How Evolutionists Come Up With The New Bat Hypothesis

Scientists are trying to answer a question, “How did bats evolve into the only flying mammal?”  Their conclusion, evolution provided the bats with higher level of energy because flying requires a lot of energy to accomplish. So they compared other genes of other animals with bats and came up with some stats. Mitochondrial genes and nuclear genes of the two bats whose draft genomes were published. Then compared genes for metabolism and came up with 25 percent was a “signature” for positive selection

Scientists admitted that trying to find a “signature” for positive selection is tricky business…

Typically, positive selection will act on only a few sites and for a short period of evolutionary time; thus the signal for positive selection usually is swamped by the continuous negative selection that occurs on most sites in a gene sequence.”

“Even after a short period of positive selection, this is commonly followed by a long period of purifying selection, which would obscure the selective processes. These processes explain why it has been so difficult to detect positive selection in mtDNA, despite extensive studies.”

A rescue hypothesis is evoked in this paper on why there is no physical proof for positive selection. Austin L. Hughes, an evolutionary biologist at the University of South Carolina dropped a bombshell on how this data is collected and presented…”In recent years the literature of evolutionary biology has been glutted with extravagant claims of positive selection on the basis of computational analyses alone, including both codon-based methods and other questionable methods such as the McDonald-Kreitman test.  This vast outpouring of pseudo-Darwinian hype has been genuinely harmful to the credibility of evolutionary biology as a science.”

Hughes is right on that point when it comes to empirical science but has faulty ideas of his own on how evolution works. So in this latest attempt at explaining bat flight through evolution uses what? Yep, computer generated branch-site models to weed out other signals (non-physical evidence) in order to support their findings on positive selection. But there is a lot more to this…

“Bats are unique in being the only mammals capable of powered flapping flight.  As in birds, bat flight is a highly energetically expensive form of locomotion.  However, it is also a very efficient mode of transport and assists flyers in feeding and breeding as well as avoidance of predators.  The evolution of flight in bats was a major factor leading to the success of this amazing group of mammals, although the evolution of this ability has required complex changes in the anatomy of these animals.”

“In addition to other important factors, such as changes in bone density and development of the wings, bat flight also requires a significantly higher metabolic rate, a rate well above the maximum capable by other similar-sized terrestrial mammals during exercise.”

“Aerobic metabolism by mitochondria plays a vital role as the energy production centers of cells The OXPHOS pathway of mitochondria has adaptively evolved to meet the demands of changing environmental and physiological conditions.”

“Because the mitochondrial respiratory chain has a dual genetic foundation (mitochondria and nuclear genomes), here we examined both genomes to obtain insights into the evolution of flight by mammals.  Both mitochondrial genes and nuclear-encoded OXPHOS genes showed greater evidence for adaptive evolution; this result supports our hypothesis that energy metabolism genes were targets of natural selection that included a balancing cytonuclear coevolutionary constraint, which allowed adaptive changes in energy demands and thus played a crucial role in attainment of flight by bats.”

Convincing oneself this is evidence for random mutations being selected to create other forms of animals is one thing, it’s quite another to actually prove it. Adding energy for example to a rat will not make it fly nor adding energy to a mouse (which is supposedly bats came from in evolution). Suggesting increases in a step by step slightly higher metabolic rate for an animal is going to produce a flying bat is ridiculous. In the fossil record, bats appear abruptly fully formed already having the ability to fly, no transitions of animals (bats or mice) going from land to flight.

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6 thoughts on “How Evolutionists Come Up With The New Bat Hypothesis

  1. Michael !!!

    You still have not answered our three questions.

    Instead, yet another post.

    Come on, you surely can answer our rather simple questions.

  2. Upson Downes

    Tthe questions are:

    (1) Blog readership numbers in response to Eelco’s February challenge that your readership asymptotically approaches zero’

    (2) Your qualifications to discuss any scientific subject, in response to Olorin’s February accusation of towering ignorance and gynormous falsehoods in your posts.

    (3) A substantive review of Signature in the Cell, promised for August 2009.

    You can run, but you can’t hide.

  3. Michael: “In the fossil record, bats appear abruptly fully formed already having the ability to fly, no transitions of animals (bats or mice) going from land to flight.”

    Yes. And this fact encouraged creationists to sit back and smile smugly in their ignorance. On the other hand, scientists took it as a challenge to perform further research, in order to add to our fund of knowledge.

    And what did they find?

    First of all, the wings. Michael doesn’t marvel here at evolution of the wings. But they were necessary, and they appeared suddenly. A year or so ago, scientists compared the phylogenetic trees of bats and rats. They found a developmental gene that differed. This single gene caused the second and third fingers to grow at an amazing rate—when they modified rats with this gene, the rats’ wing fingers grew at the prodigious rate of 6% per generation! One mutation accounted for the appearance of bat wings in the twinkling of an evolutionary eye.

    Now the wing by itself produces a great selective advantage. Flying squirrels think that their webby wings are enough all by themselves. Proto-bats were gliders, like the squirrels.

    Low bone density helps. This can be a gradual process, because it doesn’t need even a new gene. Only changes in the regulation of a gene. Gradually–in accordance with the dictates of evolution—because each increment is adaptive.

    Now Michael does not believe in natural selection. He does not believe that antelopes become more fleet of foot when lions eat the slow ones. What possible effect could that have? But, for the rest of us, gliding flight provided by the single-gene wings works, but the proto-bats that had mutations for increased metabolism have a further advantage. Metabolism rates are malleable; there are a number of possible pathways to higher or lower rates—even humans exhibit ranges of metabolism—from the peaks of the Olympic sprinter to sedentary specimens such as myself. Therefore, if higher metabolism has reproductive advantages, the alleles that favor it will be selected.

    What the present researchers did was to find the specific mitochondrial and nuclear genes that caused the increased metabolic rates:

    “Both mitochondrial and nuclear-encoded OXPHOS genes display evidence of adaptive evolution along the common ancestral branch of bats, supporting our hypothesis that genes involved in energy metabolism were targets of natural selection and allowed adaptation to the huge change in energy demand that were required during the origin of flight.”

    Michael thinks this is an unsupported conclusion. He merely refuses to read about the experimental evidence:

    “Evidence for positive selection was detected in 23.08% of the mitochondrial-encoded and 4.90% of nuclear-encoded oxidative phosphorylation (OXPHOS) genes, but in only 2.25% of the nuclear-encoded nonrespiratory genes that function in mitochondria or 1.005% of other nuclear genes in bats. To address the caveat that the two available bat genomes are of only draft quality, we resequenced 77 OXPHOS genes from four species of bats. The analysis of the resequenced gene data are in agreement with our conclusion that a significantly higher proportion of genes involved in energy metabolism, compared with background genes, show evidence of adaptive evolution specific on the common ancestral bat lineage.”

    Michael dismisses this evidence as mere storytelling. Michael, please offer your analysis of this evidence’; tell us what in particular is deficient about it.

    .

    But Michael swallows creationist assumptions whole.

    The speed of light suddenly changed by a factor of 10^5 in order to compress the universe into a biblical time frame? No problem. Present rock sedimentary rates have changed by a factor of millions to accommodate the Noachian flood? No problem. Animals underwent millions of years of evolution from herbivorous teeth, walking gaits, grazing behavioral traits to a life of hunting and eating other animals in a matter of days after the Fall? No problem. Bacteria and viruses acquired all their toxic powers in an instant? No problem.

    Now those are fairy tales.

    .

    It is too funny that Michael touts yet another piece of the bat evolution puzzle as evidence for creation. Until we remember his motivation. Fear. Michael desperately seeks to prove evolution wrong, yet he remains afraid… afraid that evolution just might be correct. Then what? Then what indeed.

    This is why creationists cling to ignorance, while scientists search for knowledge. Let’s put it to the test: Would you rather have a creationist or a scientist working on a cure for your cancer?

    Even if you are a creationist yourself.

  4. Michael’s anonymous source: “Adding energy for example to a rat will not make it fly nor adding energy to a mouse (which is supposedly bats came from in evolution). Suggesting increases in a step by step slightly higher metabolic rate for an animal is going to produce a flying bat is ridiculous. In the fossil record, bats appear abruptly fully formed already having the ability to fly, no transitions of animals (bats or mice) going from land to flight.”

    See above comment as to bat wing evolution. Apparently Michael’s anonymous source only reads one paper at a time, and never connects multiple papers together. Wings form from rat fingers by a single gene mutation, which has been shown experimentally to grow full-size wings in a matter of only a few years. This paper didn’t mention wings because rapid wing evolution had already been nailed down.

    Of course, Michael could give us a creationist explantion: How does creationism explain bats? Which biblical kind do they belong to? On what day were they created? Please cite specific physical evidence for your answers.

    .

    Reason #64 why people laugh at creationists.

  5. “How Evolutionists Come Up With The New Bat Hypothesis”

    Hey, Anonymous Secret Source. This is not a “new” bat hypothesis. This is another piece of the same one.

    First came the echolocation capability, some years ago. (It employs a “chirp” signal that some fire-control radars had already employed—man beats nature in this case.)

    Then the rapid wing evolution was explained, solving the problem of why there are no intermediate fossils.

    Now we have the solution to the metabolism question.

    Any other aspect of bat evolution that creationists can pick on? We’ll get right on it.

    ==Soc

  6. From the pages of Psychology Today (March 29, 2010comes this essay: “Creationism as a Mental Illness”

    The salient point is expressed in no uncertain terms:

    It’s a question not just of belief but of denial. The phrase ‘in denial’ has become so commonplace it’s hard to still hear its power. In common with the ostrich which, as danger approaches, buries its head in the sand, those who are ‘in denial’ prefer a false but subjective sense of security to a true but objectively scary reality. Denial brings short term, if illusory, comfort..

    Michael may object that Psychology Today is hardly a peer-reviewed journal. Hence its conclusions may lack a certain … rigor. In that case, we here might object to the use of Science Daily, New Scientist, and similar popular rags as authoritative sources on science.

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