“Species”

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On the thread entitled “Species Kinds”, commenter phoodoo asks:

What’s the definition of a species?

A simple question but hard to answer. Talking of populations of interbreeding individuals immediately creates problems when looking at asexual organisms, especially the prokaryotes: bacteria and archaea. How to delineate a species temporally is also problematic. Allan Miller links to an excellent basic resource on defining a species and the Wikipedia entry does not shy away from the difficulties.

In case phoodoo thought his question was being ignored, I thought I’d open this thread to allow discussion without derailing the thread on “kinds”.

1,428 thoughts on ““Species””

  1. fifthmonarchyman:
    But I was looking for examples from higher animals.

    You didn’t specify, but why aren’t plants allowed?

    I would say mine,

    Yes, I suppose you would. Hypocrisy seems to be a defining feature.

  2. Kantian Naturalist: 1. To say of something that it is conventional is not to say that it is not real; it is to indicate what kind of reality something has. Buddhist metaphysics distinguishes between ‘conventional reality’ and ‘absolute reality’. A distinction like that seems quite helpful.

    Helpful even when for Buddhists the absolute reality consists of just one thing and everything else is conventional? In Buddhist terms, to say that something is conventional is exactly to say that it’s (ultimately) unreal.

    Species is a term that evolutionists screwed up big time. It used to have some meaning or content until Darwin came and equated it with variety, resulting in obvious nonsense. There’s a major early Darwinian apologist I have been reading, Alfred Russel Wallace. He begins the first chapter of his Darwinism: An Exposition of the Theory of Natural Selection by noting that it’s important in the debate to have a clear understanding of the term “species”, then he cites some pre-Darwinian definitions, proceeds to the exposition of natural selection, and apparently unbeknownst to himself loses quickly track of any notion of species. The pre-Darwinian definition is cited (and disputed), but nothing better or clearer is offered in its place – in fact he offers nothing in its place at all and he doesn’t even notice, even though he begins by stressing the importance of having a clear understanding of it. Very enlightening reading. Warmly recommended.

  3. fifthmonarchyman: but that is exactly what you did and now you are trying to act as if you did not

    Indeed. It makes absolutely no sense if he’s not making an argument by analogy.

    I think being outed as a scientologist threw him off his game.

  4. Erik: Helpful even when for Buddhists the absolute reality consists of just one thing and everything else is conventional? In Buddhist terms, to say that something is conventional is exactly to say that it’s (ultimately) unreal.

    The idea that absolute reality consists of just one thing is an idea that I associate with the Upanishads. It’s not something that I’ve encountered in any of the Madhyamaka Buddhist texts that I’ve been reading lately. Perhaps I’m reading the wrong ones.

    Species is a term that evolutionists screwed up big time. It used to have some meaning or content until Darwin came and equated it with variety, resulting in obvious nonsense. There’s a major early Darwinian apologist I have been reading, Alfred Russel Wallace. He begins the first chapter of his Darwinism: An Exposition of the Theory of Natural Selection by noting that it’s important in the debate to have a clear understanding of the term “species”, then he cites some pre-Darwinian definitions, proceeds to the exposition of natural selection, and apparently unbeknownst to himself loses quickly track of any notion of species. The pre-Darwinian definition is cited (and disputed), but nothing better or clearer is offered in its place – in fact he offers nothing in its place at all and he doesn’t even notice, even though he begins by stressing the importance of having a clear understanding of it.

    The overall pattern of Darwin’s thought can be made tolerably clear by thinking about it in terms of what Peirce called “abductive inference”.

    Peirce characterizes abduction as follows:

    1. A observed fact, P, is surprising.
    2. But if Q were the case, then P would follow as a matter of course.

    Darwin’s version of this argument would be.

    1. There are many observed facts about the past and present of life on this planet.
    2. But if the species/variety distinction were a nominal distinction and not a real distinction, then many of these facts would follow as a matter of course.

    It shouldn’t be surprising that natural historians like Darwin and Wallace are not too helpful in explicating the concepts that they are using. (Also: Wallace was not an “Darwinian apologist”, as Huxley arguably was; Wallace discovered natural selection independently and was friendly with Darwin, though disagreed sharply with Darwin in several important respects.) It’s fairly routine in the history of science that clarification of basic concepts comes after the conceptual innovations that characterize a new research program. The same happened in general relativity and quantum mechanics.

    But for those interested in philosophical clarification of the underlying assumptions of evolutionary theory, I’d recommend works by Ernst Mayer, Eliot Sober, Michael Ghiselin, John Dupré, and Peter Godfrey-Smith.

  5. Kantian Naturalist: The idea that absolute reality consists of just one thing is an idea that I associate with the Upanishads. It’s not something that I’ve encountered in any of the Madhyamaka Buddhist texts that I’ve been reading lately. Perhaps I’m reading the wrong ones.

    That thing is Sunyata, from what I have heard. You could of course argue that it’s not a thing, and you would be right, but it still has a name.

    Kantian Naturalist: Also: Wallace was not an “Darwinian apologist”, as Huxley arguably was; Wallace discovered natural selection independently and was friendly with Darwin, though disagreed sharply with Darwin in several important respects.)

    Just observe the title of the book I mentioned. Yes, Wallace is an independent discoverer of natural selection, but he is also the apologist for it and he didn’t have any qualms calling the new trend in biology Darwinism, deliberately giving more credit to Darwin.

  7. newton: How does God reveal that there are true boundaries?

    one good way is by logic

    If there are species then there are true boundaries by definition.
    or
    If there are false boundaries then there are true boundaries

    peace

  8. Corneel: You didn’t say. What’s wrong with plants? What’s wrong with “lower” animals (whatever those are)?

    Absolutely nothing wrong with plants or lower animals. never once said there was

    We’ve known there was a lot of lateral gene transfer in those species for a very long time. The article I linked was about how we are discovering that this sort of thing is happening all the time in mammals.

    John’s claim as I understand it is that generally to be a considered a hybrid the ratio of genes needs to be 50/50.

    If that is generally the case there should be lots of examples of mammals with that ratio.

    This side discussion arose because I inquired what % introgression is necessary to deem an animal a hybrid

    peace

  9. Allan Miller: It is not necessary for genes to provide an advantage to become fixed.

    Of course you are correct. My point was that for every instance of introgression there are probably many interbreedings that leave no lasting trace in the genome

    peace

  10. John Harshman: You didn’t specify, but why aren’t plants allowed?

    See my comment to Corneel,

    It’s not that plants are not allowed just that copious amounts of lateral gene transfer in plants is already common knowledge. And therefore of little interest to the topic at hand

    peace

  11. Neil Rickert: Only if there is a human convention that specifies that it should be high water mark.

    But there is a true high water mark. if you stood at the end of time looking back you would certainly see a place that marks the highest place that water could ever go.

    And if you knew comprehensively everything about each and every moment you would know the true high water mark at any given moment in time

    peace

  12. Kantian Naturalist: FMM would hardly be a good example of a Christian if he weren’t condescending and passive-aggressive.

    What seems like condescension is really just my frustration at the lack of deep thought I often experience here. I mean come on, I know you all are smart cookies this shouldn’t be that hard.

    You can’t get real condescension from a fellow who spells as badly as I do. 😉

    I’m not really sure how I can be passive-aggressive and overly confrontational at the same time. 😉

    peace

  13. fifthmonarchyman: But there is a true high water mark.

    But why is that the boundary for Manhattan Island? Why isn’t it the average between high water mark and low water mark? Why isn’t the center line of the East River part of the boundary?

    We need human conventions to settle such questions, particularly if they are ever to be part of a court proceeding.

  14. Kantian Naturalist: Species can be perfectly real — “absolutely real”, if you like — even though our interests in biological explanation play a role in determining the exact spatial and temporal boundaries of a species.

    it’s just that interest in “biological explanation” that I think is misplaced when it comes to species.

    peace

  15. Neil Rickert: But why is that the boundary for Manhattan Island?

    I could choose a point 100 miles away in the ocean if I like. It’s a free country.

    On the other hand some of us would like to know what the true boundary is if we could. I’m not saying that it’s the high water mark but there is a true boundary.

    Neil Rickert: We need human conventions to settle such questions, particularly if they are ever to be part of a court proceeding.

    I’m not sure we do.

    Instead of trying to discover what people consider the boundary to be why not try and discover what the actual boundary is and then educate the folks?

    peace

  17. fifth,

    Nope, sorry but you are the one who is incorrect here. Neil said species were human convention not species boundries

    This isn’t difficult, fifth, though it will no doubt continue to baffle you.

    What lies inside the species boundaries is the species. What lies outside the species boundaries isn’t the species. If the boundaries are set by human convention, then what constitutes the species is itself a matter of human convention.

    What lies inside the city limits is the city. What lies outside the city limits isn’t the city. If the limits are set by human convention, then what constitutes the city is itself a matter of human convention.

    Cities and species are real, even if they and their boundaries are a matter of human convention. Your statement is incorrect:

    I think “conventional” implies not real so I would not use that terminology either.

  18. Erik: Species is a term that evolutionists screwed up big time. It used to have some meaning or content until Darwin came and equated it with variety, resulting in obvious nonsense.

    My thoughts exactly.

    Destroying language in this way would not be such a big deal except it is causing real harm to our conservation efforts.

    peace

  19. fifth,

    What seems like condescension is really just my frustration at the lack of deep thought I often experience here.

    Which is itself a condescending, and obviously false, statement.

    The fact that we disagree with you is an indication of our comparative intelligence, not of a “lack of deep thought.” We simply aren’t stupid enough to emulate your “deep” mistakes.

    Your arguments fail again and again. When are you going to notice the pattern?

  20. keiths: What lies inside the species boundaries is the species. What lies outside the species boundaries isn’t the species.

    Not even remotely true.
    a species is not bounded set of things with a ring around it denoting it’s edge
    a species is a group of instantiations of a quintessential pattern.

    peace

  21. keiths: Cities and species are real, even if they and their boundaries are a matter of human convention.

    If their boundaries are a matter of human convention, then their boundaries are a matter of human convention. Brilliant. Why didn’t fifth think of that?

  23. fifthmonarchyman: On the other hand some of us would like to know what the true boundary is if we could. I’m not saying that it’s the high water mark but there is a true boundary.

    Maybe there’s a true catholic boundary, a true presbyterian boundary, a true baptist boundary — and maybe they are not all the same.

  24. keiths: Your arguments fail again and again. When are you going to notice the pattern?

    This from the person who claimed: “my point is not to analogize species with cities.”

    LoL

  25. keiths: The fact that we disagree with you is an indication of our comparative intelligenc

    It’s not the disagreement that I’m talking about it’s the seeming inability to understand what is being discussed.

    like when I’m asked to show where in the Bible God revealed the definition of species.

    Or when someone thinks my logic would imply that New York city is not real

    peace

  26. Neil Rickert: Maybe there’s a true catholic boundary, a true presbyterian boundary, a true baptist boundary — and maybe they are not all the same.

    If they are not all the same then they are not all the true boundary. The true baptist boundary may or may not correspond to the true boundary.

    You are entitled to you own opinion but not your own truth.

    Peace

  27. Neil Rickert,

    Only if there is a human convention that specifies that it should be high water mark.

    Indeed! It’s mostly just humans that are bothered anyway!

  30. Allan Miller: You know of anything non-human that frets about where exactly to draw the boundaries of Manhattan Island?

    quote:

    And he made from one man every nation of mankind to live on all the face of the earth, having determined allotted periods and the boundaries of their dwelling place, that they should seek God, and perhaps feel their way toward him and find him.

    Acts 17:26-27
    end quote:
    😉

    peace

  31. keiths:

    What lies inside the species boundaries is the species. What lies outside the species boundaries isn’t the species.

    fifth:

    Not even remotely true.

    fifth, earlier:

    I have no problem with the idea that the boundaries we place on species being simply human convention.

    As Alan has pointed out I think the true boundaries are known to God

    I enjoy watching fifth trip over himself. It brings glory to Jesus.

  32. If their boundaries are a matter of human convention, then their boundaries are a matter of human convention. Brilliant. Why didn’t fifth think of that?

    Don’t be so dim, Mung. That isn’t the argument. Read my comment again.

  33. keiths: I enjoy watching fifth trip over himself.

    Here comes the frustration again. Do you really not understand something so simple as this???

    not to sound conceding but……….

    Of course species have boundaries but they are not defined by boundaries.

    Just like cities.

    come on keiths, think

    peace

  34. Mung:

    Indeed. It makes absolutely no sense if he’s not making an argument by analogy.

    Of course it does, and you can see that simply by looking at the original exchange:

    fifth:

    I think “conventional” implies not real so I would not use that terminology either.

    If species are not real then Darwin was wasting his time trying to explain their origin.

    keiths:

    By Fifth Logic ™, New York City is not real.

    Time to trade in your logic, Fifth.

    That is an argument by counterexample, not an argument by analogy. New York City is a counterexample to fifth’s statement, and it stands on its own.

  35. let me try and help you.

    Suppose you wanted to visualize the species “circle” would you say it is

    A) What lies inside a set of all circles.
    B) All shapes that instantiate the ideal circle

    Hint (A) is a nothing but a silly tautology.

    peace.

  36. keiths: New York City is a counterexample to fifth’s statement, and it stands on its own.

    FMM: “Human convention” implies “not real”
    Keith’s: by that logic New York city is not real
    FMM: What? Are you really saying that New York City is “human convention”
    Keith’s : No I’m saying New York city has boundaries just like species do
    FMM: You have got to be kidding me.
    Keith’s: It’s not an analogy it’s a counterexample
    FMM: LOL

    you can’t make this stuff up folks
    peace

  38. fifth:

    you can’t make this stuff up folks

    You just did.

    You can’t defeat my actual arguments, so you just made one up. That’s pitiful, fifth.

  39. fifthmonarchyman:
    let me try and help you.

    Suppose you wanted to visualize the species “circle” would you say it is

    A) What lies inside a set of all circles.
    B) All shapes that instantiate the ideal circle

    Hint (A) is a nothing but a silly tautology.

    Then again, organisms aren’t circles, and organisms don’t have Platonic ideals. Yet another bad analogy. What organisms have is genetics and history. Members of a species are similar because they share recent genetic history, and because there are mechanisms separating their recent genetic history from the genetic histories of other species. Species change, too. They even generate new species. How does that fit into your essentialism?

  40. keiths: You can’t defeat my actual arguments, so you just made one up.

    If those aren’t your actual arguments,
    You have done an amazing job of disguising your actual arguments.

    😉

    peace

  41. John Harshman: Then again, organisms aren’t circles, and organisms don’t have Platonic ideals.

    Says who exactly?

    John Harshman: What organisms have is genetics and history.

    Yes and the genetics and history we think we know don’t quite match what we see when we categorize them.

    John Harshman: Members of a species are similar because they share recent genetic history

    and how do we know they share a recent genetic history? Because they are similar of course 😉

    John Harshman: Species change, too.

    How do you know?

    John Harshman: They even generate new species.

    species aren’t agents or forces they don’t “generate” anything

    John Harshman: How does that fit into your essentialism?

    This is what Eric was talking about,

    You completely change the meaning of species until it is nonsense then construct a narrative that more or less fits your new nonsensical definition.

    And then ask me how a particular philosophy fits into your narrative.

    That is getting the cart before the horse, I don’t grant your definition it’s simply untenable and causes harm to our conversation efforts.

    I think what you should be doing is asking how your definition fits the facts we are discussing.

    peace

  42. fifth,

    not to sound conceding but……….

    Of course species have boundaries…

    So why did you respond with this…

    Not even remotely true.

    …when I wrote this?

    What lies inside the species boundaries is the species. What lies outside the species boundaries isn’t the species.

    Does it bring glory to Jesus when you, a Christian, deny something so blindingly obvious?

    World’s Worst Apologist.

  43. dazz: Is New York an instantiation of an ideal New York? How useless is that?

    nope, You are making the mistake everyone else did when we read Keith’s comments

    Despite what it sounds like Keith’s is not actually saying that New York city is like a species.

    He is saying that it has boundaries like a species and therefore by my logic and counterexample it is not real.

    right Keith’s

    😉

    peace

  44. keiths: So why did you respond with this…

    Not even remotely true.

    Because it is not even remotely true that what lies in the boundaries of a species is a species. I thought I made that clear.

    Of course species have boundaries but they are not defined by boundaries they are defined by the quintessential form they instantiate.

    If an entity outside of the boundaries instantiates the form it’s not excluded from the species….instead the boundaries move to accommodate it .

    Sort of like when New York City annexes a new subdivision while remaining New York. 😉

    peace

  45. fifthmonarchyman: He is saying that it has boundaries like a species

    I don’t think so. Species have no set boundaries, it doesn’t even make sense from an evolutionary standpoint.

  46. fifthmonarchyman: If an entity outside of the boundaries instantiates the form it’s not excluded from the species….instead the boundaries move to accommodate it .

    IOW, species have no boundaries, welcome to the evolutionist camp!

  47. dazz: welcome to the evolutionist camp!

    I never left it.
    Intelligent Design is not remotely anti-evolution it’s anti Darwinian evolution.

    peace

  48. dazz: I don’t think so. Species have no set boundaries, it doesn’t even make sense from an evolutionary standpoint.

    I know right? Species don’t have set boundaries but according to Keith’s

    quote:

    What lies inside the species boundaries is the species. What lies outside the species boundaries isn’t the species.

    end quote:

    Is that not a hoot? 😉

    peace

  50. Are finches with bigger beak different species than the finches with small beak?
    If yes, please provide evidence why…
    If not, please provide evidence why…

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