Darwin’s finches not a good example of Darwinian evolution?

_{Denyse O'Leary

February 12, 2015

Darwinism, Evolution, Intelligent Design, News}

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Yes, we are discussing the icon of Darwinism that you heard about at school. They interbreed so much, it is hard to know how much they are separate species. From the BBC

The most extensive genetic study ever conducted of Darwin’s finches, from the Galapagos Islands, has revealed a messy family tree with a surprising level of interbreeding between species.

It also suggests that changes in one particular gene triggered the wide variation seen in their beak shapes.

…

The study also revealed a surprisingly large amount of “gene flow” between the branches of the family.

This indicates that the species have continued to interbreed or hybridise, after diversifying when they first arrived on the islands.

…

“It’s been observed that the species of Darwin’s finches sometimes hybridise – Peter and Rosemary Grant have seen that during their fieldwork,” Prof Andersson told the BBC.

“But it’s difficult to say what the long-term evolutionary significance of that is. What does it contribute?”

What it contributes is that one would be hard pressed to show that there is any evolution going on, in the face of this much hybridization. A friend sends along a key point from the Discussion of the paywalled Nature paper:

Evidence of introgressive hybridization, which has been documented as a contemporary process, is found throughout the radiation. Hybridization has given rise to species of mixed ancestry, in the past (this study) and the present [30]. It has influenced the evolution of a key phenotypic trait: beak shape. Similar introgressive hybridization affecting an adaptive trait (mimicry) has been described in Heliconius butterflies [32]. The degree of continuity between historical and contemporary evolution is unexpected because introgressive hybridization plays no part in traditional accounts of adaptive radiations of animals [1, 2]. For young radiations it complements the better-known role of natural selection.

In short, Darwin’s finches are not a very good schoolbook illustration of the neo-Darwinian synthesis (Darwinism). How does one sort out what is Darwinism (natural selection acting on random mutation) and what is hybridization? Here’s the abstract:

Darwin’s finches, inhabiting the Galápagos archipelago and Cocos Island, constitute an iconic model for studies of speciation and adaptive evolution. Here we report the results of whole-genome re-sequencing of 120 individuals representing all of the Darwin’s finch species and two close relatives. Phylogenetic analysis reveals important discrepancies with the phenotype-based taxonomy. We find extensive evidence for interspecific gene flow throughout the radiation. Hybridization has given rise to species of mixed ancestry. A 240 kilobase haplotype encompassing the ALX1 gene that encodes a transcription factor affecting craniofacial development is strongly associated with beak shape diversity across Darwin’s finch species as well as within the medium ground finch (Geospiza fortis), a species that has undergone rapid evolution of beak shape in response to environmental changes. The ALX1 haplotype has contributed to diversification of beak shapes among the Darwin’s finches and, thereby, to an expanded utilization of food resources. (paywall)

But we will probably see the finches in the schoolbooks anyway, because Darwin’s name is, like, a brand. There is Darwin Day, there isn’t Hybrid Day.

It’s a brand lots of people have invested lots of time and money in. They won’t let that go to waste. Let the spin begin!

Follow UD News at Twitter! This is what they used to think and may well continue to say:

Comments

Zac says and still can’t describe the ‘ideal wolf form’, I say, You did not ask me to describe the ideal wolf form. If you would have asked I would have pointed you to something like this from here http://en.wikipedia.org/wiki/Gray_wolf quote: grey wolf, the largest extant member of its family, with males averaging 43–45 kg (95–99 lb), and females 36–38.5 kg (79–85 lb)like the red wolf, it is distinguished from other Canis species by its larger size and less pointed features, particularly on the ears and muzzle.Its winter fur is long and bushy, and predominantly a mottled gray in color, although nearly pure white, red, or brown to black also occur end quote: you say, can’t tell us whether a grey wolf or a coyote is closer to the ‘ideal wolf form’. I say, I happen to live in an area with two different "types" of coyote one is very wolf like and the other is closer to the western coyote type. I need to see the actual coyotes to tell you which type they are. Once I see an individual I can easily tell you which type it is. This is not rocket science. What I can't tell you is which type we are talking about just by hearing you detail a supposed genealogical relationship. You say, and can’t tell us whether a grey wolf or a coyote is closer to the ‘ideal wolf form’. I say, I can, it's easy. I just need to see the individual in question. I can't do it based only your use of terms derived from a definition of species that is completely unrelated to the definition I'm using. You say, It’s meaningless poppycock unless you can take cases and apply them. I say, I spend every day applying the old approach to actual cases. It's what we humans naturally do. I do it every time I look out the window of my car and see a canine and say to those with me "look at that coyote" You do the same thing all the time. The approach only breaks down when you try to shoehorn population groupings based on theoretical mating compatibility. you say You frequently redefining terminology, and think that constitutes an argument. I say, This is not an argument. I'm simply pointing out why there is a "species problem" at the heart of your approach that will not go away. It is your side that is redefining accepted terminology. Linnaeus concept of species is not the same as Darwin's it is as simple as that. You can't change the definition and expect the system to work. That is exactly what we have found for 150 years the finches are just the latest example Isn't time we tried a different way. peacefifthmonarchyman_{February 15, 2015
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fifthmonarchyman: Here we go again. If you plot traits of wolves and coyotes, they will tend to cluster into two groups. These clusters are what biologists call species. fifthmonarchyman: It depends on which particular individual you are talking about. Oh gee whiz. Go to the zoo or something. http://westernwildlife.org/wp-content/uploads/2012/04/WolfCoyoteComparison.jpg fifthmonarchyman: I can’t tell you which of two shapes is closer to the ideal circle until I actually see the shapes in question. Show me the actual shapes and I can tell where exactly where they diverge from the Ideal. Oh gee whiz. Go to the zoo or something. http://westernwildlife.org/wp-content/uploads/2012/04/WolfCoyoteComparison.jpg fifthmonarchyman: You seem to think that by probing you will be able to find a weakness in the old approach. The fact is the old approach has been tested and tried for millennia and it has stood the test of time Oh gee whiz. So you say you've been working on the problem for thousands of years, and still can't describe the 'ideal wolf form', and can't tell us whether a grey wolf or a coyote is closer to the 'ideal wolf form'. It's meaningless poppycock unless you can take cases and apply them. fifthmonarchyman: It only falters when you try to shoehorn Darwin’s new definition into the old framework. Darwin used standard delineation of species, the phenetic species concept that places Canis lupus (designated in 1853 by Carl Linnaeus) and Canis latrans (designated in 1820 by Thomas Say) into different species. Note that the classification of wolf and coyote as separate species occurred before Darwin's theory, so don't keep saying it was Darwin who changed the delineation. fifthmonarchyman: You seem to think that by probing you will be able to find a weakness in the old approach. You frequently redefining terminology, and think that constitutes an argument. At least most creationists use the term 'kind', and don't conflate it with the biological classification of species.Zachriel_{February 15, 2015
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zac asks Are you saying that coyotes and wolves are the same species? I'm say, Ive mentioned the Y axis several times. Here we go again. Coyotes and wolves share some features so they are related at lower levels of the Axis. The same way circles and ovals and various other ellipses are related. But as we move up the axis we reach a point that these entities diverge. As we move up the Y-axis circles diverge from ovals and wolves diverge from coyotes If we move even further up the Y-axis eastern wolves diverge from Grey wolves and western coyotes diverge from eastern coyotes. This is nothing but the taxonomic classification system that Linnaeus worked to standardize. You say. Is a coyote closer or farther from the ideal than the gray wolf? I say, It depends on which particular individual you are talking about. I can't tell you which of two shapes is closer to the ideal circle until I actually see the shapes in question. Show me the actual shapes and I can tell where exactly they diverge from the Ideal. You seem to think that by probing you will be able to find a weakness in the old approach. The fact is the old approach has been tested and tried for millennia and it has stood the test of time, It only falters when you try to shoehorn Darwin's new definition into the old framework. using a system based on one definition does not work for groupings based on an unrelated definition. Big surprise. peacefifthmonarchyman_{February 15, 2015
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Zachriel's position cannot account for wolves, coyotes, nor dogs. And that has Zachriel very upset.Joe_{February 15, 2015
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fifthmonarchyman: In the same way coyotes and dogs are wolfs to the extant that they correspond to the ideal wolf Are you saying that coyotes and wolves are the same species? Is a coyote closer or farther from the ideal than the gray wolf? fifthmonarchyman: The standard definition is subject to any number of ad hoc qualifications and aditions yet it still is subject to endless controversy among biologists. Your claim was that Darwin changed how we delineated species, but then and now, coyotes and wolves are different species.Zachriel_{February 15, 2015
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Zac says Are dogs of the wolf species? Are coyotes of the wolf species? I say, Are the imperfect circles we see in the materiel world of the circle species? The answer is yes and no. They are circles only to the extant that they correspond to the Ideal circle. In the same way coyotes and dogs are wolfs to the extant that they correspond to the ideal wolf you say, That is incorrect. The standard definition of species allows for interspecific hybridization. I say, The standard definition is subject to any number of ad hoc qualifications and aditions yet it still is subject to endless controversy among biologists. Isn't time we tried something new? peacefifthmonarchyman_{February 14, 2015
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fifthmonarchyman: So populations vary among and between themselves. More specifically, what biologists then and what biologists now call species have fuzzy boundaries. fifthmonarchyman: the species wolf Are dogs of the wolf species? Are coyotes of the wolf species? fifthmonarchyman: You can’t classify an organism into species until you define what a species is. We're asking how *you* are using the term. fifthmonarchyman: Using your definition I suppose a particular wolf would be a member of the population corresponding to those individual organisms that it can theoretically mate with and produce viable offspring That is incorrect. The standard definition of species allows for interspecific hybridization.Zachriel_{February 14, 2015
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Zac said, What Darwin did, and has been confirmed many times over, is that the species that were delineated by biologists had boundaries various in degree. I say So populations vary among and between themselves. Big surprise. The same can be said for the imperfect squares in the materiel universe. However in the world outside the cave there are no fuzzy boundaries in the species of square. The problem arises when you attempt to define what a square is by averaging the features of phyiscal squares instead of looking to the immaterial form you say, What species are wolves? I say. Short answer: the species wolf Long answer: You can't classify an organism into species until you define what a species is. Using your definition I suppose a particular wolf would be a member of the population corresponding to those individual organisms that it can theoretically mate with and produce viable offspring using the older definition a particular wolf would be a member of the species that exhibits the universal of wolf-ness but only to the extent in which it shares in that universal Form. peacefifthmonarchyman_{February 14, 2015
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No one argues for the fixity of species. YEC's baraminology allows for variation/ speciation. Linnaean taxonomy doesn't require the fixity of species. Ya see the originally created kinds would be species and baraminology says tat today's diversity evolved from that.Joe_{February 14, 2015
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fifthmonarchyman: Darwin used a classification system based on one definition of species to provide the boundaries for “species” according to another unrelated definition and found that it did not work What Darwin did, and has been confirmed many times over, is that the species that were delineated by biologists had boundaries various in degree. You might want to look at the actual data, something Darwin did, and what biologists do. What species are wolves?Zachriel_{February 14, 2015
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Zac said, That’s the classification used by Darwin and his contemporaries, and still largely in use today. I say, once again...second time...... Darwin used a classification system based on one definition of species to provide the boundaries for "species" according to another unrelated definition and found that it did not work, It still does not work after 150 years. Big surprise In other news it has been discovered that if we define marriage as a partnership between any group of people regardless of gender then suddenly the old boundaries of one male and one female no longer work "well duh" peacefifthmonarchyman_{February 14, 2015
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fifthmonarchyman: Platonic forms- see Linnaean Classification. That's the classification used by Darwin and his contemporaries, and Linnaean binomial nomenclature is still in use today. Darwin showed that species are not fixed, and have boundaries which are various in degree. - edited for clarityZachriel_{February 14, 2015
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Joe said, Platonic forms- see Linnaean Classification. I say, exactly! Zac says Again, Darwin used the species divisions as defined by other biologists I say, Species Divisions are only meaningful if we have a clearly understanding of what species is. Darwin did not like the concept of species as Forms so he used his own definition. He then attempted to shoehorn the divisions relevant to the older definition into his new "species are populations" frame work. he found that it did not work To which I respond "well duh" 150 years and we still haven't been able to accomplish fitting a round peg into that square hole check it out http://en.wikipedia.org/wiki/Species_problem Isn't it time we tried another way peacefifthmonarchyman_{February 14, 2015
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Platonic forms- see Linnaean Classification. Linnaeus was searching for the originally created kinds when he devised his systema naturae. And again thank you for finally understanding that gradual evolution doesn't predict an objective nested hierarchy. It feels good to see that you have finally come around.Joe_{February 14, 2015
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fifthmonarchyman: Since Darwin was mistaken as to which “populations” actually constitute his redefined “species” his conclusions as to the boundaries of said “species” are not the last word. Again, Darwin used the species divisions as defined by other biologists. fifthmonarchyman: “Platonic Form” is not an ambiguous concept it has been well defined for over 2 thousand years. Just because a concept is immaterial does not mean it is ambiguous. You haven't defined the platonic forms you are talking about, unless you are sorting animals into "circles and n-gons". Please tell us what forms they are, how many forms are involved, and how to sort biological organisms into these categories you have defined.Zachriel_{February 14, 2015
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It is entertaining watching Zachriel prove the case against unguided evolution predicting an objective nested hierarchy. Thank you Zachriel. It appears my work has finally gotten through to you.Joe_{February 14, 2015
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Zac said, As Darwin showed, the evidence indicates that species boundaries are “various in degree”. This is not what was expected by an ideal form with return to the mean. I say, Since Darwin was mistaken as to which "populations" actually constitute his redefined "species" his conclusions as to the boundaries of said "species" are not the last word. On the other hand think about the boundary between a circle and a n-gon it might appear fuzzy in the imperfect materiel world but it is perfectly distinct in the world outside the cave. You say. Defining species using a term that is ambiguous does not remove the ambiguity. I say, "Platonic Form" is not an ambiguous concept it has been well defined for over 2 thousand years. Just because a concept is immaterial does not mean it is ambiguous. That is unless you presume materialism peacefifthmonarchyman_{February 14, 2015
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fifthmonarchyman: I disagree and there is no way of demonstrating this with out presuming materialism As Darwin showed, the evidence indicates that species boundaries are "various in degree". This is not what was expected by an ideal form with return to the mean. fifthmonarchyman: If you define Species as Form or Kind there is not any ambiguity there is only various individuals that imperfectly correspond to the Ideal immaterial form. Defining species using a term that is ambiguous does not remove the ambiguity.Zachriel_{February 14, 2015
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Zac says. There is no ideal form. I say, I disagree and there is no way of demonstrating this with out presuming materialism you say, Boundaries between species are often ambiguous! I say, Of course they ambiguous are when you define species as population. If you define Species as Form or Kind there is not any ambiguity there is only various individuals that imperfectly correspond to the Ideal immaterial form. Just as squares in the phyiscal world imperfectly correspond to the Ideal square outside the cave. peacefifthmonarchyman_{February 14, 2015
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fifthmonarchyman: evidence please. Darwin, Origin of Species 1859, Sterility various in degree. fifthmonarchyman: this is what I have so far That's right. Many scientists had thought there was an ideal form. However, as Darwin pointed out, the distinct acts of creation were "unknown", so couldn't be used for species classification. When classifying organisms, scientists of the time generally used the phenetic species concept. fifthmonarchyman: I was much struck how entirely vague and arbitrary is the distinction between species and varieties That's a critical point of his argument. Boundaries between species are often ambiguous! There is no ideal form.Zachriel_{February 14, 2015
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Zac said, Darwin didn’t change how species were defined, but showed gradation between species as they were defined by biologists. I say, evidence please. this is what I have so far. quote: No one definition has satisfied all naturalists; yet every naturalist knows vaguely what he means when he speaks of a species. Generally the term includes the unknown element of a distinct act of creation. and it is a hopeless endeavour to decide this point on sound grounds, until some definition of the term "species" is generally accepted; and the definition must not include an element that cannot possibly be ascertained, such as an act of creation and ... I was much struck how entirely vague and arbitrary is the distinction between species and varieties Charles Darwin end quote: apparently Darwin did not feel there was a standard biological definition you say, In any case, Darwin didn’t redefine species. Rather, using the standard definition of species, he showed inconsistencies in how people thought about species, such as that they were fixed, or that they tended towards an ideal type. I say, again evidence please. From what Ive been able to discover he simply changed the definition of species from Kind/Form to population. Thus making his explanation the equivalent of. "variations in and among populations are caused by random variations that are filtered by nature" to this I say "well duh" peacefifthmonarchyman_{February 14, 2015
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fifthmonarcnhyman: According to this approach species are fixed ‘types’ and variability around this type is rather meaningless because there is no gradation between types, so evolution cannot occur; a cat is of the cat type, all cats are fundamentally the same and remain so through time. According to this approach species are fixed ‘types’ and variability around this type is rather meaningless because there is no gradation between types, so evolution cannot occur; a cat is of the cat type, all cats are fundamentally the same and remain so through time. Darwin didn't change how species were defined, but showed gradation between species as they were defined by biologists. fifthmonarcnhyman: He stressed the uniqueness of the individual, no two are the same. Which is largely true. fifthmonarcnhyman: These unique individuals form populations which can be considered in statistical terms; there is an average cat size, but all cats are different sizes and that average value is just a statistic. Again, true. fifthmonarcnhyman (quoting): Think of a cloud—just one cloud, and around it a clear blue sky That doesn't mean the grouping is completely arbitrary, just that there are ambiguous elements near the edges. The example you provided didn't have any ambiguous elements. In any case, Darwin didn't redefine species. Rather, using the standard definition of species, he showed inconsistencies in how people thought about species, such as that they were fixed, or that they tended towards an ideal type.Zachriel_{February 14, 2015
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In 1967 100 identical finches were released on a group of atolls in the Pacific. These atolls did not have any finches. 17 years later it was observed that the finches had diversified in both behavior and beak morphology, including accompanying musculature- to fit their respective new niches. What Darwin speculated taking millions due to the nature of the mechanism posited, actually takes over a decade due to the real mechanism involved, ie built-in responses to environmental cues.Joe_{February 13, 2015
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Zac said, Huh? Why would the grouping be arbitrary? I say, from here: http://plato.stanford.edu/entries/problem-of-many/ quote: Think of a cloud—just one cloud, and around it a clear blue sky. Seen from the ground, the cloud may seem to have a sharp boundary. Not so. The cloud is a swarm of water droplets. At the outskirts of the cloud, the density of the droplets falls off. Eventually they are so few and far between that we may hesitate to say that the outlying droplets are still part of the cloud at all; perhaps we might better say only that they are near the cloud. But the transition is gradual. Many surfaces are equally good candidates to be the boundary of the cloud. Therefore many aggregates of droplets, some more inclusive and some less inclusive (and some inclusive in different ways than others), are equally good candidates to be the cloud. Since they have equal claim, how can we say that the cloud is one of these aggregates rather than another? But if all of them count as clouds, then we have many clouds rather than one. And if none of them count, each one being ruled out because of the competition from the others, then we have no cloud. How is it, then, that we have just one cloud? And yet we do. (Lewis 1993: 164) End Quote:fifthmonarchyman_{February 13, 2015
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from here http://darwin200.christs.cam.ac.uk/pages/index.php?page_id=e8 quote: Prior to Darwin the dominant view of thinking about the natural world was typological thinking. According to this approach species are fixed ‘types’ and variability around this type is rather meaningless because there is no gradation between types, so evolution cannot occur; a cat is of the cat type, all cats are fundamentally the same and remain so through time. Darwin introduced a new way of thinking based on individuals, so called population thinking. He stressed the uniqueness of the individual, no two are the same. These unique individuals form populations which can be considered in statistical terms; there is an average cat size, but all cats are different sizes and that average value is just a statistic. Darwin’s new way of thinking about nature puts the emphasis on individual variation so opens the door for thinking about evolution. end quote: hope that helpsfifthmonarchyman_{February 13, 2015
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fifthmonarchyman: So? That only serves to prove my point? What point is that? That species grade into one another? That contradicts the notion of fixity of species, or that species revert to an ideal mean. fifthmonarchyman: Populations are not species. A species is a population. fifthmonarchyman: Species are groupings of things determined by their characteristics. At least that was the understanding of the word before Darwin. Yes, that's the definition that Darwin used, populations that have a high level of genetic similarity. There are several related definitions, and we know species tend to maintain their distinctive characteristics because of limited gene flow with other populations. fifthmonarchyman: What needs to be explained is why the shapes can be objectively grouped like that. It's called inheritance. Turns out that birds and bees reproduce and make more birds and bees. fifthmonarchyman: If I am given a bucket of birds for example I will be able to group them objectively into “species” according to their various physical characteristics. for example a Duck group and a Finch group. Duck and finch are family level designations. fifthmonarchyman: What you would expect to see on the other hand is that any grouping I make would be subjective and arbitrary as the individuals within each of the groups would vary as much as the differences in the groups as a whole. Huh? Why would the grouping be arbitrary? fifthmonarchyman: What was redefined was the term “species”. It went from being a term to describe the objective groupings that can be made in polygons or birds to a subjective fuzzy edged population with a relative reproductive isolation. You can still use the phenetic species concept, as Darwin did. He pointed out that two phenetically defined species may overlap. fifthmonarchyman: Once the term “species” was redefined Darwin proceeded to explain variation in and between populations by appealing to…….. wait for it ……random variation filtered by survival of the fittest. Darwin didn't define the term species. He used the traditional definition, then showed why in many instances species grade, and that it is reproductive isolation that maintains the phenetic distinctions that make for species.Zachriel_{February 13, 2015
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Zac said, Reproductive isolation is not a binary condition, but a range. I say, So? That only serves to prove my point. you say, The “issue” was variation within and between populations, that is, the delineation of species. I say, apparently you don't understand Populations are not species. Species are groupings of things determined by their characteristics. At least that was the understanding of the word before Darwin. Imagine I have a bucket of different polygons they can be grouped into different "species" according to the number of sides each contains. What needs to be explained is why the shapes can be objectively grouped like that. Not what it is that makes the individual shapes different from each other. To explain variation within and between a group of polygons by appealing to "random variation" filtered by "natural selection" is simply vacuous. Of course there is variation. That was never in doubt. The exercise can be done with a group of organisms as well. If I am given a bucket of birds for example I will be able to group them objectively into "species" according to their various physical characteristics. for example a Duck group and a Finch group. What you would expect to see on the other hand is that any grouping I make would be subjective and arbitrary as the individuals within each of the groups would vary as much as the differences in the groups as a whole. That is not the case and that is what needs to be explained. quote: A practical botanist will distinguish at the first glance the plant of the different quarters of the globe and yet will be at a loss to tell by what marks he detects them. :end quote Carolus Linnaeus you said Have no idea why you think pointing out that reproductive isolation varies in degree is a ‘redefinition’ of anything. I say, What was redefined was the term "species". It went from being a term to describe the objective groupings that can be made in polygons or birds to a subjective fuzzy edged population with a relative reproductive isolation. Once the term "species" was redefined Darwin proceeded to explain variation in and between populations by appealing to........ wait for it ......random variation filtered by survival of the fittest. All that can be said in response to that is...... well duh peacefifthmonarchyman_{February 13, 2015
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fifthmonarchyman: What? I don’t understand what you mean. Who is “they” and what is “grade”? Reproductive isolation is not a binary condition, but a range. fifthmonarchyman: For what? To explain the origin of species? He did not do that. The "issue" was variation within and between populations, that is, the delineation of species. For instance, Darwin was not an expert ornithologist, so when it came time to classify the various birds he found in the Galápagos, he relied upon John Gould, the noted English ornithologist; hence the classification was not determined by Darwin or colored by his theory. fifthmonarchyman: Then he acted is if his trivial explanation was actually actually an explanation of the origin of species by simply redefining terms. Have no idea why you think pointing out that reproductive isolation varies in degree is a 'redefinition' of anything. Rather, it's only one piece of observational evidence in his overall argument.Zachriel_{February 13, 2015
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Zac said, But they do grade, so we can dispense with that. I say, What? I don't understand what you mean. Who is "they" and what is "grade"? You say, Darwin generally relied upon the findings of other scientists. I say, For what? To explain the origin of species? He did not do that. What he did was attempt to explain variation in populations existing in relative reproductive isolation. As if that phenomena even needed any explanation in the first place. Then he acted is if his trivial explanation was actually actually an explanation of the origin of species by simply redefining terms. peacefifthmonarchyman_{February 13, 2015
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fifthmonarchyman: first of all you are mistaking me for BA77 again. We apologize for our clumsiness. fifthmonarchyman: I think it’s high time that we abandon the old Darwinian canard that “Species” is defined as a population in relative reproductive isolation. Darwin never defined species as complete reproductive isolation. He made a great point in "Origin of Species" to point out that isolation is by degree, an important component of his theory. fifthmonarchyman: If we define species as Form or Kind the irrationality of one fuzzy edged species bleeding into other species becomes obvious. But they do grade, so we can dispense with that. fifthmonarchyman: Darwin dodged the issue all together by redefining terms. No. Darwin generally relied upon the findings of other scientists.Zachriel_{February 13, 2015
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