National Geographic

Evolution in Color: From Peppered Moths to Walking Sticks

The color of an animal can determine whether it lives or dies. If it’s easily spotted by predators, it may well become a meal. Hidden nicely against its background, an animal can escape its enemies for another day.

The particular colors on an animals are determined partly by the genes its gets from its parents. That means that genes that hide animals can spread thanks to natural selection, leading to the evolution of exquisite camouflage. But that’s not to say that the animal kingdom has settled on a perfect, fixed palette. You can find mismatched individuals. Over the course of generations, a whole population can flicker between mismatched and well-matched.

White form of peppered moth. Via Wikipedia

White form of peppered moth. Via Wikipedia

Melanic form of peppered moth. Via Wikipedia

Melanic form of peppered moth. Via Wikipedia

The most famous example of mismatched colors first came to light in the 1950s. Coal smoke had darkened England’s trees, so that light pepper moths, once blended nicely against bark, now stood out against the smudgy background. A dark form of peppered moths, once rare, became common. Researchers suspected that natural selection was the reason why, and they tested that idea by putting dark and light moth models on trees. Birds quickly attacked the mismatched ones, as had been predicted.

The photos from these experiments became a staple of textbooks. But doubts arose about the research. Real peppered moths often don’t sit on tree trunks with wings extended, for example. Creationists called the whole phenomenon a fraud and a reason to question evolution itself.

leeds moths

Decline of dark peppered moths around Leeds, England. From Thompson, “Relentless Evolution”

But the evidence in favor of natural selection on peppered moths continued to accumulate. For one thing, Britain and other countries cleaned up their air in the late 1900s, and trees went from dark to light. Now natural selection’s balance shifted: black became a liability. And, as you’d predict, the dark moths went from common back to rare again.

To see if predators were the instrument of their disappearance, biologist Michael Majerus launched a massive study in 2001. He died before he could publish the experiment; it only came out last year, completed by some of his fellow scientists, in Biology Letters. (It’s free to read.)

Majerus released 4864 moths, some dark and some light, and then observed how they landed on trees and how likely they were to escape being eaten by birds. Each day, he found, dark moths were nine percent less likely to survive. Since the moths only live for a few days in the wild anyway, that difference was enough to quickly drive dark moths from common to rare if they didn’t match their background.

The story of the peppered moth is striking, but it’s also a story of civilization. As we humans developed different ways of producing energy–first dirty, then clean–we altered the environment in which animals evolve. Their colors tracked our history. The story of the peppered moth still leaves us to wonder about the evolution of color in the natural world, beyond the dark Satanic mills.

Thousands of miles away from England’s peppered moths, a species of walking stick insects called Timema cristinae lives in the hills of southern California. A new study shows that they feel the pressure of evolution on their color, too. In fact, the evolution of color is so powerful that it doesn’t just affect the walking sticks. It affects the diversity of their entire ecosystem.

The new study, carried out by Patrik Nosil of the University of Sheffield and his colleagues, took place in the hills outside of Santa Barbara. When the scientists beat the bushes in those hills, they find Timema cristinae insects with two color patterns. Some are solid green, while others have white stripes running up their bodies. Depending on the bush they inspect, they may find mostly green bugs, mostly striped ones, or a mix of the two.

A striped form of walking stick (A) is often found on narrow-leafed bushes. A solid green one is often found on wide-leafed bushes. From Farkas et al 2013, Current Biology

A striped form of walking stick (A) is often found on narrow-leafed bushes. A solid green one is often found on wide-leafed bushes. From Farkas et al 2013, Current Biology. Illustration by Rosa Ribas

It’s no surprise that they can find a mix of the insects. Walking sticks don’t have wings, so they live mostly on a single bush their whole life. But when a new generation of walking sticks emerges, some of the insects will disperse to a different bush.

But why are there two such different forms in the same species? The ecologist Cristina Sandoval first recognized that the answer had to do with the bushes that the walking sticks live on. Each pattern may do a good job of protecting a walking stick from birds–just as long as it is living on the right bush.

One species of bush that the insects live on has thick green leaves. A solid green walking stick blends right in with that foliage. Another species of bush grows needle-like leaves. The white stripes on some walking sticks divides into green strips, making them look like thin leaves.

A striped walking stick hides among thin leaves. Photo by Mortiz Muschick

A striped walking stick hides among thin leaves. Photo by Mortiz Muschick

If the walking sticks get on the wrong bush, however, they lose their disguise. Against the thin leaves, the solid green insects leap out. Against the big leaves, the pale stripe of the other walking sticks looks out of place.

Nosil and his colleagues have been studying how these different kinds of camouflage play out in the California hills. A map of the insects and the bushes bears out this idea. In places where there are lots of thick-leaves bushes, the walking sticks are mostly solid green. In places where the thin-leaved bushes dominate, most of the insects have a white stripe. But if a thick-leafed bush is surrounded by thin-leaved ones, it will have many mismatched insects. That’s a pattern you’d expect from the combination of bird-driven natural selection and insects moving among neighboring bushes.

To put this idea to a thorough test, Nosil, his student Tim Farkas, and their colleagues studied 186 bushes in the California hills. They caught every walking stick insect on the bushes to do a population census. They found that when the insects were well-matched to the bush, their numbers were high. When they were badly matched, the population was much lower. That pattern makes sense if the birds are picking off the insects that are standing out against the bushes.

Nosil and his colleagues then altered the populations of walking sticks on each bush. To some bushes, they added 200 well-matched insects. To others, they added 200 mismatched ones. They waited a month–during which time the insects fed on the bushes and birds fed on the insects–and then returned to see how things had gone.

On the bushes with mismatched insects, the populations were half what Nosil found on the bushes with the well-matched ones. Birds presumably swooped in and feasted on the easy-to-spot walking sticks.

But the effects did not stop there. Instead, they rippled out to other species. Nosil and his colleagues didn’t just count up the walking sticks on the bushes–they also tallied the caterpillars, spiders and other invertebrates. And they found a stark change in their numbers too. On the bushes with mismatched walking sticks, the other species dropped by half as well.

Not only did the numbers go down for all the species, but some species disappeared altogether from bushes. On bushes with extra camouflaged walking sticks, on the other hand, other species thrived.

Nosil and his colleagues also found that they altered the bushes themselves with the experiment. Walking sticks chew on leaves, and so it stands to reason that bushes with fewer walking sticks ended up getting chewed less. But the scientists wondered how much damage the plants suffered from other insects, which pierce or suck the plants instead of chewing them. They found that bushes full of mismatched walking sticks suffered less of this kind of damage, too. In other words, the bushes benefited from mismatched walking sticks because they wiped out all the species feeding on them.

It was surprising that getting rid of walking sticks would also lead to the devastation of other species. The disappearance of walking sticks could have led to an increase in other animals, because there would be less competition for food. To understand why this was’t happening, Nosil repeated the experiment all over again, but with a twist. He and his colleagues put chicken wire over some bushes so that birds couldn’t get to them.

On the bushes that were left unprotected, the scientists found the same result: walking sticks and other species were wiped out when the walking sticks were mismatched, and the bushes benefited. But the chicken wire wiped out those results on the enclosed bushes. There was no difference between bushes with mismatched and well-matched walking sticks.

That experiment established that it’s the birds that are responsible for all the effects the scientists had seen. They were attracted to the mismatched walking sticks, because walking sticks are so abundant on the bushes. And then stayed on the bushes to feast on the other prey. When the birds cleaned off all the animals from the bushes, they protected the bushes.

Adding extra walking sticks to bushes mirrors the different combinations of walking insects you can find in nature. Nosil argues that as evolution acts on the walking sticks, it shapes the diversity of other species in the hills of California.  To understand why there are a given number of species in one place, scientists may need to understand the rapid evolution going on there. The power of color evolution, it appears, reaches far beyond our eye.

[10/10: A few corrections, including name-checking Sandoval]

There are 32 Comments. Add Yours.

  1. Paul Braterman
    October 9, 2013

    The peppered moth story shows the creationists at their most deceptive, still repeating Wells’s long refuted attacks on the work: http://www.3quarksdaily.com/3quarksdaily/2013/08/creationism-as-conspiracy-theory-the-case-of-the-peppered-moth.html

  2. James V. Kohl
    October 9, 2013

    page 196: “…natural selection is an evolutionary process initiated by mutation.”

    As indicated in that quote from the book “Mutation-driven evolution,” the peppered moth was not simply a model organism for natural selection via predation, it was a model of how a mutation or accumulated mutations supposedly led to the color change that enabled natural selection via predation.

    “A greater understanding of the peppered moth’s genetics will “complete the package” of research on “the best example of adaptation involving natural selection that we have”, says Bruce Grant, a retired population geneticist…”

    His comment was echoed: “Robert Reed, an evolutionary developmental biologist at the University of California… said: ‘The fact that the carbonaria mutation maps to the same region as butterfly wing pattern genes is amazing.

    What is “amazing” about the “best example of adaptation involving natural selection that we have” is that no one attempted to explain how the mutation that initiated the natural selection via predation came and went. It arrived with the pollution and somehow effected what was claimed to be a population-wide color change in a moth species. But the moth species changed color again when the pollution was controlled. The mutation-initiated natural selection via predation that comes and goes with color changes defies explanation via any current perspective on mutation-driven evolution, unless a a second mutation caused the change back to the original color.

    Comments like the one from Paul Braterman do nothing to resolve issues that he seems to think pit the creationists against evolutionary theorists. I could just as readily claim that the theorists are being deliberately deceptive by taking natural selection out of the context of mutations theory. They make it appear that natural selection automagically occurs via predation for a mutation that comes and goes with pollution.

    But there’s no point in attacking the theorists. They’re convinced that natural selection automagically occurs, or that it’s mutation-initiated, or both, or neither, depending on what day it is and what model organism they’re using for their theory. They may not be deceptive at all, just confused.

    [CZ: Scientists have done a lot of research on the mutations involved in variations in color. They have identified the gene involved in pepper moth color; one version makes it white, another makes it black. In 2011, scientists determined that a single mutation of recent origin is responsible for "industrial melanism." The abstract reads as follows:

    "The rapid spread of a novel black form (known as carbonaria) of the peppered moth Biston betularia in 19th-century Britain is a textbook example of how an altered environment may produce morphological adaptation through genetic change. However, the underlying genetic basis of the difference between the wild-type (light-colored) and carbonaria forms has remained unknown. We have genetically mapped the carbonaria morph to a 200-kilobase region orthologous to a segment of silkworm chromosome 17 and show that there is only one core sequence variant associated with the carbonaria morph, carrying a signature of recent strong selection. The carbonaria region coincides with major wing-patterning loci in other lepidopteran systems, suggesting the existence of basal color-patterning regulators in this region."]

    • Paul Braterman
      October 10, 2013

      ” unless a a second mutation caused the change back to the original color”

      Oh dear! James Kohl’s “problem” was resolved by JBS Haldane in 1924. Dark is dominant, pale recessive, the extinction of pale is therefore vanishingly slow, so it never totally disappeared, and no “second mutation” was needed to restore it.

  3. James V. Kohl
    October 10, 2013

    Thanks CZ. It will take me a while longer to respond to you; this is for Paul.

    My ‘problem’ is Haldane’s assumptions in the context of cause and effect. Since no experimental evidence ever supported his assumptions, theorists were left with an idea that was never scientifically substantiated. Now, even Braterman may realize that mutation-driven evolution is a foolish idea. It requires one mutation to be fixed for natural selection to occur, and he just told us that the mutation was not fixed.

    Obviously, a controlling factor that prevents the fixation of new alleles should have been included in the theory of mutation-initiated natural selection. That’s the problem, and it is certainly not my problem. It is, however, a problem for those who accept the first idea that comes along and incorporate it into their knowledge base and beliefs without questioning whether there is model for that.

    • Paul Braterman
      October 10, 2013

      I assume that by “fixed”, James means 100%. The dark form never reached 100% (observational data), nor was it expected to (Haldane’s paper). Relative abundance (measured by population count) fluctuated in response to evolutionary pressure (measured, in Majerus’ work designed to avoid the pitfalls in Kettlewell’s, by direct observation of predation). Surely we can agree on that much, and I cannot envisage a clearer vindication of the original claim.

      Evolution has long since been defined as a change in the *relative abundances* of alleles in a population. James’s additional requirement that one kind of mutated allele be “fixed” is an arbitrary addition of his own.

      The “controlling factor that prevents the fixation of new alleles”, which is what James says I should be demanding, is what Haldane predicted in 1924; the slow rate of final disappearance of an unfavourable recessive (see my first comment). This was not an input into his model, but a mathematical deduction from it, experimentally vindicated by the survival of a reservoir of pale alleles until, from the 1950s, the balance of advantage reverted towards its pre-industrial value.

      Twice is enough. I’m sure James will remain unconvinced, but I’m not going to say it all over again for a third time.

  4. James V. Kohl
    October 10, 2013

    Thanks Dr. Braterman. Let’s stop the assumptions! No disrespect intended.

    Anyone with your level of expertise should realize the controlling factor that prevents fixation of mutated new alleles is the nutrient-dependent physiology of reproduction. It was not addressed by Haldane, and it is considered by biologists — and especially physiologists, like Denis Noble, to be the feature that damns mutation-initiated natural selection to its ultimate obscurity. See for example: Physiology is rocking the foundations of evolutionary biology. http://ep.physoc.org/content/early/2013/04/12/expphysiol.2012.071134.abstract

    Re: your mention that “Evolution has long since been defined as a change in the *relative abundances* of alleles in a population.” Please help us to put that definition into the context of WHAT is mutation-initiated and naturally selected and HOW it is naturally selected.

    No need to repeat anything as if we do not understand each other. Simple answers to what is selected and how it is selected can be found from experiments in every species. Is there a theory you would like to help others compare in the context of experimental results?

  5. Troll Wrangler
    October 10, 2013

    James just stop. You just don’t understand what you are reading. Why do people keep making this mistake:

    “What is “amazing” about the “best example of adaptation involving natural selection that we have” is that no one attempted to explain how the mutation that initiated the natural selection via predation came and went. It arrived with the pollution and somehow effected what was claimed to be a population-wide color change in a moth species. But the moth species changed color again when the pollution was controlled. The mutation-initiated natural selection via predation that comes and goes with color changes defies explanation via any current perspective on mutation-driven evolution, unless a a second mutation caused the change back to the original color.”

    You are just confused about the basic definitions of evolution, selection and mutation. Go read the background info before pretending to have some sort of meta-insight. It’s ridiculous that so many people keep floating this moronic argument when it’s been refuted over and over and over and over. James, mutations are always occurring. Every time a cell divides mutations occur at some rate. This has been shown experimentally many times. Most of these either have no effect or are deleterious, only a rare few mutations ever provide some type of advantage. Why is that hard to understand? Mutations always occur at random across every genome. Selection can then act to filter these. There is no pre-directed mutations that selection requires, that has also been demonstrated over and over again, try google scholar.

  6. James V. Kohl
    October 10, 2013

    Transposable Elements: [are] Targets for Early Nutritional Effects on Epigenetic Gene Regulation. They are the Transposable Elements [placed into the context of], Epigenetics, and Genome Evolution in the 2012 AAAS presidential address, which extended from plants to moths and to butterflies the concept of Transposable element evolution in Heliconius [that] suggests genome diversity within Lepidoptera is controlled by the metabolism of nutrients to species-specific pheromones. Pheromones, as many people may already know, control the nutrient-dependent physiology of reproduction, which is how adaptive evolution is controlled in species from microbes to man.

    I just incorporated the titles from three citations to construct a somewhat cohesive statement that accurately reflects what is currently known about the molecular epigenetics of adaptive evolution. That was easy! I merely ignored mutations “theory” and classic ‘examples’ of mutation-initiated natural selection for color like the peppered moth. Instead, as I always have, I focused the biological facts that evolutionary theorists have ignored. For examples of those facts, see the section on molecular epigenetics in our 1996 Hormones and Behavior review article: From Fertilization to Adult Sexual Behavior and my 2013 monograph Nutrient-dependent/pheromone-controlled adaptive evolution: a model.

    In the 2013 monograph I included this example, among examples from nematodes, other insects, other mammals, and a human population: “In Ostrinia moth species, substitution of a critical amino acid is sufficient to create a new pheromone blend (Lassance et al., 2013). In the ‘peppered moth’ example of rapid response to human-induced environmental changes, which were heretofore considered to be driven by selective predation, some evidence now suggests the migration pattern of 2 km per evening is consistent with the male moth’s ability to detect the nutrient-dependent pheromones of the female from 2 km upwind (see for review Cook & Saccheri, 2013).”

    No experimental evidence suggests that mutations are fixed in the DNA of any organized genome of any species that has adaptively evolved. No experimental evidence suggests that natural selection for morphogenesis occurs, except via the association of phenotypic expression, including color changes, with selection of nutrients that metabolize to species-specific pheromones.

    If not for successful attempts by experts like Dr. Braterman to continue to tout their theories via obfuscation of cause and effect, or by cursing those anyone who doesn’t agree with the label of creationist, scientific progress would be decades further ahead than what most people can imagine — if only because they, too, were taught that mutations initiated natural selection that led to the diversification of species from microbes to man.

    Carl Zimmer admitted elsewhere that he can merely take what the experts say and make it easier for more people to understand. What must now be understood is what this phrase means: “The carbonaria region coincides with major wing-patterning loci in other lepidopteran systems, suggesting the existence of basal color-patterning regulators in this region.”

    It means the presence of color-patterning regulators in that region is nutrient-dependent and pheromone-controlled. That means that color-patterning is not mutation-initiated and that color is not selected via predation. Color is selected, like all phenotypic variation in morphogenesis is selected. Color is selected via its associated with olfactory/pheromonal input and the de novo creation of olfactory receptor genes, not mutations.

  7. Troll Wrangler
    October 10, 2013

    Gotta love when some “alternative” internet scientist genius can refute everyones’ experiments and conclusions.

    “Color is selected, like all phenotypic variation in morphogenesis is selected. Color is selected via its associated with olfactory/pheromonal input and the de novo creation of olfactory receptor genes, not mutations.”

    That makes zero sense. This a is a gold mine of some of the most absurd speculation I’ve seen yet.

    Clearly you just don’t understand the vocabulary you are trying to use, much less the nuances of the experiments in the papers you may have tried to read.

    Start with taking a deep breath and going back to the basics about mutations. They occur all the time and are mostly deleterious. That’s why people get cancer, that’s where variation comes from, you can actually measure it in real time in the lab now–see google for numerous examples. There is no pre planning for fitness and there is no cause of SPECIFIC mutations by selection. You’re confused about what the definition of selection is. Although the rate of these random mutations is itself a trait that is selected on, for example: http://twileshare.com/bbwn

  8. Jillian Lowe
    October 10, 2013

    I’m proud like a mama bear!

  9. Roy Niles
    October 11, 2013

    Have you people never heard of adaptive mutation where the organism takes advantage of randomness and not the other way around. Complex behaviors aren’t acquired by accidents, they are the organism’s intelligent responses to accidents.
    How do they then become heritable? Read stuff by James Shapiro and Steven Rose. And note that Denis Noble is now a Shapiro fan.

  10. James V. Kohl
    October 11, 2013

    I wrote: “I just incorporated the titles from three citations to construct a somewhat cohesive statement that accurately reflects what is currently known about the molecular epigenetics of adaptive evolution. That was easy! I merely ignored mutations “theory” and classic ‘examples’ of mutation-initiated natural selection for color like the peppered moth. Instead, as I always have, I focused the biological facts that evolutionary theorists have ignored.”

    See, for example: http://www.sciencemag.org/content/338/6108/758.short

    I welcome discussion of transposable elements — as linked across species by the former president of the AAAS — with anyone who is not an anonymous fool, and hope that Dr. Braterman will respond.

  11. James V. Kohl
    October 12, 2013

    “Adaptive mutation?” Does Shapiro use that term? I thought his book was a refutation of mutation-initiated natural selection as represented in Nei’s book: Mutation-Driven Evolution.

    In any case, I have a comment awaiting moderation about the fact that Transposable elements are the most likely cause of color variation in moths and butterflies. It would be unusual if the same molecular mechanisms of color changes were not conserved across species. So, where do adaptive mutations enter the picture? Is there a model organism that exemplifies how adaptive mutations cause color changes?

  12. Roy Niles
    October 12, 2013

    Model organism as to how adaptive mutation causes color changes? Try cephalopods, where some of them have adapted their color systems to change “at will” to make them less visible to predators and prey in a particular environment. These are intelligently constructed systems that can hardly have come about where that intelligence was inserted by accident.

  13. James V. Kohl
    October 12, 2013

    What mutation-initated changes enable natural selection for color changes in cephalopods? Supposedly, most of them are color blind. For comparison, see in Shapiro’s book: “Signaling from the cell surface to the genome: Pheromone response in the sexually aroused yeast cell.”

    In our 1996 Hormones and Behavior review article we noted that this model organism exemplified self vs non-self recognition, which is obviously nutrient-dependent and pheromone-controlled as is the adaptive evolution of sex differences and morphological differences, including differences in color, in all species from the advent of such differences in yeasts.

    Most yeasts are probably not colored or color-blind like most cephalopods, however. And yeasts don’t have eyes, like many other species that have, nevertheless, adaptively evolved.

    Any attempt to use cephalopods as model organisms of adaptive mutations
    jumps from unicellular organisms with no eyes to color-blind multicellular organisms.

    Note to others: Roy Niles challenges me to intelligently respond to some of the most uninformed comments I have ever seen anyone attempt to enter into discussion. Denis Noble is a Shapiro fan because he understands the physiology of nutrient-dependent pheromone-controlled reproduction that links microbes to man.

    Niles wants us to “try cephalopods.” Try them for what?

  14. Roy Niles
    October 12, 2013

    Thank you, Kohl, for that antagonistic response, and just as I was about to commend you for citing that excellent paper from Nina Fedoroff. So of course if you are looking for a fight there’s no reason for me to point out that plants and animals have evolutionary purposes in common even if they use their intelligent capacities differently – just as different species in the animal world alone must do.
    You’re obviously here to promote a theory that no-one outside of yourself supports, while my purpose is to support the very theoretic progress in the field that Federoff has described in that cited paper.
    So good luck with that, And by the way I’ve corresponded with Denis Noble directly, and his reasons for his recent conversion as a Shapiro fan had nothing to do with your silly prattle about pheromone-controlled reproduction.

  15. James V. Kohl
    October 12, 2013

    You’re welcome, Niles. Transposable elements link plants and animals. Mutation-initiated natural selection does not.

    Please support your comment about my “silly prattle” by telling us about an animal species that does not exemplify nutrient-dependent pheromone-controlled adaptive evolution. Color changes in Cephalopods didn’t work for you, did they?

    I’m also certain that you first learned about transposable elements from me, and have no idea of their across-kingdoms and across-species implications. For contrast, Shapiro and Noble already know that the nutrient-dependent alternative splicings that clearly link the epigenetic landscape to the physical landscape of DNA must be controlled — even if they have not yet realized that the alternative splicings are controlled by nutrient-dependent pheromone-production as detailed in my model, which includes the details in two award-winning publications. What made you think that no-one outside myself supports my model (which is not a theory)?

    Without the control of alternative splicings mutation-initiated natural selection could occur, I guess. But what is being selected, and how are some mutations not allowed to progress to cancers?

  16. Roy Niles
    October 12, 2013

    You say “mutation-initiated natural selection does not” link plants and animals? Shapiro would tell you that bacteria evolved by the adaptive mutation process to become important elements of the functional structures of every known plant and animal.
    And if you think he or Noble or anyone else supports your “model” you’re
    welcome to think so. I personally think that nobody that I know of thinks so.

  17. Roy Niles
    October 12, 2013

    By the way, (and quoting from Wikipedia) Lynn Margulis formulated an endosymbiotic theory to explain how symbiotic relationships between organisms of often different phyla or kingdoms are the driving force of evolution. Genetic variation is proposed to occur mainly as a result of transfer of nuclear information between bacterial cells or viruses and eukaryotic cells.
    No reference was made there or in a number of her books that I’ve read, to nutrient dependent pheromones controlling any part of the process.

  18. Roy Niles
    October 12, 2013

    I see I’ve been put back into the “moderation needed” status. Oh well.

  19. James V. Kohl
    October 12, 2013

    I incorporated the late Lynn Margulis’ work into my model, and have specifically mentioned the support the model has received for publications in “Neuroendocrinology Letters” and in the “Journal of Psychology & Human Sexuality,” which led to the following statement in a book by neuroanatomist Simon LeVay:

    “This model is attractive in that it solves the “binding problem” of sexual attraction. By that I mean the problem of why all the different features of men or women (visual appearance and feel of face, body, and genitals; voice quality, smell; personality and behavior, etc.) attract people as a more or less coherent package representing one sex, rather than as an arbitrary collage of male and female characteristics. If all these characteristics come to be attractive because they were experienced in association with a male- or female-specific pheromone, then they will naturally go together even in the absence of complex genetically coded instructions.”

    You, on the other hand, are one of the antagonists whose ridiculous comments never address the content of anything I have published. You refer to my works as if the model was a theory, and offer us the color-blind cephalopod as an example of something involved in the nutrient-dependent pheromone-controlled morphogenesis of color.

    What are you doing here, Roy? Others may want to engage in intelligent discussion of biological facts. You write: “Shapiro would tell you that bacteria evolved by the adaptive mutation process…”

    In the first part of his book he brings up the role of pheromones in yeasts. I can’t recall if he mentions that pheromones control reproduction in bacteria, but if he did not, it’s probably because everyone knows that except you.

    Everyone but you also knows that the adaptive evolution of bacteria is nutrient-dependent. Simply put, you appear to be so simple-minded that you are unable to recognize what virtually everyone else on this planet knows: organisms must eat, and species must reproduce and there is no experimental evidence that mutation-initiated natural selection is involved in what is clearly the nutrient-dependent physiology of pheromone-controlled adaptive evolution.

  20. Roy Niles
    October 12, 2013

    My response to you, Kohl, explaining how octopi and other cephalopods can distinguish differences in color has been held up by the moderator, and I expect this response will be held up as well. But in any case, we all know that biological systems need energy, but referring to that process as “eating” is where the simple mindedness actually reveals itself. Shapiro has not mentioned pheromones as having had control of the energy absorbance process of bacteria, and especially not as having played a determinant role in their evolution. And neither did Margulis, in spite of your attempt to make it seem she would have if she’d thought to do so.
    Here’s what Wikipedia says about their early use:
    “There are physical limits on the practical size of organisms employing pheromones, because at small sizes pheromone diffuses away from the source organism faster than it can be produced, and a sensible concentration accumulates too slowly to be useful. So bacteria are too small to use pheromones as sex attractants on an individual basis but do use them to determine the local population density of similar organisms and control behaviors that take more time to execute (quorum sensing or to promote Natural competence for Transformation (genetics), i.e. sexual gene transfer). In similar manner, the simple animals rotifers are, it appears, also too small for females to lay down a useful trail, but in the slightly larger copepods the female leaves a trail that the male can follow.”

  21. Roy Niles
    October 12, 2013

    Carl, Please explain to me why that second attempt at making a perfectly reasonable comment has been put on moderation status again while clearly insulting comments from Kohl to me are sliding through?

  22. Roy Niles
    October 12, 2013

    @Kohl: >Color is selected, like all phenotypic variation in morphogenesis is selected. Color is selected via its associated with olfactory/pheromonal input and the de novo creation of olfactory receptor genes, not mutations.<
    So do plants have olfactory reception genes? And if so, how has it been determined that color selection is related to olfactory/phenomenal input that these genes are somehow facilitating?

  23. James V. Kohl
    October 12, 2013

    Three responses in a row from Niles have failed to address any aspect of the evidence I have already offered on color changes and then added on color changes. I hope that others can see why I had hopes for intelligent discussion of color changes in animals, but all hopes have been dashed by this buffoon who now wants me to tell him everything I know about botany.

  24. Roy Niles
    October 12, 2013

    Meaning, Kohl, that you don’t have any evidence to back up what you said about color as it evolved from bacterial pheromones to those of insects and yet apparently was not a process transferable to the plants that also evolved from bacterial ancestry? All you have left is argument from insult. Buffoonery indeed.

  25. James V. Kohl
    October 12, 2013

    What I have is a model of nutrient-dependent pheromone-controlled adaptive evolution and the model includes morphogenesis, which includes color changes! http://www.socioaffectiveneuroscipsychol.net/index.php/snp/article/view/20553 You’re not very bright, are you Roy?

  26. Roy Niles
    October 13, 2013

    Kohl, I’m an expert when it comes to spotting con artists and in your attempt to sell your perfumery products you’ve come up with one of the most transparent cons I’ve yet to see. You present the model of a thesis as if the actual evidence and arguments that might support a thesis were a given, as otherwise the model would not have been fabricated by such an honest broker as yourself.
    Nobody anywhere in the scientific community, except for the dupe you used to co-author your manifests, buys your model or the theory that it’s supposed to represent. But you won’t give up since once a con gets under way, there’s no way you can or want to stop it as long as you products for sale that depend on maintaining that front. There’s a sucker born out there every minute, but very few of them are bona fide scientists, as you have clearly learned. But you’re not after them in any case, are you. You’re after any sucker who happens to read these public articles.

  27. Roy Niles
    October 13, 2013

    From your proffered article which in no sense is a scientific study:
    “Conflict of interest and funding
    The author has not received any funding or benefits from
    industry or elsewhere to conduct this study.”
    Apparently you forgot to tell them that you run a business that both manufactures and sells perfumery products.

  28. Roy Niles
    October 13, 2013

    From your proffered article which in no sense is a scientific study:
    “Conflict of interest and funding
    The author has not received any funding or benefits from
    industry or elsewhere to conduct this study.”
    Apparently you forgot to tell them that you run a business that both manufactures and sells perfumery products.

  29. Roy Niles
    October 13, 2013

    From your proffered article which in no sense is a scientific study:
    “Conflict of interest and funding
    The author has not received any funding or benefits from
    industry or elsewhere to conduct this study.”
    Apparently you forgot to tell them that you run a business that both manufactures and sells perfumery products.

  30. Carl Zimmer
    October 13, 2013

    Roy and James, you’ve turned this comment thread into your own personal cage match. You have made your points repeatedly, and now are just calling each other names. I’m calling game over. My blog, my rules. You are welcome to continue your dispute on your own blog.

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