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Speciation: Or maybe not?

At Wired Science, we are informed “Birth of New Species Witnessed by Scientists” (November 16, 2009):

On one of the Galapagos islands whose finches shaped the theories of a young Charles Darwin, biologists have witnessed that elusive moment when a single species splits in two.

In many ways, the split followed predictable patterns, requiring a hybrid newcomer who’d already taken baby steps down a new evolutionary path. But playing an unexpected part was chance, and the newcomer singing his own special song.

My best guess is that if the girls stop dropping by, he will soon be either singing a different tune or a bachelor. Note the qualifications:

The future of the species is far from certain. It’s possible that they’ll be out-competed by other finches on the island. Their initial gene pool may contain flaws that will be magnified with time. A chance disaster could wipe them out. The birds might even return to the fold of their parent species, and merge with them through interbreeding.

But whatever happens, their legacy will remain: New species can emerge very quickly — and sometimes all it takes is a song.

Hmmm. If a song is really all it takes, it probably isn’t a different species.

Siamese yowl differently from the European cat, and their behaviour is often different, but they are not a different species.

Typically, species prefer their own when they can meet n’ greet easily. Sometimes that won’t happen. Successful species are often flexible about intermediates – which likely hinders speciation.

Only a Darwinist would be this desperate to find an example of speciation.

In this news story, reporter Brandon Keim deserves considerable credit for admitting the difficulties. Maybe some fragments of the message about the problems are getting through.

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32 Responses to Speciation: Or maybe not?

  1. I suggest all here view the lecture by the Grants at Stanford University just about a year ago. It can be accessed via ITunes U. Go to Stanford and the first option is courses. Select that. At the bottom is a series titled Darwin’s Legacy.

    One of the lectures is about the Galapagos finches and given by the Grants. There is absolutely nothing threatening to ID in the lecture and after I watched the lecture, I said to myself, thank you for an interesting discussion and ID is as strong as ever or maybe even stronger.

  2. Jerry at 1, I never supposed that any of it was “threatening” to ID. I just wondered how or why anyone would assume that a new species was developing, based on this slender line of evidence.

    I am glad if someone is keeping an eye on the Galapagos finches. But I no more believe that they are speciating – as I said above – than that the Rag Doll cat is speciating from the Siamese.

    In fact, a relative has advised me this very evening that she has acquired a cat whose parents are respectively Rag Doll and Siamese.

    It looks odd, but what do I know? If she looks after it well, what do I care?

  3. Deciding what is or is not a species, like so many things in science, is not as simple as it might first appear.

    Australian philosopher of science John S Wilkins, whom I have quoted before, has just published a book entitled Species: A History of the Idea . In the course of the research for the book he compiled a list of 26 distinct species concepts.

    Like it or not, speciation happens and has been observed.

  4. Denyse,

    The answer is that there is no speciation. They are all one species that can inter breed which is the most common usage of the term and how people like Dawkins and Coyne use it and most of biology. The Grants discuss the concept of speciation and its problems. It is well known that the used of the term is dicey or as I say on another thread specious. But Darwin’s title was the Origin of Species and so we must worship whatever it means at the moment.

    Seversky has just indicated that the term is useless because of the 26 different species concepts so how can such a term be used in a science setting. Watch the Darwinists and how they use the term. Now you see a usage, now you don’t. They are David Copperfield in action.

    By the way watch them flock to the discussion now that the specious species genie is out of the box.

  5. “Like it or not, speciation happens and has been observed”

    What is there not to like? The only thing is what are we supposed to like? Which of the 26 concepts is least likable? Which is most likable? Can we love any of them?

  6. Seversky,

    Like it or not even YECs accept “speciation” even with all of its ambiguities.

  7. I fail to see how any definition of speciation that doesn’t involve the addition of novel traits that can be reasonably extrapolated into macroevolution is of importance in this debate.

  8. Too bad Wired doesn’t link to the Grants’ research. It would be interesting to see their data/conclusions.

    But I think the relevant point in this debate is made by the following paragraph.

    “No exact rule exists for deciding when a group of animals constitutes a separate species. [...] But after at least three generations of reproductive isolation, the Grants felt comfortable in designating the new lineage as an incipient species.” – Wired

    Note the reproductive isolation. This is the hallmark of speciation. I can’t remember where I read it (possibly in one of Richard Dawkin’s books, but the paper seems to be here: Speciation through sensory drive in cichlid fish), but apparently, some cichlid are divided into two main colours. One is red, and the other blue. They will not mate with each other, until the researchers artificially change the colour of the light in the tank, making the red ones blue or vice versa. When the colours aren’t an issue, apparently the breeding is successful, and the offspring were fertile. Also mentioned here: Cichlid Fish Speciation, which gives some background and highlights some concerns.

    As to jerry at 4, you say “The answer is that there is no speciation. They are all one species that can inter breed which is the most common usage of the term…

    I agree with you that the finches can interbreed freely. But as the above fish research shows, for one reason or another, some species may decide on a feature (size/song) to split over. The Wikipedia article on speciation could be better, but as usual provides a springboard for a better understanding of this topic, and some other/better examples.

    tl;dr If the finches are not breeding with each other, for whatever reason, there is reproductive isolation, and therefore speciation.

  9. Also, to jerry at 4/5, I would argue that the pedantical list of 26-27 different types of ways to classify species probably does not come up in a biologist’s daily routine. I would say it’s like the 60-ish (didn’t want to count them all) cloud types that Wikipedia lists.

    Did you know that clouds could be classified into 60+ different categories? I honestly had no idea. Imagine learning that to be a TV weather-person.

    Science and math in particular are quite special in that they can be extremely pedantic about symbols and definitions. But I think that most people would agree with me if I bottom-lined it as such:

    tl;dr Clouds contain a visible mass of water droplets. Species cannot/do not breed with other species.

  10. ShawnBoy,

    The point is to muddy the waters such that anyone who disagrees with any part of the theory of evolution is made out to adhere to a fixity of species.

    That way you don’t have to address any real arguments, just show that speciation occurs.

    Just so you know… :)

  11. In the evolution debate nobody gives a rats rear end about speciation per se. It is as ShawnBoy says the origin of novel complex capabilities that is the real issue. Whether two populations decide to ignore each other for breeding purposes or not is really not of much interest. It happens. Whoopie Doo.

    Now that is not to say that speciation is not an interesting topic for some and one that should not be studied. But as far as what “The Debate” is all about, speciation or the origin of species is for the most part a yawner. A new finch in our lifetime that ignores another finch near by when it is time to do the fandango. Be still my heart.

    The concept of speciation and why inability to breed is at the essence of the real debate is that the population that is isolated somehow must not interbreed so that gene flow can take place and thus prevent the population from going off on its merry way to eventual macro evolution and the possibility of novel complex capabilities. This can apparently only theoretically take place in small isolated populations.

    The true Darwinist believer, asserts that given enough time and enough isolation there will be a steady build to a new complex capability through these speciation events. The only trouble is that such a process has never been observed in the past or in the current suite of species on the planet today. Somehow the dog ate the evidence for all the millions of such events which must have happened for common descent to be true in the microbes to man scenario.

    So the individual speciation event is a ho hummer. The real action is in the mythical event that never seems to materialize but which the true believer worships and adores and says that only given enough time it will appear. Sort of like the end of the world predictions that happen every 10 years or so. As Will Provine says you must have faith to be a true believer. Because there is no evidence.

    So for all you Darwinists out there. Keep the Faith. Give me that old time conviction. Amen Brother.

  12. So they have finally confirmed that species actually exist? Darwin didn’t seem to sure, even though he claimed to be giving an account of their origins.

  13. Like it or not, speciation happens and has been observed.

    Which definition of “species” did Darwin use?

    You keep pointing to that book, have you actually read it? If so, you’re certainly familiar with the idea that species aren’t real, they don’t actually exist.

    So how can you assert:

    Like it or not, speciation happens and has been observed.

    Species exist when it’s convenient for them to do so, and species don’t exist when it’s inconvenient that they do?

    Nice. This is science?

  14. To be precise, what is at issue in the research reported by the Grants is what is known as “secondary contact”. This is what happens after a sub-population has become reproductively isolated from the population from which it was derived. According to Ernst Mayr and Theodosius Dobzhansky (two of the founders of the “modern evolutionary synthesis”), speciation is the result of genetic isolation resulting from geographic isolation: the members of two geographically separated populations of organisms no longer interbreed, and therefore genetic differences between the two populations accumulate over time.

    This process, commonly known as allopatric speciation, can be considered to consist of six discrete successive stages:

    1) Vicariance: A subpopulation becomes geographically isolated from its former panmictic conspecifics;

    2) Divergence: The genomes of the members of the vicariant subpopulation diverge from the genomes of the members of the panmictic source population as the result of various genetic mechanisms (see http://evolutionlist.blogspot......awman.html );

    3) Reproductive Isolation: The reproductive anatomy, physiology, and behavior of the members of the vicariant subpopulation diverge from the reproductive anatomy, physiology, and behavior of the members of the original source population, resulting in reproductive isolation and (eventually) reproductive incompatibility;

    4) Secondary Contact: Successful hybridization between members of the diverging sub-population and the original source population decreases in frequency as the result of pre-zygotic and post-zygotic isolating mechanisms (see http://en.wikipedia.org/wiki/Isolating_mechanisms );

    5) Reinforcement: Hybrids continue to decrease in frequency as non-hybrids increase in frequency as the result of microevolutionary mechanisms (i.e. natural selection, genetic drift, and inbreeding depression), resulting in reinforcement of reproductive isolation and species boundaries; and

    6) Maintenance: Species incompatibility is continuously reinforced via pre-zygotic and post-zygotic isolating mechanisms, resulting in continued genotypic and phenotypic divergence.

    This is why Alfred Russell Wallace entitled his paper (which he mailed to Darwin in April 1858), “On the Tendency for Varieties to Depart Indefinitely from the Original Type.”

    Note that none of these stages is absolutely defined; rather, they integrade in what Darwin characterized as an “insensible series”. Also note that stages 4 through 6 can be condensed into one stage (i.e. “reinforcement”), in which reproductive incompatibility increases steadily over time.

    This is the theoretical model; what actual empirical studies have shown is that diverging phylogenetic lines frequently become reintegrated, separating and then re-integrating more than once. Sometimes they become sufficiently reinforced that they remain separate and diverge continuously, and sometimes they “collapse” back into a single, panmictic “species”.

    The importance of all of this to the theory of macroevolution is that divergence is divergence: phylogenetic divergence via reproductive isolation is macroevolution. Speciation is simply the first stage in the origin of all higher taxa.

    Therefore, what is ultimately at issue between non-YEC ID supporters is not speciation per se nor the mechanisms by which it occurs or is reinforced, but rather whether there are “natural” limits to the degree of divergence that can take place as a result of the mechanisms that comprise the “engines of variation”.

    This is not a question that can be answered via pure theoretical (i.e. mathematical) speculation. However, compelling a model may appear, it must be tested empirically to see if it conforms to the evidence from nature. This is what evolutionary biologists do all the time, and what ID theorists seem either unable or unwilling to do. Until this situation changes (if it ever does), no reputable scientist will take ID seriously.

  15. I was going to write on what Darwin thought a species was, but I think jerry at 11 brings up some other points.

    The act of speciation creates two distinct, non-interbreeding populations, where good mutations would theoretically be able to affect one population but not the other.

    Darwin’s experience was that speciation can happen even on islands, where they’re just far enough away to prevent interbreeding of the finches between the islands. Richard Dawkins in The Ancestors’ Tale also provided another example with salamanders in California being an example of a Ring Species. Therefore, speciation doesn’t have to happen in small, isolated populations. It just needs something (physical barrier/distance/sexual selection) to separate sub-populations.

    And, you also raised “macro-evolution”. This is an interesting discussion, because macro-evolution (as you define it) is really just a continuation of micro-evolution, on a longer time scale. Therefore, there is only evolution, which in the relatively short term does small changes, and in the long term does large changes.

    An interesting article that I recently came across was about the baby with the six fingers. Have you seen this? Baby with 6 Fingers

    Now I think that this is a perfect example of a positive mutation. The baby is healthy, and since other members of his family carry this mutation, it seems it’s not likely to hurt reproductive fitness. I would also argue that this may fit under your definition of macro-evolution. It’s a markedly different hand than some 6.5 other billion people in the world, and yet will function just fine (or possibly better) than the rest of us. These types of minor steps (if you can call an extra finger minor) are what evolution is all about.

    Speciation happens only once in a while, and is far easier to see generations after the fact. Meanwhile, mutations can happen in any population, and may be relatively major mutations. Darwin put these two ideas together to form his theory of evolution.

  16. I was going to write on what Darwin thought a species was, but I think jerry at 11 brings up some other points.

    Good luck. Darwin was very muddled on this issue.

    You see, he needed species, in order to argue that they were not immutable/fixed, so that he could make his case against special creation.

    But he also needed for there to be no such thing as species.

    As might be expected, confusion results, and Darwin was not immune.

  17. An interesting article that I recently came across was about the baby with the six fingers.

    It’s still just a finger. Given that a pathway for the formation of fingers in development is already known to exist, the “sudden appearance” of another finger on the hand doesn’t seem that far-fetched. But how does it explain the origin of fingers?

  18. DCX,

    The problem with gradualism leading to macro evolution is that it has to leave a trail and at each step of the trail there are potential branchings. But there is no evidence that any of these trails exist/existed or that any branchings took place. They are just not there. Occasionally you will get what is supposed to be a series of intermediaries but in reality there should be thousands for each transition. And each of these intermediaries represents another possible path that could have been taken as well as stasis or the staying put.

    But they are just not there. If they were, we would be hearing it from a thousand sources on this site. They would be taking numbers to tell us how dumb we are and can’t we see the obvious examples. But all we get is silence. And the amazing thing is that each critic of ID knows they have nothing and will just not admit it. They still have faith that it happened even if there is no evidence for it. Incredible human behavior don’t you think. I really do not know how they can look at themselves in the mirror each day.

  19. jerry,

    Occasionally you will get what is supposed to be a series of intermediaries but in reality there should be thousands for each transition.

    How did you arrive at the estimate of thousands?

    Do you have an estimate of the probability that an individual organism will leave fossil remains and be discovered? Do you have an estimate of the number of organisms that ever lived? Do you have an estimate of the number of speciation events? Those estimates seem necessary to calculate the number of expected intermediate fossils.

    I’m looking forward to seeing your calculations, and I sincerely hope you weren’t just blowing smoke.

  20. jitsak,

    An very high percentage of extant species get fossilized which leads one to believe the fossil record must contain a high percentage of the non extant species. Unless the dog ate the non extant fossils.

    This thread has been neglected and Allen MacNeill has contributed with a long comment that deserves analysis.

  21. Allen MacNeill,

    Neither speciation nor any of its proposed mechanisms are being debated.

    And I doubt that the theory of evolution expected there to be any reproductive isolation at all.

    However the Creation account does expect there to be reproductive isolation.

    Note that none of these stages is absolutely defined; rather, they integrade in what Darwin characterized as an “insensible series”.

    Which is why we wouldn’t expect to see a nested hierarchy- that “insensible series” would blur the lines of distinction required by a nested hierarchy.

  22. Allen,

    Thank you for a very cogent and logical explanation for the evolutionary process. But you said

    “Therefore, what is ultimately at issue between non-YEC ID supporters is not speciation per se nor the mechanisms by which it occurs or is reinforced, but rather whether there are “natural” limits to the degree of divergence that can take place as a result of the mechanisms that comprise the “engines of variation”.

    This is not a question that can be answered via pure theoretical (i.e. mathematical) speculation. However, compelling a model may appear, it must be tested empirically to see if it conforms to the evidence from nature. This is what evolutionary biologists do all the time, and what ID theorists seem either unable or unwilling to do. Until this situation changes (if it ever does), no reputable scientist will take ID seriously.”

    Why did you have to end it with a slam and you wonder why we slam back some times.

  23. Here is the record of fossilization

    1 – There are 43 known living orders of vertebrates and 42 have been found in the fossil record.

    2 – There are 329 living families of vertebrates and 261 have been found as fossils or about 80%. If one removes birds from this count there are 178 families of vertebrates and 156 of them have been found as fossils or 88%. The birds have only 70% fossilization.

    So the chance of all the missing links being truly missing is kind of small.

  24. jerry: There are 43 known living orders of vertebrates and 42 have been found in the fossil record.

    Orders are very broad groupings that often include thousands of species over millions of years. For instance, Carnivora diverged forty million years ago, and includes lions and tigers and bears, as well as foxes and weasels. The family Felidae alone includes everything from saber tooth tigers to your house cat. Saying that even a single fossil of Carnivora means the fossil record is relatively complete doesn’t seem warranted.

    In the human lineage, the order Primate includes monkeys, gorillas and Australopithecines. The order Hominidae alone includes orangutans and humans. Saying that even a single hominid fossil means the fossil record is relatively complete doesn’t seem warranted.

    They do all support the nested hierarhcy.

  25. Mr Jerry,

    An very high percentage of extant species get fossilized which leads one to believe the fossil record must contain a high percentage of the non extant species. Unless the dog ate the non extant fossils.

    Since most extant species are insects and microbes, I’m not sure how you justify that.

    1 – There are 43 known living orders of vertebrates and 42 have been found in the fossil record.

    2 – There are 329 living families of vertebrates and 261 have been found as fossils or about 80%.

    Ah, solved the problem by ignoring them. But still, you haven’t got down to the level of the species yet, so I’m interested in how this line of argument is going to turn out.

    According to the fount of all knowledge, Wikipedia, there are 58,000 described species of vertebrate. 10,000 are birds, and birds fossilize poorly. 1,100 are bats, and bats fossilize poorly. 28,000 are fish, and fish fossilize poorly. 6,400 are amphibians, and amphibians fossilize poorly. 45,500 out of 58,000 species are from groups that fossilize poorly. I am very interested in how you support your first claim, even restricted to vertebrates.

  26. Zachriel:

    They do all support the nested hierarhcy.

    Lineages don’t support nested hierarchies.

    Not even branching lineages.

    Orders are defined based on characteristics.

    Those who share the characteristics defined by that Order are a member of it.

    And decent still is not a defining characteristic.

    Not only that both you and Allen MacNeill have provided the reasons why a nested hierarchy is NOT predicted by descent with modification.

    Thank you.

  27. jerry

    So the chance of all the missing links being truly missing is kind of small.

    Since you haven’t responded to the refutations of this claim, can we assume that you — prisoner of reason and truth by your own account — admit to its falsity?

  28. Mac @14

    However, compelling a model may appear, it must be tested empirically to see if it conforms to the evidence from nature. This is what evolutionary biologists do all the time

    Empirically, what new functions have arisen from the aftermath of reproductive isolation? For your statement above to be accurate, please provide a list of empirically witnessed new functions.

    Only new function arising from increased genetic complexity = macroevolution. Otherwise, you are just blowing smoke.

  29. jitsak @27:

    Your argument is a little unclear, jitsak, and jerry is probably as confused as I am. Are you proposing that there are very few intermediate forms between major classifications of life?

  30. SpitfireIXA: For your statement above to be accurate, please provide a list of empirically witnessed new functions.

    As evolution can take millions of years, we wouldn’t expect to see new functions occurring very often on short time scales. Historically, we have the evolution of fins to limbs to arms to wings to fins. Or mammary glands. If you want something more recent, the evolutionary adaptation of of Galápagos finch beaks for various food sources.

    SpitfireIXA: Are you proposing that there are very few intermediate forms between major classifications of life?

    Jerry was claiming that the fossil record was reasonably complete, “so the chance of all the missing links being truly missing is kind of small.” He based this by noting that of the 43 living orders of vertebrates, 42 have been found in the fossil record. This is a fallacious argument, as noted above (#24).

  31. Zachriel @30

    As evolution can take millions of years, we wouldn’t expect to see new functions occurring very often on short time scales.

    Then you agree with me that the word “empiric” is improperly used by MacNeill and should not be allowed anywhere near Darwinism.

    Historically, we have the evolution of fins to limbs to arms to wings to fins.

    Because the examples that you provide fit better and more cleanly into an engineering decision model, they fit ID better. And we do have empiric evidence of engineering decision models.

    If you want something more recent, the evolutionary adaptation of of Galápagos finch beaks for various food sources.

    Beak traits which returned to normal size after the drought ended, resulting in no evolution. Adaptation is a conservation capability, not a demonstrated evolutionary one.

  32. Zachriel: As evolution can take millions of years, we wouldn’t expect to see new functions occurring very often on short time scales.

    SpitfireIXA: Then you agree with me that the word “empiric” is improperly used by MacNeill and should not be allowed anywhere near Darwinism.

    Not at all. This is apparently the exchange to which you are referring:

    Allen_MacNeill: However, compelling a model may appear, it must be tested empirically to see if it conforms to the evidence from nature. This is what evolutionary biologists do all the time

    SpitfireIXA: Empirically, what new functions have arisen from the aftermath of reproductive isolation? For your statement above to be accurate, please provide a list of empirically witnessed new functions.

    A scientific model which explains something doesn’t have to directly observe it. It does have to make specific and distinguishing empirical predictions.

    For instance, Einstein’s explanation of Brownian Motion depended upon the physical existence of molecules, and provided a rough estimate of their size. Brownian Motion is an empirically observable consequence of molecules, but is not a direct observation of molecules.

    Zachriel: Historically, we have the evolution of fins to limbs to arms to wings to fins.

    SpitfireIXA: Because the examples that you provide fit better and more cleanly into an engineering decision model, they fit ID better.

    They are clearly “new functions have arisen from the aftermath of reproductive isolation.” That’s what you asked for. (Or do you reject Common Descent? If so, we have to start with that.)

    SpitfireIXA: Beak traits which returned to normal size after the drought ended, resulting in no evolution.

    Not correct (the resulting populations were not the same as the original populations), but irrelevant as I was referring to the historic radiation which clearly resulted in diversification.

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