Re: the reptilian egg: a `construction project' design argument 1/2

From: Stephen E. Jones (sejones@iinet.net.au)
Date: Sat Dec 30 2000 - 21:56:33 EST

  • Next message: Stephen E. Jones: "Re: the reptilian egg: a `construction project' design argument 2/2"

    Reflectorites

    As I will be un - sub - scribing from the Reflector on or before 1
    January 2001, this will be my last post on the Reflector to Chris.
    Therefore I wish to express my thanks to Chris for his stimulating
    questions, which have forced me to research the facts and clarify my
    ideas.

    I look forward to continuing debates with Chris on eGroups
    (creationevolutiondebate@egroups.com)

    May I take this opportunity to wish everyone a happy new Century and
    Millennium!

    --Original Message Text---
    From: Chris Cogan
    Date: Sun, 03 Dec 2000 16:50:17 -0600

    >SJ>Here is an example of what I call the `construction project' design
    >>argument, in this case the reptilian egg.
    >>
    >>Koestler (a non-theist writes): .... So the reptilian egg had to be
    >>provided with a large mass of yolk for food, and also with albumen
    >>the white of egg - to provide the water. Neither the yolk by itself,
    >>nor the egg-white itself, would have had any selective value.
    >>Moreover, the eggwhite needed a vessel to contain it, otherwise its
    >>moisture would have evaporated. So there had to be a shell made of
    >>a leathery or limey material, as part of the evolutionary package-
    >>deal. But that is not the end of the story. The reptilian embryo,
    >>because of this shell, could not get rid of its waste products. The
    >>soft-shelled amphibian embryo had the whole pond as a lavatory;
    >>the reptilian embryo had to be provided with a kind of bladder. It is
    >>called the allantois, and is in some respects the forerunner of the
    >>mammalian placenta. But this problem having been solved, the
    >>embryo would still remain trapped inside its tough shell; it needed a
    >>tool to get out. The embryos of some fishes and amphibians, whose
    >>eggs are surrounded by a gelatinous membrane, have glands on
    >>their snouts: when the time is ripe, they secrete a chemical which
    >>dissolves the membrane. but embryos surrounded by a hard shell
    >>need a mechanical tool: thus snakes and lizards have a tooth
    >>transformed into a kind of tin-opener, while birds have a caruncle -
    >>a hard outgrowth near the tip of their beaks which serves the same
    >>purpose and is later shed by the adult animal. ...
    >>Now according to the Darwinian schema, all these changes must
    >>have been gradual, each small step caused by a chance mutation.
    >>But it is obvious that each step, however small, required
    >>simultaneous, interdependent changes affecting all the factors
    >>involved in the story.

    >CC>False. It is not obvious. In fact it is simply *false*. This is the same
    >old crap, recycled for the billionth time, by
    >Koestler and now by Jones in quoting Koestler.

    So Chris *says*!

    The reason why this is "old" and "recycled for the billionth time" is
    because the Darwinists have never satisfactorily answered it
    (see tagline).

    CC>Doesn't Jones *ever* check his facts?

    I have come to regard this sort of thing from Chris as just bluff!

    In the 5+ years I have been on the Reflector, Chris has rarely (if ever)
    posted any facts (in the sense of quotes from the scientific literature) to
    support his arguments.

    I have repeatedly asked Chris to post his qualifications that give him
    the right to pontificate off the top of his head about evolution but he
    has never done so.

    Chris' `village evolutionism' might impress some people, but it has
    never impressed me. He has shown no evidence of actually reading the
    scientific evolutionary literature, so I assume that he just makes it up
    off the top of his head.

    Chris's arguments remind me of the sort of naive, primitive, pre-
    scientific philosophical evolutionism championed by Herbert Spencer:
            
            "Spencer's belief in the universality of natural causation was,
            together with his laissez-faire political creed, the bedrock of his
            thinking. It was this belief, more than anything else, that led him to
             reject Christianity, long before the great conflict of the eighteen-
             sixties. Moreover, it was his belief in natural causation that led him
             to embrace the theory of evolution, not vice versa." (Burrow, 1968,
             p.205)

    and:
            "His faith was so strong that it did not wait on scientific proof.
            Spencer became an ardent evolutionist at a time when a cautious
             scientist would have been justified at least in suspending judgement.
             ... for him the belief in natural causation was primary, the theory
             of evolution derivative." (Burrow, 1968, p.206)

    >SJ>Thus the liquid store in the albumen could not
    >>be kept in the egg without the hard shell. But the shell would be
    >>useless, in fact murderous, without the allantois and without the tin-
    >>opener.

    >CC>None of these are true. They rest on a series of false
    assumptions.
    >*NONE* of these additions needs to just pop into existence full-
    blown.

    So Chris says! But where are *his* "facts"?

    Stahl says that it is hard for paleontologists to even *imagine* the steps
    that led to the development of the "land egg":

            "It is easier to understand the stages by which the reptiles evolved
            temporal fenestrae and other distinguishing skeletal characters than
            to imagine the steps that led to the development of the "land egg."
            Paleontologists continue to speculate upon the way in which the
            enclosure of the embryo came about, however, because the matter
            is central to the broad question of reptilian origins. Study of the
            eggs laid by living reptiles has provided little insight into the
            evolution of the extraembryonic structures which gave protoreptiles
            their first advantage over other tetrapods. Rather than
            recapitulating the process of its evolution, the "land egg" develops
            in a specialized manner derived, no doubt, by abbreviation and
            reordering of an earlier procedure." (Stahl B.J., "Vertebrate
            History," 1985, p.268)
            
    Yet Chris thinks *he* can explain it without needing to know any of
    the details!

    CC>For example, a very thin, but still somewhat
    >protective, membrane

    We are not talking about "a ...membrane" but *four* membranes:

            "The eggs of land vertebrates such as reptiles and birds have four
            different membranes in addition to the shell. These are the amnion,
            the allantois thus yolk sac, and the chorion... The amnion encloses a
            fluid-filled chamber housing the embryo which can thus develop in
            an aquatic medium even though the egg as a whole may be laid on
            dry land. The allantois functions as a receptacle for the urinary
            wastes of the developing embryo, and its blood vessels, which lie
            near the shell, function in gas exchange. The yolk sac, as its name
            indicates encloses the yolk, which is food material used by the
            developing embryo. The chorion is an outer membrane surrounding
            the embryo and the other membranes." (Keeton W.T., Gould J.L. &
            Gould C.G., "Biological Science," 1986, p.437)

    CC> might have formed

    Pigs "might have" or "may have" flown too! But where is the evidence
    that they *did*?

    What is Chris' *evidence* that this actually happened?

    And more importantly *why* would it happen?

    CC> around the developing organism (which may have been little different
    from
    >a *slightly* incomplete tadpole).

    Chris shows by this elementary blunder that he himself doesn't know
    the "facts" about how an egg develops. The membranes do not form
    around the developing organism, but around the developing *ovum*:

            "In reptiles-and in birds and mammals, too-the ovum or egg is one
            of a large number of ova enclosed in the membranous follicles
            (Latin for "small bags") of the ovaries. These follicles may number
            as many as 25,000 in some reptiles and birds, but only a few ripen
            each breeding season. The ripe ovum accumulates a large yolk and
            in time bursts from its follicle and enters the oviduct of the reptiles.
            If sperm are present, the ovum will be fertilized while moving down
            the oviduct. Here it also acquires a deposit of albumen. Descending
            into the uterus, the ovum acquires its various membranes and finally
            the protective shell." (Stivens D., "The Incredible Egg, 1974,
            p172).
            
    And these membranes all develop *simultaneously*:

            "In the present series of events, gelatinous albumen and the material
            of the shell are deposited around the fertilized ovum before the
            embryo or its membranes have proceeded far in their formation.
            The yolk sac, which is probably the oldest of the accessory
            structures phylogenetically, develops simultaneously with the other
            extraembryonic membranes (Fig. 7.10). An extension of the gut
            wall of the embryo, it spreads downward to cover the large mass of
            yolk upon which the growing embryo is perched. As it does so, a
            fold at the periphery of the animal's expanding body wall rises up
            and eventually covers the whole embryo. The inner side of the fold
            becomes the amnion, and the outer part, split away, the chorion, a
            membrane which envelops all the other living tissues within the
            shell. From the hindgut beyond the stalk of the yolk sac, the
            allantois begins as a pocket and then swells outward to fill the space
            within the chorion not already occupied by yolk and the embryo in
            its amniotic capsule. The capillary network of the embryo extends
            throughout the extraembryonic membranes as they develop and
            maintains them as adjuncts to the body until the time of hatching."
            (Stahl B.J., "Vertebrate history: Problems in Evolution," 1985,
            p.269)

    That is because they *all* need to be present together:

            "All the extraembryonic membranes in the "land egg" of a modern
            reptile must complete their formation normally if the embryo is to
            sustain itself. The yolk sac is of crucial importance, because
            nutritive materials from the yolk mass can enter the body only by
            passing through the vessels in its surface. The allantois also cannot
            fail: it serves as the respiratory organ for the embryo, since blood
            coursing through it loses carbon dioxide and receives oxygen by
            diffusion through the adjacent chorion and porous shell. In addition,
            its central cavity stores nitrogenous wastes produced by the actively
            metabolizing, embryonic cells. Blood reentering the embryo from
            the allantoic vessels restores to the body water that has Wen
            resorbed from the excreted waste and also adds some that passes
            into the egg from the environmental air. The exterior of the embryo
            is kept wet by a liquid that accumulates within the amnion. Unlike
            pond water, to which it is often compared, the amniotic fluid does
            not act as an oxygen-bearing medium for the embryo. It is an
            adaptation for protecting the developing, animal against shock and
            for preventing it from resting against the membranes in the shell and
            sticking to them." (Stahl, 1985, p.270)

    So the evidence of embryology is that Koestler is right:

            "Each of these changes, if they had occurred alone, would have
            been harmful.... They are all interdependent within the organism
             which is a functional whole, and not a mosaic. " (Koestler A.,
            "Janus: A Summing Up," 1983, pp.175-176)

    CC>This thin membrane could easily dry up and crack open on its own as the
    >organism completed its development, so no
    >"tin opener" would be needed at this stage.

    Note: "could easily".

    CC>Further, the albumen itself may
    >have initially been little more than a
    >bit of water and a small amount of dissolved nutrients (if there was
    any
    >albumen at all!).

    Note: "may have".

    Notice that Chris does not *need* any actual facts! By applying the
    Darwinist, Swiss-army knife, all-purpose *system* of thinking (i.e.
    breaking things down into small bits), it is possible to explaining
    *anything*, as Dawkins points out:

            "To 'tame' chance means to break down the very improbable into
            less improbable small components arranged in series. No matter
            how improbable it is that an X could have arisen from a Y in a
            single step, it is always possible to conceive of a series of
            infinitesimally graded intermediates between them. However
            improbable a large-scale change may be, smaller changes are less
            improbable. And provided we postulate a sufficiently large series of
            sufficiently finely graded intermediates, we shall be able to derive
            anything from anything else, without invoking astronomical
            improbabilities." (Dawkins R., "The Blind Watchmaker," 1991,
            pp.317-318)

    Dawkins continues that this way of thinking enables the Darwinist to
    "explain prodigies of apparent miracle":

            "It is the contention of the Darwinian world-view that both these
             provisos are met, and that slow, gradual, cumulative natural
             selection is the ultimate explanation for our existence. If there are
             versions of the evolution theory that deny slow gradualism, and
            deny the central role of natural selection, they may be true in
            particular cases. But they cannot be the whole truth, for they deny
             the very heart of the evolution theory, which gives it the power to
             dissolve astronomical improbabilities and explain prodigies of
            apparent miracle." (Dawkins, 1991, p.318)

    Notice that the Darwinist system of thinking would be able to explain
    a thing, *even if it didn't happen that way*. For example, the four
    membranes of the first reptilian egg could have appeared *all at once*
    but the Darwinist system of thinking could always explain it as
    happening one-by-one.

    Thus the Darwinist system of thinking that Chris uses here is delusory,
    because it gives only the *appearance* of knowledge, as Colin
    Patterson realised:

            "Well, what about evolution? It certainly has the function of
            knowledge but does it convey any? Well we're back to the question
            that I've been putting to people. "Is there any one thing you can tell
            me about evolution?" The absence of answers seems to suggest that
            it is true, evolution does not convey any knowledge or if so, I
            haven't yet heard of it. ... I want to ... make another point about
            evolution being an anti-theory that conveys anti-knowledge. ... That
            must say something about evolution. Seems to me we have another
            statement that has the appearance of knowledge, but, in fact,
            contains none, a piece of anti- knowledge derived from the
            evolutionary theory." (Patterson C., "Evolutionism and
            Creationism," Transcript of Address at the American Museum of
            Natural History, New York City, November 5, 1981, pp2,5)

    Chris is like Inspector Snikwad, the cartoon character in "What's
    Darwin Got to Do With It?" Inspector Snikwad had one all-purpose
    solution to every crime: "the butler did it":

            "The Case of the Usual Suspects
            
            [Watson:] I was reading my medical journal in our Baker Street flat
            when Holmes came in. He was carrying an edition of the morning
            paper which contained a sensational story of the murder of
            Professor Hannibal.
            
            [Holmes:] "You mean Alphonse Hannibal, the famous big-game
            hunter?"
            
            [Watson:] The same. famous for his uncanny ability to track
            elephants. the ones he didn't kill, he brought back to his private big-
            game reserve on his estate. Holmes then told me that he would not
            be able to look into the matter himself. He said that Inspector
            Snikwad from the National Academy of Detectives would head up
            the investigation, and that I would be welcome to come along. ...
            
            [Snikwad:] Professor Hannibal was not an easy man to like. He
            lent money to three of his neighbors who wanted to avoid the
            embarrassment of borrowing from the bank. But he charged a
            huge amount of interest in exchange for keeping quiet. He had
            numerous indiscreet affairs He mistreated the animals on his game
            reserve He was loud, boastful, obnoxious, arrogant, and had foul
            temper and bad breath. Yesterday morning, he was found trampled
            to death on the grounds of his estate. The butler did it.
            
            [Watson:] The butler did it? my dear Snikwad! how do you know?
            
            [Snikwad:] Because the butler *always* does it! haven't you
            read *anything*?
            
            [Watson:] But since he was so unpopular, surely there must be
            other suspects.
            
            [Snikwad:] I see no other suspects. the butler did it...Our only
            job is to show how he did it.
            
            [Watson:] ... When we arrived at the station, Sgt. Perkins filled us
            in on some of the details of the murder scene. Professor Hannibal's
            body had been found inside the walls of his big-game reserve. The
            ground around the body showed signs of a struggle, but most of the
            footprints had been obliterated. However, there were several,
            distinct circular indentations still visible nearby. [these look like
            elephant tracks]
            
            [Snikwad:] Since we know the butler did it, all we need to do is
            explain the mechanism. My guess is that the butler strapped a
            couple of large fireplace logs onto his feet. This would explain the
            condition of the body, and it would explain the circular impressions
            nearby. Sgt. Perkins, check the wood supply. if any wood is
            missing, you'll know you have your man. Come along, Watson. our
            work is finished here."

            (Newman R.C., et al., "What's Darwin Got to Do With It?"
            2000, pp.127-132)

    CC>The allontois would not
    >need to be developed until the period inside the shell became so long
    that
    >something had to be done with waste.

    And when it was needed, along came another random mutation, right
    on cue:

            "The opportune appearance of mutations permitting animals and
            plants to meet their needs seems hard to believe. Yet the Darwinian
            theory is even more demanding: A single plant, a single animal
            would require thousands and thousands of lucky, appropriate
            events. Thus, miracles would become the rule: events with an
            infinitesimal probability could not fail to occur. Much as in The
            Swiss Family Robinson, which I used to read in my childhood,
            rescue would always occur at the right moment, and this would
            have had to have happened throughout the ages. One could admit
            that one bacterium out of billions and billions can be the "lucky
            preadapted" one, but the number of reptiles evolving into mammals
            or of primates evolving into men, did not exceed a few tens of
            thousands and often fewer; the chances of the appearance of
            "useful" mutations therefore decrease in the same ratio and become
            almost nonexistent." (Grasse P.-P., "Evolution of Living
            Organisms," 1977, p.103).

    BTW, this also shows that Chris is bluffing about him knowing the
    facts of the origin of the amniotic egg, because the theory is that the
    Allantois was the *first* of the extraembryonic membranes to develop:

            "According to Szarski (1968), the first of the extraembryonic
            membranes to evolve would have been the allantois." (Carroll
            R.L.,"Vertebrate Paleontology and Evolution," 1988, p.197)

    CC>And *this* would not need to be done until the albumen became a
    >substantial portion of the contents of
    >the membrane.

    Note Chris' words: "need to be done". This is Lamarckism. But Chris is
    in good company. Ever since Darwin, Darwinists have always called on
    Lamarck to get them out of tight spots:

            "As time went on, he [Darwin] became ever more receptive to the
            Lamarckian theory, until by 1875 he acknowledged that each year
            he came to attribute more and more to the agency of use and
            disuse. Thus the older theory of adaptation was thrown into the
            breach when natural selection was found wanting." (Himmelfarb G.,
            "Darwin and the Darwinian Revolution," 1996, p.321)

    CC>And *this* would not need to be done until the whole was
    >released a significant period of time
    >before it was developed enough to survive on its own.

    Note the Lamarckian "need to be done" again.

    CC>The "tin opener"
    >would not be needed until the
    >membrane became strong enough to pose a problem for the emerging
    >organism.

    And again!

    CC>And it would not need a very
    >strong and sturdy and long lasting shell until the entire process of
    >development within the shell took sufficiently
    >long as to make a thicker or harder shell needed.

    And again!

    Also remember that Michael made a big thing about amphibians already
    had a hard shell. Darwinism can explain everything and its opposite!

    >SJ>While at the borderline of being too hard to get out of, the "tin opener"
    >>could begin to develop. Once it was
    >>present in some small way, the shell could continue to be made thicker and
    >>more durable.

    CC>Each, and all, of these items could develop a bit at a time, as needed and
    as
    >genetic modifications occurred to
    >support some slight increase in the development of one or the other of
    >them.
    >
    >Etc., etc., etc.

    Yes, "Etc., etc., etc."! Notice that Chris does not need to know any
    more *details* about "these items". They are *just* "items". The
    Darwinian all-purpose *system* of explanation can explain these
    "items" without needing to know *anything* about them!

    All that is needed is "genetic modifications" to have "occurred" at the
    right place, at the right time, to the right animals, and the `blind
    watchmaker' can do the rest.

    But if the occurrence of the right "genetic modifications" when they are
    needed is the crucial factor, then Darwinian natural selection is only a
    minor player. The true cause of the origin of the reptilian egg is the
    origin of those "genetic modifications":

            "If in one respect natural selection may be criticized for trying to
            explain too much; in another it may be thought to explain too little.
            Even at the time of its publication, a common charge brought
            against the Origin was its failure to establish a vera causa for
            evolution. As Samuel Butler later put it: "The 'Origin of Variation,'
            whatever it is, is the only true 'Origin of Species.'" Natural
            selection, critics complained, might account for the persistence of
            some variations and the disappearance of others, but it did not
            account for the origin of the variations themselves. And only an
            explanation of the origin of the variations would constitute a vera
            causa. One critic compared Darwin unfavorably, in this respect,
            with his predecessors, Lamarck and the author of the Vestiges,
            who, however benighted, at least had the forthrightness to propose
            specific explanations for the origin of the variations. And even in his
            own camp Asa Gray and others confessed themselves troubled by
            this inadequacy in the theory. (Himmelfarb G., "Darwin and the
            Darwinian Revolution," 1996, pp.321-322)

    Chris, whether he realises it or not, has helped confirm my thesis that
    this is part of a `construction project.' A series of "genetic
    modifications" occurring right on cue, where and when they are
    needed, in *one* line of amphibians, looks more like an intelligently
    designed `construction project' than the blunderings of a `blind
    watchmaker'.

    All the more so, when it is realised that this new egg design, was the
    blueprint for all future reptile, bird and mammal design:

            "The reptilian egg is, in fact, a blueprint for the eggs of mammals
            and for live birth. In the more complex mammalian egg, one of the
            membranes inherited from the ancient reptilian egg, the chorion,
            comes into close contact with the wall of the uterus to form the
            placenta. Linked with the blood vessels of the allantois, the placenta
            supplies oxygen and nutriment to the developing embryo and
            carries away carbon dioxide and waste materials. (Stivens D., "The
            Incredible Egg," 1974, p170)

    CC>You are *wasting* our time with this witless, empty crap.

    Notice how Chris tries to discourage criticism of evolution. A
    confident theory would *welcome* criticism:

            "In the final analysis, it is not any specific scientific evidence that
            convinces me that Darwinism is a pseudoscience that will collapse
            once it becomes possible for critics to get a fair hearing. It is the
            way the Darwinists argue their case that makes it apparent that they
            are afraid to encounter the best arguments against their theory. A
            real science does not employ propaganda and legal barriers to
            prevent relevant questions from being asked, nor does it rely on
            enforcing rules of reasoning that allow no alternative to the official
            story. If the Darwinists had a good case to make, they would
            welcome the critics to an academic forum for open debate, and they
            would want to confront the best critical arguments rather than to
            caricature them as straw men. Instead they have chosen to rely on
            the dishonorable methods of power politics." (Johnson P.E., "The
            Wedge of Truth," 2000, p.141)

    CC>It has been
    >*massively* refuted dozens of times before, both on this list and in the
    >empirical literature.

    Notice the exaggeration: "*massively* refuted dozens of times ". This
    looks to me to be the `body language' of someone who knows deep
    down his theory is weak.

    I have been on this List since 1995 and I cannot recall the origin of the
    reptilian egg even being discussed *once* let alone having been
    "refuted dozens of times".

    And maybe Chris can quote some of that "empirical literature"?

    CC>Do you *ever* check your facts?

    Yes, I do. See above. In addition to Stahl above saying that:

            "It is easier to understand the stages by which the reptiles evolved
            temporal fenestrae and other distinguishing skeletal characters than
            to imagine the steps that led to the development of the "land egg."
            Paleontologists continue to speculate upon the way in which the
            enclosure of the embryo came about...." (Stahl B.J., "Vertebrate
            History," 1985, p.268);

    and Stivens admitting that:

            "No one knows for certain how this wonderful egg evolved."
            (Stivens D., "The Incredible Egg: A Billion Year Journey," 1974,
            p171)

    Colbert says that "there is no fossil evidence" of the origin of the amniote
    egg:

            "The reptiles were derived from the amphibians, specifically from
            certain anthracosaur labyrinthodonts, the transition from amphibian
            to reptile taking place during the Carboniferous period of earth
            history. Of course the final crossing of the threshold from the
            amphibians to the reptiles occurred with the perfection of the
            amniote egg, but of this there is no fossil evidence. The oldest
            known amniote egg, which is from lower Permian sediments in
            North America, represents a time long after the reptiles had become
            well established on the land." (Colbert E.H., "Evolution of the
            Vertebrates," 1992, p.102)

    and therefore "speculations may be in order":

            "Even though the oldest known reptile egg is far removed in time
            from the first amniote egg, some speculations may be in order"
            (Colbert, 1992, p.102)

    >SJ>Each of these changes, if they had occurred alone, would
    >>have been harmful, and the organisms thus affected would have
    >>been weeded out by natural selection (or rather, as suggested
    >>above, by 'natural elimination').

    >CC>They would *only* have been harmful if they had formed *completely* or
    >at least *substantially* without some development in the others.

    This misses the point. Darwin realised that for natural selection to be able to craft
    the eye, it would have to have the power to eliminate anything that was not
    immediately useful:

            "It may metaphorically be said that natural selection is daily and hourly
            scrutinising, throughout the world, the SLIGHTEST variations;
            REJECTING THOSE THAT ARE BAD, preserving and adding up all
            that are good; silently and insensibly working, whenever and wherever
            opportunity offers, at the improvement of each organic being in relation to
            its organic and inorganic conditions of life. We see nothing of these slow
            changes in progress, until the hand of time has marked the lapse of ages,
            and then so imperfect is our view into long-past geological ages, that we
            see only that the forms of life are now different from what they formerly
            were. (Darwin C.R., "The Origin of Species," 6th Edition, 1928, reprint,
            p.84. My emphasis)

    CC>But there is no evidence that they *did* form this way,

    There is no evidence that they did *not* form this way, either.

    CC>and there is no basis in NET for thinking that they did.

    First, I presume this acronym "NET" (for Naturalistic Evolutionary
    Theory) is just something that Chris made up to sound authoritative?
    AFAIK there is no such acronym used in the current evolutionary
    literature. The only evolutionary theory that is actually defended in the
    modern evolutionary literature is Neo-Darwinism. So "NET" is just Chris'
    private version of evolution.

    Second, this shows that Chris just makes it up as he goes along and does
    not himself keep up with modern evolutionary literature. Today, as
    Futuyma points out, it is regarded as "the rule rather than the exception"
    that evolution is *mosaic*, i.e. "higher taxa emerge not by coherent
    transformation of all or even most of their features, but by sequential
    changes in various traits":

            "The term MOSAIC EVOLUTION refers to differences among
            characters in their rate of evolution within a lineage. Compared to
            Carboniferous amphibians, for example, frogs have an ancestral
            number of aortic arches (2), but a derived number of fingers (4);
            humans have a derived number of aortic arches (1), but an ancestral
            number of digits (5). Humans (Homo sapiens) and chimpanzees
            (Pan troglodytes) differ strikingly in morphology, but their DNA
            and proteins are extraordinarily similar, suggesting that
            morphological and biochemical evolution have proceeded at
            different rates (King and Wilson 1975). Mosaicism of evolution is
            the rule rather than the exception; higher taxa emerge not by
            coherent transformation of all or even most of their features, but by
            sequential changes in various traits (Schaeffer 1956). In all but its
            feathers and a few other bird-like features, for example,
            Archaeopteryx had the reptilian characters of the small dinosaurs
            that were its close relatives (Figure 14 in Chapter 11)." (Futuyma
            D.J., "Evolutionary Biology," 1986, p.293)

    [continued]

    Steve

    --------------------------------------------------------------------------
    "Evolutionary biologists have a habit of ignoring the most pertinent
    criticisms of their theory until they can decently call them out-of-date."
    (Berlinski D., "Denying Darwin: David Berlinski and Critics,"
    Commentary, September 1996, p.26.
    http://www.commentarymagazine.com/9609/letters.html)"
    Stephen E. Jones | Ph. +61 8 9448 7439 | http://www.iinet.net.au/~sejones
    --------------------------------------------------------------------------



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