remain disputed topics” (Livezey 2003: 1664). Richard O. Prum, associate professor of ecology and evolutionary biology and curator of ornithology at the History Museum and Biodiversity Research Center at the University of Kansas, and Alan H. Brush, professor emeritus of ecology and evolutionary biology at the University of Connecticut, have noted:

For many years the earliest bird fossil has been Archaeopteryx lithographica, which lived in the late Jurassic period (about 148 million years ago). But Archaeopteryx offers no new insights on how feathers evolved, because its own feathers are nearly indistinguishable from those of today’s birds (2003: 86).

Ann Burke, a biologist at the University of North Carolina, and her colleague, Alan Feduccia, an expert on bird evolution, have come out against the idea that birds evolved from dinosaurian ancestors. Writing in the journal Science, Feduccia gave two chief reasons why the alleged “milestone” of dinosaurs evolving into birds is erroneous. First, he pointed out that the earliest birdlike dinosaurs appear in the fossil record millions of years after the appearance of the first known birds. “Second,” he wrote, “flesh-eating dinosaurs thought to have given rise to birds were large, earthbound creatures with heavy balancing tails and short forelimbs. This is absolutely the worst body plan for the evolution of bird flight” (Anonymous 1997: A3).

In 2001, the journal Science News published an article on the discovery of “dinofuzz” that has been touted as evidence for dinosaur-to-bird evolution. The article began by mentioning the famous Archaeopteryx, stating that it was “[t]he oldest known bird” and that it “had modern feathers” (Wang 2001: 149). The first problem is that these fully formed, modern feathers appear suddenly in the fossil record, with no evidence of eons of evolution having produced them. “To have an incredibly new and complex thing [like feathers] suddenly arise with no known antecedents is tough to explain,” said Prum (Wang 2001: 149).

To try and account for this, Prum and colleagues from China’s Institute of Vertebrate Paleontology and Paleoanthropology made the claim that a fossil of the dinosaur Sinornithosaurus millennii (“Chinese bird lizard of the millennium”) showed signs of rudimentary feathers, thus providing evidence that Archaeopteryx’s full-blown, modern feathers do indeed have primitive predecessors. However, as Science News pointed out, “the Sinornithosaurus fossil is younger than that of Archaeopteryx,” since the former is supposedly 124 million years old, while the latter is alleged to be 150 million years old (Wang 2001: 149). That being the case, Archaeopteryx’s feathers could hardly have evolved out of proto-feathers that did not appear (according to old-earth dating assumptions) until 26 million years later.

Ornithologist Storrs L. Olson of the National Museum of Natural History in Washington, DC, agreed, pointing out that this is true for other alleged examples of proto-feathers on dinosaurs: “All these so-called feathered dinosaurs are younger than the first real known birds” (Wang 2001: 149 [emphasis added]).

But that isn’t the only problem with discoveries of this kind. The allegedly feather-like filaments that Prum and his colleagues saw imprinted in the Sinornithosaurus fossil are exactly that-filaments. Moreover, they are not even the filaments themselves, but fossilized impressions of them, so no direct analysis can be made. This “dinofuzz” is simply too vague to be held up as solid evidence for dinosaur-to-bird evolution, as Science News pointed out:

In recent years, researchers have unearthed dinosaur remains that appear to be covered in a layer of ‘dinofuzz,’ notes Lawrence Witmer, a paleontologist at Ohio University in Athens. But these wispy hairlike structures are so unlike modern feathers that skeptics have all but dismissed the possibility that the two could be related (Wang 2001: 149).

Even Prof. Witmer, who leans toward the belief that dinofuzz is a form of proto-feather, himself admitted, “We’re looking at stuff strewn about on a rock, and consequently a lot of it is open to interpretation” (Wang 2001: 149). Dr. Olson noted that those who interpret dinofuzz as evidence for bird evolution do so because they have already reached pre-determined conclusions: “They want to see feathers…so they see feathers. This is simply an exercise in wishful thinking” (Wang 2001: 149).

So, even leading evolutionists have admitted that the “evidence” for dinosaur-to-bird evolution is unhelpful. First, alleged proto-feathers (“dinofuzz”) are more recent than fully developed, modern feathers, negating the possibility that dinofuzz is an evolutionary step toward true feathers. Second, dinofuzz itself is too vague and too widely open to interpretation to be held up as incontrovertible evidence for bird evolution. Those who claim that it is are basing their conclusions on their own pre-determined theories, not on hard science.


References:

Ackerman, J. 1998. “Dinosaurs Take Wing.” National Geographic 194, no. 1.

Anonymous. 1997. “Dinosaur-bird connection is found to be unlikely.” Boston Globe, 24 October.

Chandler, D.L. 1998. “Fossil indicates parrots lived in the dinosaur era, a report asserts.” Boston Globe, 5 November.

Livezey, B.C. 2003. “Millennial Status Report as Debate Wanes.” Science 299, no. 5613.

Prum, R.O., and A.H. Brush. 2003. “Which Came First, the Feather or the Bird?” Scientific American 288, no. 3.

Wang, L. 2001. “Dinosaur fossil yields feathery structures.” Science News 159, no. 10.

Watson, G.E. 1976. “…And Birds Took Wing.” In Our Continent, E.H. Colbert, ed. Washington, DC: The National Geographic Society.




5. Whale Evolution?
In the 1980s and 1990s, numerous fossils were found, particularly in Pakistan, which allegedly demonstrated that whales evolved from land-dwelling, carnivorous mammals called mesonychids. A slew of fossils seemed to indicate an unmistakable progression from the land-dwelling Pakicetus (“Pakistan whale”) all the way up to modern whales in a traditionally Darwinian step-by-step manner. It turns out, however, that paleontologists were seeing in these fossils what they wanted to see, rather than what actually was there.

While these fossils were being unearthed, geneticists in the US, Belgium, and Japan analyzed the DNA of living whales and determined that the mesonychid-to-whale progression, supposedly so obvious in the fossil record, was false. These tests suggested that whales did not descend from mesonychids at all, but are members of a mammal family called the artiodactyls, which include hippopotami. At first, whale paleontologists firmly dismissed the findings. However, more meticulous DNA testing led by Norihiro Okada at the Tokyo Institute of Technology strengthened the findings considerably, and paleontologists dropped their objections (Wong 2002: 78).

Later, excavations in Pakistan turned up foot bones of Pakicetus and another alleged ancestor of today’s whales, Ichthyolestes, and the mesonychid theory was finally dropped, despite what had appeared to be overwhelming fossil evidence in its favor. The reason was that all members of the artiodactyl family have a unique feature in their anklebones known as a “double-pulleyed astragalus.” The anklebones of both Pakicetus and Ichthyolestes were found to have this unique feature, identifying them as members of the artiodactyl family, not as mesonychids (Wong 2002: 78-9).

Scientific American reported that the mesonychid theory soon went the way of countless other evolutionary theories that were once touted as practically undeniable:

What of the evidence that seemed to tie early whales to mesonychids? In light of the new ankle data, most workers now suspect that those similarities [between mesonychids and whales] probably reflect convergent evolution rather than shared ancestry and that mesonychids represent an evolutionary dead end (Wong 2002: 79).

Two points must be raised here. First, the similarities between mesonychids and early whales do not automatically have to be interpreted as “convergent evolution,” but could just as well be credited to Intelligent Design. Second, evolutionists are now falling into the same trap that they fell into with their mesonychid theory: the fact that two extinct creatures, Pakicetus and Ichthyolestes, were highly similar to whales does not necessarily mean that they are the evolutionary ancestors of whales, but merely that they were related to them.

Although scholars of whale origins still cling to the theory of macroevolution (major changes leading to brand-new species), the failure of the mesonychid theory displays the extreme danger of using fossils to determine evolutionary ancestry. For 20 years, the findings in Pakistan and other places were touted as solid evidence for the evolution of whales from mesonychids, but later finds proved them wrong. This accentuates the essentially unreliable nature of trying to use the fossil record as proof of macroevolution, and it also shows how paleontologists convince themselves to see what they want to see in the fossil record, rather than what is actually there.
Reference:

Wong, K. 2002. “The Mammals that Conquered the Seas.” Scientific American 286, no. 5.




6. Do Genetic Studies Demonstrate Evolution?
Media reports claim that genetic studies of animals and humans demonstrate that groups of related species stem from a common evolutionary ancestor. This appears to provide solid evidence for evolution, far beyond a few fossil fragments that can be easily misinterpreted (as we’ve seen in the case of whales). An example of the confidence in genetics can be found in a statement by evolutionist Carl Zimmer in National Geographic:

From generation to generation certain genes of a species mutate at relatively steady rates. If you compare the genes of two species, say humans and chimpanzees-and you know the rates at which their genes have been mutating-you can estimate how long it has been since their ancestors diverged from a common ancestor (2001a: 94).

However, claims that geneticists have “seen” proof of evolutionary divergence in the distant past are misleading. In truth, the allegedly visible evidence in the genetic record is not incontrovertible fact but inference based on assumptions. For example, Jonathan Losos, professor of biology at Washington University and director of that school’s Tyson Research Center, writes:

By comparing DNA sequences for the same gene or genes in different species, biologists can draw inferences about how species are related evolutionarily. Although controversy exists about the best method of deducing phylogenetic relationships from DNA comparisons, researchers agree that species that have more similar DNA are, in most cases, more closely related to each other than to another species whose DNA is less similar (2001: 66 [emphasis added]).

Zimmer himself, despite his earlier statement, has also shown that genetic mapping only provides inference for, not proof of, evolution. Instead of showing a clear map of how a given species evolved from a lower life-form, the genetic record shows a gigantic amount of genetic mutations that neither harm nor improve the species (called “neutral evolution”). Zimmer reports: “The irony [of this discovery] was inescapable: scientists finally had a chance to tune in to evolution on its most basic level, but the signal of natural selection seemed to be swamped by the static of neutral evolution” (2001b: 16).

Worse, the signs of evolution by natural selection, supposedly visible in the genetic record, are simply not there, so inferences have to be made, as Zimmer admits:

[R]esearchers can’t go back millions of years to read a gene’s ancestral sequence, nor can they know the precise history of mutations that led up to its current form. But biologists can make some inferences by comparing the genes of closely related animals….But the evidence from real genes is rarely so clean, and thus some uncertainty inevitably creeps in (2001b: 18 [emphasis added]).

In an attempt to detect natural selection, Zihen Yang of University College London programmed computers to look at every possible mutation that genes could have made over the eons. Zimmer, however, points out the basic flaw in this system:

…Yang examines each site in a gene and tries to predict its nucleotide on the basis of the rest of the gene’s sequence as well as the sequence of the gene in related species. The computer makes a series of predictions based on different assumptions about the level of natural selection acting on the site and then picks the level that works best (2001b: 19 [emphasis added]).

Thus, the science of genetics is no better at providing rock-solid proof of evolution than fossils. As with the fossil record, the genetic record does not unquestionably show species Y and Z evolving out of species X. Instead-again like the fossils-the genetic “evidence” is only speculation based on inference and pre-determined assumptions employed to reach a conclusion that evolutionists have already decided they’re going to reach.


References:

Losos, J.B. 2001. “Evolution: A Lizard’s Tale.” Scientific American 284, no. 3.

Zimmer, C. 2001a. “How Old Is It?” National Geographic 200, no. 3.

Zimmer, C. 2001b. “Tuning In.” Natural History 110, no. 7.




7. Microevolution within a Species - Yes; Macroevolution between Species - No
Evolutionists claim that animals, when continually exposed to negative situations or attacks, evolve defense mechanisms to overcome these assaults. A common example is parasitism: Darwinists argue that, over the eons, animals that habitually fall victim to parasites evolve into creatures with better defense mechanisms, while parasites evolve improved methods to parasitize their evolving hosts. This thinking can be found in the journal Natural History, which claimed that a host’s

immune system, an exquisitely precise system of defense brought about by the evolutionary pressure of parasites, will do its level best to stave off the invasion. But host organisms have evolved other kinds of warfare as well: they can enlist other species to help them; they can medicate themselves; they can even program their unborn offspring for life in a parasite-ridden world (Zimmer 2000: 47)….As effective as some of these counterattacks may seem, parasites-not surprisingly-can evolve counter-counterattacks (Ibid. 49).

The problem with this theory is that no scientist has ever seen a host animal develop a new defense mechanism that caused it to evolve into a brand-new, higher life-form; similarly, no one has ever witnessed a parasite develop a new, improved attack method that ultimately resulted in its transformation into a new species. If this occurred, it would be “transpecific macroevolution”-the development of lower life-forms into new, more highly-developed species. What scientists have actually seen is “intraspecific microevolution”-small changes within a single species in response to external factors, giving the animal an increased ability to deal with these factors but not creating a new, higher life-form.

Experimentation on fruit flies has proved this, while no proof has ever been shown for macroevolution into new species. A.R. Kraaijveld of Britain’s Imperial College of Science, Technology and Medicine conducted an experiment in which he permitted parasitic wasps to attack a number of fruit flies from one species. The attack resulted in the deaths of 19 out of 20 host flies. Kraaijveld then bred the survivors among each other. The next generation was attacked, and Kraaijveld bred those survivors, etc. The attacking wasps were kept separate from the flies (Kraaijveld allowed them to live off another fly species in a separate container) to preclude the possibility that the wasps were evolving along with the victimized flies. Within five generations, the resistance rate of parasitized flies increased from 1 in 20 to 12 in 20-that is, from 5% to 60% (Zimmer 2000: 49-50).

Darwinists argue that, given enough time, with the wasps constantly attacking them, the flies would eventually evolve into a new, superior species. Not so, Kraaijveld showed. Natural History reported that

in later generations, the resistance remained at 60 percent. Why didn’t it rise to 100 percent, creating a race of perfectly immune flies? Well, fighting wasps is costly. Kraaijveld set wasp-resistant flies in competition for food against regular flies and found that they fared badly. They grew more slowly, died young more often, and, if they survived to adulthood, were smaller. Evolution doesn’t have an infinite arsenal to offer host organisms, and energy spent on one thing is not available for something else (Zimmer 2000: 50).

The “evolution” witnessed by Kraaijveld is clearly microevolution within a single species. As useful as this mechanism is, it is undeniably limited-it does not create a new, more highly-evolved species, and it doesn’t even create a 100% wasp-resistant fruit fly. Worse, it produces smaller, weaker, shorter-lived creatures, rather than more robust individuals on their way to becoming a new, improved species. Microevolution within a single species is a scientifically proven fact; macroevolution from a lower species into a higher one is sheer speculation, and is disproved by Kraaijveld’s experiments, which demonstrated conclusively that small adaptations are strictly limited to less-than-complete improvements within a life-form.
Reference:

Zimmer, C. 2000. “Attack and Counterattack: The Never-Ending Story of Hosts and Parasites.” Natural History 109, no. 7.




8. Further Evidence for the Cost of Microevolution
The disadvantages possessed by the micro-evolved fruit flies mentioned in the previous section are called “fitness costs” (Read & Allen 2000: 1104). This term refers to the fact that creatures undergoing minor improvements to increase their chances of survival (like building up immunity to parasites) do not macro-evolve into higher species, but actually have to sacrifice part of their vitality to make up for the improvements. In other words, animals only have a limited “budget” for improvement-if they “increase spending” on fighting parasites, they must “decrease spending” on strength, size, lifespan, etc.

Experimentation has demonstrated that what is true for fruit flies holds true for other animals as well as for humans. The journal Science reported: “In taxa [major animal groups] as diverse as snails, moths, mosquitoes, and fruit flies, artificial selection in the laboratory for increased ability to resist parasite attack has been associated with reductions in at least some components of fitness.” The intentional breeding of bumblebees to fend off internal parasites “dramatically reduced their survival compared to bees that were not immunologically challenged.” An attempt to increase wild birds’ immunity to tetanus and diphtheria gave the following result: “Immunized birds fledged [became the parents of] fewer and lighter offspring than non-immunized birds” (Read & Allen 2000: 1104).

These “fitness costs” also occur when humans build up resistance to parasites. In Africa, where malaria is prevalent, local populations have, over time and through random genetic mutations, developed an increased resistance to Plasmodium vivax, the mosquito-borne parasite that causes malaria. This increased resistance, so necessary to survive in Africa, comes with a price; the Harvard Gazette reported that the mutation that increases resistance to malaria “causes sickle cell anemia, a painful inherited blood disease that occurs mainly in blacks. Sickle cell anemia, however, is not usually fatal” (Cromie 2001: 4). Thus, the improvement Africans undergo to fight a lethal disease (malaria) is offset by a painful, debilitating, but not fatal disease (sickle cell anemia). This is a perfect example of how minor improvements within the boundaries of a single species demand a “fitness cost,” rather than serving as a rung on an alleged ladder that leads to a new, higher species.

The conclusion is this: intraspecific microevolution (small physiological changes that occur within a species in order to protect that species from biological attacks) is scientifically proven. However, transpecific macroevolution (the transformation of this micro-mutating species into a completely new creature) is devoid of scientific proof. Micro-mutating species do not keep mutating until they transform into higher life-forms; instead, they sacrifice part of themselves, ultimately resulting in the same species all along.


References:

Cromie, William J. 2001. “Evolution at work: The tale of a tail.” Harvard University Gazette, 8 February.

Read, A.F., and J.E. Allen. 2000. “The Economics of Immunity.” Science 290, no. 5495.

Zimmer, C. 2000. “Attack and Counterattack: The Never-Ending Story of Hosts and Parasites.” Natural History 109, no. 7.




9. Still More Evidence for the Cost of Microevolution
Fitness costs have even been observed in single-celled organisms. A team of French biologists cloned E. coli bacteria that had been modified to possess “mutator alleles” (gene sequences that increase the likelihood of mutation), and injected those bacteria into the intestines of germ-free mice. Also injected into the mice were wild E. coli that did not possess the increased capacity to mutate. After nine days, the “mutators” (the bacteria with the mutator alleles) outnumbered the wild germs 800 to 1 (Giraud 2001: 2606). This is clear evidence of microevolution at work: mutators have a distinct advantage over normal E. coli, an advantage that “depends on their ability to generate adaptive mutations” to new conditions faced in the new environment of a mouse’s intestine (Giraud 2001: 2607).

This microevolutionary advantage, however, proved temporary. After 14 days, the number of wild E. coli caught up with the number of mutators. The biologists observed, “Once the most beneficial adaptive mutations have been generated, the advantage conferred by the mutator phenotype seems to have disappeared” (Giraud 2001: 2607). Even worse for the theory of macroevolution, the scientists declared “that, in addition to rare adaptive mutations, mutator bacteria rapidly accumulate numerous detrimental mutations” (Giraud 2001: 2607).

As it turns out, mutators accumulate mutations that cause them to lose robustness in the mouse’s gut, and these mutations actually turn into disadvantages in the natural world. To confirm this, the researchers allowed germ-free mice to mingle freely with mice infected with mutators and with mice infected with wild E. coli. The results of the experiment showed that the wild E. coli were more efficient at colonizing the germ-free mice than were the mutators (Giraud 2001: 2608).

The biologists concluded, “The mouse model showed that the advantage of mutator bacteria when colonizing [a] new host [a mouse with bacteria in its gut] is due to their capacity to generate adaptive mutations rapidly, allowing them to exploit the ecosystem resources more quickly than wild-type bacteria. This advantage is reduced to little or nothing once adaptation is achieved. Moreover, if the mutation rate is not reduced…it leads progressively to loss of functions that are dispensable in the current environment but compromise the long-term survival of mutator clones. Our experiments also showed that bacterial migration between hosts is a potent factor in reducing the benefits of enhanced mutation rate…” (Giraud 2001: 2608 [emphasis added]).

Once again, experimentation has shown that microevolution 1) does not produce a new species, and 2) carries a cost, because the microevolving creature becomes disadvantaged in one area despite having become advantaged in another. The case of E. coli is exactly like the fruit flies, bumblebees, birds, and human beings discussed earlier. Minor changes within species simply do not produce new species.
Reference:

Giraud, Antoine, et al. 2001. “Costs and Benefits of High Mutation Rates: Adaptive Evolution of Bacteria in the Mouse Gut.” Science 291, no. 5513.





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