Molecular evolution is echoed in bat ears


September 5, 2008
Health, Life & Non-humans, Uncategorized

Bats’ ability to echolocate may have evolved more than once, according to research published this week by Queen Mary, University of London scientists.

Species of bat with the ability to echolocate do not all group together in the evolutionary tree of life – some are more related to their non-echolocating cousins, the fruit bats. This has raised the question of whether echolocation in bats has evolved more than once, or whether the fruit bats somehow lost their ability to echolocate.

Writing in the journal Proceedings of the National Academy of Sciences, Dr Stephen Rossiter from Queen Mary’s School of Biological and Chemical Sciences, along with Professor Gareth Jones from the University of Bristol and Professor Shuyi Zhang and Dr Li Gang from East China Normal University in Shanghai, studied a gene called Prestin that codes for a protein of the outer hair cells – the tiny structures in the inner ear that help to give mammals their sensitive hearing (Prestin is linked to deafness in humans).

They looked at the Prestin DNA sequence in a range of echolocating bats and fruit bats and found that parts of the gene appear to have evolved to be similar in the distantly related echolocating species. But they couldn’t find any evidence of genetic changes in the fruit bat Prestin that might be expected from a loss of high frequency hearing.

Dr Rossiter explains: “If Prestin does indeed help bats to hear their high-pitched echoes, then these results appear to support the idea that echolocation has evolved more than once in bats. This apparent independent evolution of a trait in distant relatives is known as convergence, a term that is more commonly used to describe the physical features of species that live in similar habitats and face similar selection pressures, such as the spines of hedgehogs and porcupines.”

Examples of convergence at a molecular level are very rare. Based on their results, Dr Rossiter and his colleagues warn of the potential problems of inferring true evolutionary relationships from genes that may be involved in important functions and, therefore, could be shaped by convergent evolution.

Dr Rossiter added: “If hearing were an Olympic event, echolocating bats would be strong medal contenders. Their ears are tuned to higher sound frequencies than those of any other mammals because they need to listen to the returning echoes of their ultra-sonic squeaks.”



Molecular evolution is echoed in bat ears

3 Responses to Molecular evolution is echoed in bat ears

  1. Anonymous July 2, 2009 at 8:50 pm #

    Typical evolutionist response — “go read this and go read that…”
    They can never explain anything themselves.

  2. Fred Bortz September 5, 2008 at 6:35 pm #

    Josh G.,

    That is a thoroughly discredited argument.

    Here’s a link to my review of book that addresses all your points, most of which fit into the argument known as “irreducible complexity” in the language of Intelligent Design.

    Only a Theory Evolution: and the Battle for America’s Soul by Kenneth R. Miller

    And here’s a link to a list of lots more book reviews that discuss evolution or human origins.

    I suggest you get to a library or a book store and catch up with the latest understanding of life on Earth.

    Fred Bortz — Science and technology books for young readers (www.fredbortz.com) and Science book reviews (www.scienceshelf.com)

  3. Anonymous September 5, 2008 at 1:46 pm #

    by Josh Greenberger – http://JoshGreenberger.com

    Does the fossil record disprove the theory of evolution?

    (March 2008) The scientific concept of the origin of life on earth begins with the premise that life first appeared billions of years ago with the formation of microscopic organisms out of inanimate matter. In the billions of years which followed, small organisms evolved into higher and more complex forms of life through random mutations, and one species evolved into another.

    Over the years, a process referred to as “natural selection” weeded out those mutations and organisms less fit to survive than others. Thus, it was mostly the more “fit” that passed on their genetic character traits to subsequent generations. And that’s how we and all other life forms got here.

    On the surface, this sounds great. However, a deeper analysis of the underlying mechanism and the fossil record, leaves little doubt that mutations of a random nature could not possibly have been the driving force behind the development of life on earth.

    There has been opposition to the theory of evolution on the basis of whether a random process can produce organization. An analogy often given is, can a monkey on a typewriter, given enough time, produce the works of Shakespeare purely by random keystrokes? Let’s assume for the purpose of this discussion that this is possible — and that random mutations, given enough time, can also eventually produce the most complex life forms.

    Let’s begin by rolling a die (one “dice”). To get a “3,” for example, you’d have to roll the die an average of six times (there are six numbers, so to get any one of them would take an average of six rolls). Of course, you could get lucky and roll a 3 the first time. But as you keep rolling the die, you’ll find that the 3 will come up on average once every six rolls.

    The same holds true for any random process. You’ll get a “Royal Flush” (the five highest cards, in the same suit) in a 5-card poker game on average roughly once every 650,000 hands. In other words, for every 650,00 hands of mostly meaningless arrangements of cards (and perhaps a few other poker hands), you’ll get only one Royal Flush.

    Multi-million dollar lotteries are also based on this concept. If the odds against winning a big jackpot are millions to one, what will usually happen is that for every game where one person wins the big jackpot with the right combination of numbers, millions of people will not win the big jackpot because they picked millions of combinations of meaningless numbers. To my knowledge, there hasn’t been a multi-million dollar lottery yet where millions of people won the top prize and only a few won little or nothing. It’s always the other way around. And sometimes there isn’t even one big winner.

    How does this relate to evolution?

    Let’s take this well-understood concept about randomness and apply it the old story of a monkey on a typewriter. As mentioned earlier, for the purpose of this discussion, we’ll assume that if you allow a monkey to randomly hit keys on a typewriter long enough he could eventually turn out the works of Shakespeare. Of course, it would take a very long time, and he’d produce mountains and mountains of pages of meaningless garbage in the process, but eventually (we’ll assume) he could turn out the works of Shakespeare.

    Now, let’s say, after putting a monkey in front of a typewriter to type out Shakespeare, you decide you also want a copy of the Encyclopedia of Britannica. So you put another monkey in front of another typewriter. Then, you put a third monkey in front of third typewriter, because you also want a copy of “War And Peace.” Now you shout, “Monkeys, type,” and they all start banging away on their typewriters.

    You leave the room and have yourself cryogenically frozen so you can come back in a few million years to see the results. (The monkeys don’t have to be frozen. Let’s say they’re an advanced species; all they need to survive millions of years is fresh ink cartridges.)

    You come back in a few million years and are shocked at what you see. What shocks you is not what you find, but what you don’t find. First, you do find that the monkeys have produced the works of Shakespeare, the Encyclopedia of Britannica and “War and Peace.” But all this you expected.

    What shocks you is that you don’t see the mountains of papers of meaningless arrangement of letters that each monkey should have produced for each literary work. You do find a few mistyped pages here and there, but they do not nearly account for the millions of pages of “mistakes” you should have found.

    And even if the monkeys happened to get them all right the first time, which is a pretty big stretch of the imagination, they still should’ve type out millions of meaningless pages in those millions of years. (Who told them to stop typing?) Either way, each random work of art should have produced millions upon millions of meaningless typed pages.

    This is precisely what the problem is with the Darwinian theory of evolution.

    A random process, as depicted by Darwinian evolution and accepted by many scientists, even if one claims it can produce the most complex forms of life, should have produced at least millions of dysfunctional organisms for every functional one. And with more complex organisms (like a “Royal Flush” as opposed to a number 3 on a die), an even greater number of dysfunctional “mistakes” should have been produced (as there are so many more possibilities of “mistakes” in a 52-card deck than a 6-sided die).

    The fossil record should have been bursting with billions upon billions of completely dysfunctional-looking organisms at various stages of development for the evolution of every life form. And for each higher life form — human, monkey, chimpanzee, etc. — there should have been millions of even more “mistakes.”

    Instead, what the fossil record shows is an overwhelming number of well-formed, functional-looking organisms, with an occasional aberration. Let alone we haven’t found the plethora of “gradually improved” or intermediate species (sometimes referred to as “missing links”) that we should have, we haven’t even found the vast number of “mistakes” known beyond a shadow of a doubt to be produced by every random process.

    We don’t need billions of years to duplicate a random process in a lab to show that it will produce chaos every time, regardless of whether or not it might eventually produce some “meaningful complexity.” To say that randomness can produce organization is one thing, but to say that it won’t even produce the chaos that randomness invariably produces is inconsistent with established fact.

    A process that will produce organization without the chaos normally associated with randomness is the greatest proof that the process is not random.

    The notion that the fossil record supports the Darwinian theory of evolution is as ludicrous as saying that a decomposed carcass proves an animal is still alive. It proves the precise opposite. The relative scarcity of deformed-looking creatures in the fossil record proves beyond a doubt that if one species spawned another (which in itself is far from proven) it could not possibly have been by a random process.

    To answer why we don’t see many of the “mistakes” in the fossil record, some scientists point out that the genetic code has a repair mechanism which is able to recognize diseased and dysfunctional genetic code and eliminate it before it has a chance to perpetuate abnormal organisms.

    Aside from this not being the issue, this isn’t even entirely true. Although genetic code has the ability to repair or eliminate malfunctioning genes, many diseased genes fall through the cracks, despite this. There are a host of genetic diseases — hemophilia, various cancers, congenital cataract, spontaneous abortions, cystic fibrosis, color-blindness, and muscular dystrophy, to name just a few — that ravage organisms and get passed on to later generations, unhampered by the genetic repair mechanism. During earth’s history of robust speciation (species spawning new ones) through, allegedly, random mutation, far more genes should have fallen through the cracks.

    And, as an aside, how did the genetic repair mechanism evolve before there was a genetic repair mechanism? And where are all those millions of deformed and diseased organisms that should’ve been produced before the genetic repair mechanism was fully functional?

    But all this is besides the point. A more serious problem is the presumption that natural selection weeded out the vast majority, or all, of the “misfits.”

    A genetic mutation that would have resulted in, let’s say, the first cow to be born with two legs instead of four, would not necessarily be recognized as dysfunctional by the genetic repair mechanism. (I’ll be using “cow” as an example throughout; but it applies to almost any organism.) From the genetic standpoint, as long as a gene is sound in its own right, there’s really no difference between a cow with four legs, two legs, or six tails and an ingrown milk container. It’s only after the cow is born that natural selection, on the macro level, eliminates it if it’s not fit to survive.

    It’s these types of mutations, organisms unfit to survive on the macro level, yet genetically sound, that should have littered the planet by the billions.

    Sure these deformed cows would have gotten wiped out quickly by natural selection, since they had no chance of surviving. But how many millions of dysfunctional cows alone, before you even get to the billions of other species in earth’s history, should have littered the planet and fossil record before the first stable, functioning cow made its debut? If you extrapolate the random combinations from a simple deck of cards to the far greater complexity of a cow, we’re probably talking about tens of millions of “mistakes” that should have cluttered planet earth for just the first functioning cow.

    Where are all these relics of an evolutionary past?

    Did nature miraculously get billions of species right the first time? Of the fossils well-preserved enough to study, most appear to be well-designed and functional-looking. With the low aberration ratio of fossils being no more significant, as far as speciation is concerned, than common birth deformities, there seems to have been nothing of a random nature in the development of life.

    One absurd response I’ve gotten from a scientist as to why a plethora of deformed species never existed is: There is no such thing as speciation driven by deleterious mutation.

    This is like asking, “How come everybody leaves the lecture hall through exit 5, but never through exit 4?” and getting a response, “Because people don’t leave the lecture hall through exit 4.” Wasn’t this the question?

    What scientists have apparently done is look into the fossil record and found that new species tend to make their first appearance as well-formed, healthy-looking organisms. So instead of asking themselves how can a random series of accidents seldom, if ever, produce “accidents,” they’ve simply formulated a new rule in evolutionary biology: There is no such thing as speciation driven by deleterious mutation. This answer is about as scientific, logical and insightful as, “Because I said so.”

    It’s one thing for the genetic code to spawn relatively flawless cows today, after years of stability. But before cows took root, a cow that might have struck us as deformed would have been no more or less “deleterious,” from the genetic standpoint, than a cow that we see as normal. The genetic repair mechanism may recognize “healthy” or “diseased” genetic code, but it can’t know how many legs or horns a completely new species should have, if we’re talking about a trial-and-error crapshoot. If the genetic repair mechanism could predict what a functioning species should eventually look like, years before natural selection on the macro level had a chance to weed out the unfit, we’d be talking about some pretty weird, prophetic science.

    In a paper published in the February 21, 2002, issue of Nature, Biologists Matthew Ronshaugen, Nadine McGinnis, and William McGinnis described how they were able to suppress some limb development in fruit flies simply by activating certain genes and suppress all limb development in some cases with additional mutations during embryonic development.

    In another widely publicized experiment, mutations induced by radiation caused fruit flies to grow legs on their heads.

    These experiments showed how easy it is to make drastic changes to an organism through genetic mutations. Ironically, although the former experiment was touted as supporting evolution, they both actually do the opposite. The apparent ease with which organisms can change so dramatically and take on bizarre properties, drives home the point that bizarre creatures, and bizarre versions of known species, should have been mass produced by nature, had earth’s history consisted of billions of years of the development of life through random changes.

    To claim that the random development of billions of life forms occurred, yet the massive aberrations didn’t, is an absurd contradiction to everything known about randomness.

    Evolutionists tend to point out that the fossil record represents only a small fraction of biological history, and this is why we don’t find all the biological aberrations we should. But the issue here is not one of numbers but one of proportion.

    For every fossil of a well-formed, viable-looking organism, we should have found an abundance of “strange” or deformed ones, regardless of the total number. What we’re finding, however, is the proportional opposite.

    Evolution may have made some sense in Darwin’s days. But in the 21st century, evolution appears to be little more than the figment of a brilliant imagination. Although this imaginative concept has, in the years since Darwin, amassed a fanatical cult-like following, science, it is not. Science still needs to be proven; you can’t just vote ideas into “fact.” And especially not when they contradict facts.

    One sign of the desperation of evolutionists to get their fallacious message across is their labelling of all disproofs of evolution as “Creationism,” even when no mention of Creation or a deity is made. Ironically, it’s evolutionists’ dogmatic adherence to concepts that are more imagination than fact that smacks of a belief in mystical, supernatural powers. What evolutionists have done, in effect, is invented a new god-less religion and re-invented their own version of creation-by-supernatural-means. However, the mere elimination of God from the picture doesn’t exactly make it science.

    So if the development of life was not an accident, how did life come about?

    Well, pointing out a problem is not necessarily contingent upon whether or not a solution is presented. In this case, presenting an alternative may actually be counterproductive. Evolutionists often get so bogged down with trying to discredit an proposed alternative, frequently with nothing more than invectives, that they tend to walk away believing evolution must still work.

    The objective here, therefore, is to point out that Darwinian evolution does not fall apart because a solution being presented says it happened differently. The objective here is to show that the mechanics of evolution are incompatible with empirical evidence, verifiable science and common sense, regardless of whatever else may or may not take its place.

    For a true study of science, we need to put the theory of evolution to rest, as we’ve done with so many other primitive concepts born of ignorance. Science today is far beyond such notions as metals that turn into gold, brooms that fly, earth is flat, and mystical powers that accidentally create life. What all these foolish beliefs have in common is that they were popular in their own time, were never duplicated in a lab, and were never proven by any other means.

    We’d be doing society a great service if we filled our science textbooks with verifiable facts that demonstrate how science works, instead of scintillating fabrications that demonstrate how imaginative and irrational some scientists can get.

    by Josh Greenberger – http://JoshGreenberger.com

Leave a Reply

* Copy This Password *

* Type Or Paste Password Here *