Species

A perennial topic. The organisms we see cluster around specific, distinct types. We can identify an individual as belonging to that type because it has the distinctive characteristics of that type. We know what the characteristics are because we see a lot of such individuals.

To the some Creationists, those types represent essential, immutable forms, perhaps with some post-Ark latitude, and a bit of variation around the ‘norm’. It is as if those forms were cast from a mould, with small manufacturing defects. The mould is eternal, unchanging.

To the Evolutionist, those types are simply the current form of a changing lineage. Lineages can branch and diverge leading to an increase in the total numbers, offset by extinction. The branching process is somewhat extended in time, so species are not only malleable but somewhat blurry around the inception of a bifurcation. Intraspecific variation does not become interspecific variation overnight.

The Creationist demands to know how one type can ‘become’ another – how one unchanging essence can become another unchanging essence. The Evolutionist answers that their conception of ‘species’ is awry – one type becomes another, or two, gradually, changing like minimalist music. The type ‘floats on the breath of the population’, as Dr Johnson said of the unwritten Erse language. The Creationist responds that this is begging the question – defining species in evolutionary terms is an attempt to prove evolution by definition.

Nonetheless, if you are talking of evolution, your species concept needs to take account of it. An essentialist conception is no use in an evolutionary framework. There is, in my opinion, no non-arbitrary means of distinguishing species from other taxonomic ranks while interbreeding (and hence gene flow) is possible. This is the limit of the Biological Species Concept – a biospecies is the set of all the individuals which can create viable fertile offspring with at least one other member of the set. This can frequently be far too broad – maples separated for 20 million years can interbreed, and fertile hybrids between morphologically distinct types, even those assigned to different genera, are common. It is also difficult practically to assess whether the sets are ‘really’ separate yet. At the extreme, a single introgression among billions of incompatible pairings would indicate incomplete speciation, to a BSC pedant.

Creationists claim an objective means (as they do in other arenas …) but take them out in the field and I suspect their hypothetical methodology would fail them. If we base it on ‘morphology’, just how does one rank characters objectively? A wing-bar, beak colour, gregarious, particular mating dance, blue eggs, prefers shrimps … how many characters, which ones are more important, and by how much?

I would take as an example the Spotted sandpiper and Common sandpiper. These are held to be an example of parapatric speciation – they occupy different but contacting ranges, and within those ranges, for reasons unknown, gene flow in a single ancestral species between the ranges gradually diminished. Potential causes include a temporary ‘firebreak’ where no individuals penetrated, dichotomous mate preference, or ecological specialisation. Now, again for reasons not entirely obvious, they do not penetrate each others’ ranges except in narrow contact zones. At these zones, hybrids frequently occur. So on the BSC, speciation is not complete (indeed, the Common also interbreeds with sandpipers of a different genus, so on the BSC they join in too). But they are clear morphological species. Are they Platonic? Were they both on the Ark?

477 thoughts on “Species

  1. Steve: Obviously, they mutate within the limit.
    It means scientists have not yet found a combination that requires the microbes to effect 3 mutations.

    There is no limit, Steve.

    And “requirement” is something humans assign after the fact.

  2. fifthmonarchyman,

    Thanks for the link to the quagga, FMM. Confessing I was previously unaware of this animal (had I been forced to guess in a Pub quiz, I’d have gone for something Australian!), I have to say that is one beautiful illustration of the fuzziness of species and the general difficulty of putting circles around anything in the real world.

  3. There was a time not so long ago when creationists asserted it was impossible for species to go extinct, because they were designed by god, and god wouldn’t allow it.

    This is what comes from believing the voices in your head.

  4. petrushka:
    There was a time not so long ago when creationists asserted it was impossible for species to go extinct, because they were designed by god, and god wouldn’t allow it.

    Hence, Skull Island.

  5. OMagain: Probably? Try harder. Actually use your proposed system and come up with a structured argument as to why you’d classify them as two rather then one. You know, science it up a bit?

    I would classify them as two because they have different morphology and habits and habitat. However before I could say definitively we would need to actually do the sort of measurements that biologists do.

    I’m not sure what you want here. I gave you specific examples now you ask for a structured argument. What’s next a peer reviewed paper to submitted to a journal?

    I still don’t think you understand. I am not trying to put biologists out of business. My approach would not allow us to magically classify species without actual data.

    What it would do is allow us to classify populations based on morphology and habits and habitat with out being hindered by questions about their ancestry.

    It would let us continue to assume that our intuitions are correct and species actually exist.

    The hard work of actually categorizing organisms into species groupings would still need to be done by biologists not folks with a little spare time on the internet

    peace

  6. Alan Fox: I have to say that is one beautiful illustration of the fuzziness of species and the general difficulty of putting circles around anything in the real world.

    It’s a good thing that centered sets are not circles.

    peace

  7. Alan Fox,

    What I find amazing is that you think that animals as different as the quagga and the zebra to be an example of fuzziness.

    You have certainly drunk the “populations are nothing but their collective genotypes” Kool-aid.

    peace

  8. fifthmonarchyman: What’s next a peer reviewed paper to submitted to a journal?

    Ideally, yes! Why not?

    fifthmonarchyman: I am not trying to put biologists out of business.

    I know. There will always be biologists.

    fifthmonarchyman: What it would do is allow us to classify populations based on morphology and habits and habitat with out being hindered by questions about their ancestry.

    Surely the more information the better?

    fifthmonarchyman: It would let us continue to assume that our intuitions are correct and species actually exist.

    Remind me why is that a good thing again?

    fifthmonarchyman: The hard work of actually categorizing organisms into species groupings would still need to be done by biologists not folks with a little spare time on the internet

    Give them a chance and explain how you determine what is the archetype and the organisms that are connected to it.

  9. fifthmonarchyman:
    Alan Fox,

    What I find amazing is that you think that animals as different as the quagga and the zebra to be an example of fuzziness.

    As different? It’s a beautiful example of the bifurcating tree of life. Fascinating.

    You have certainly drunk the “populations are nothing but their collective genotypes” Kool-aid.

    Not sure what you mean by this. What I think about species, populations, genes, sex and time would take more time to recount than I can spare currently.

  10. OMagain: Remind me why is that a good thing again?

    quote:

    “If there are certain principles, as I think there are, which the’ constitution of our nature leads us to believe, and which we are under a necessity to take for granted in the common concerns of life,’ without being able to give a reason for them; these are what we call the principles of common sense; and what is manifestly contrary to them, is what we call absurd.”

    end quote:

    THOMAS REID

  11. OMagain: Give them a chance and explain how you determine what is the archetype and the organisms that are connected to it.

    How do you determine what the archetypical circle is? You determine the archetype of any species the same way.

    How do you determine if a particular shape is connected to the archetypical circle?

    You use the same method for any species

    peace

  12. What’s an archetype? Are talking about Platonic forms? Trying to bend reality to our perceptions rather than observing, measuring, experimenting, then forming hypotheses to best fit the data.

  13. A little shared background knowledge would make these conversations easier

    Have you all read Michael Denton’s book “Nature’s Destiny”?

    peace

  14. Alan Fox: Trying to bend reality to our perceptions rather than observing

    What exactly is the difference between a perception and an observation??

    peace

  15. Alan Fox: Ah, apparently so. 🙂

    Do you recall the chapter on the principle of plenitude?

    Allow me to speculate a little bit.

    One way to think about archetypes might be to think of nature as 4 dimensional grid of available niches, an archetypal organism would fit ideally into every particular square on that grid.

    peace

  16. Alan Fox: Should have said “preconceptions”. Mea culpa.

    No problem.

    I would say the Forms are not preconceptions but “perceptions” of how the world actually is?

    peace

  17. fifthmonarchyman: One way to think about archetypes might be to think of nature as 4 dimensional grid of available niches, an archetypal organism would fit ideally into every particular square on that grid.

    In some ways I find it helpful to think of a species (a population of interbreeding organisms – this only works with organisms that reproduce sexually, of course) in four dimensions. You can imagine the world-lines of the genes, individuals and the population all interweaving through the environment that also changes over time.

    How does FMM’s archetype fit in and why does he need the concept?

  18. Apparently he needs the concept to deny evolution happened. Or at least that common descent happened.

  19. Alan Fox: How does FMM’s archetype fit in and why does he need the concept?

    Since you asked so nicely I will treat you to some heavy duty speculation.

    Like everything in creation I feel that the tapestry of life is best understood tri-perspectively.

    In this case the three perspectives are

    1) the perfect atemporal Form/4 dimensional grid
    2) the moving pulsing interweaving illusive physical presence represented by the genomes of the organisms themselves
    3) The probability distribution that connects the two and gives concrete exemplification.

    I think that my approach provides the needed context of the other two perspectives.

    I think the “problem of species” is the result of neglecting 1 and 3 and treating number 2 as all that there is.

    peace

  20. fifthmonarchyman: One way to think about archetypes might be to think of nature as 4 dimensional grid of available niches, an archetypal organism would fit ideally into every particular square on that grid

    The “niche space” sounds very much like standard Niche Theory, propounded by the famous ecologist G. Evelyn Hutchinson in the 1950s. It set off lots of work by theoretical ecologists who followed the lead of Hutchinson’s wonderful student Robert MacArthur. This included theoretical quantitative genetics models in the 1970s.

    One main evolutionary angle would be that niches that are far away from existing ones should tend to remain unoccupied. That would be expected on evolutionary grounds, but hard to explain on grounds of pure Platonic idealism (or whatever one calls that).

  21. petrushka: Apparently he needs the concept to deny evolution happened. Or at least that common descent happened.

    Thank you

    It’s statements like this that let me know that you don’t care at all about actual discussion. You don’t even care if you understand the views of those on the other side.

    You just want to get some digs in on the evil ignorant fundamentalist. Hope it was fun for you.

    peace

  22. Joe Felsenstein: One main evolutionary angle would be that niches that are far away from existing ones should tend to remain unoccupied. That would be expected on evolutionary grounds, but hard to explain on grounds of pure Platonic idealism (or whatever one calls that).

    There is a difference between generic niches and available niches. Just because God can imagine something does not mean that he has to actualize it.

    Just because a particular niche is far away in three dimensions right now is no reason to believe it will not be in reach later on that is the beauty of a four dimensional grid.

    peace

  23. fifthmonarchyman: You don’t even care if you understand the views of those on the other side.

    And you don’t care if you are ignorant of the entire history of a branch of science but you know better anyway!

  24. fifthmonarchyman: One way to think about archetypes might be to think of nature as 4 dimensional grid of available niches, an archetypal organism would fit ideally into every particular square on that grid.

    I asked you how you determine which specific organism is the archetypal organism. You have not even addressed that question.

    Name one.

  25. fifthmonarchyman: Since you asked so nicely I will treat you to some heavy duty speculation.

    Speculation?

    fifthmonarchyman: I think that my approach provides the needed context of the other two perspectives.

    Yet no mention of “speculation” here. Your “approach” works, according to you rather then it being speculation.

    If your approach works, demonstrate it working or admit it’s of no practical use to you or anyone else.

    If it does not work for you how can anyone else be expected to be interested? Demonstrate a worked example or admit it’s just idle speculation.

  26. fifthmonarchyman: It’s statements like this that let me know that you don’t care at all about actual discussion.

    Does evolution happen without gods intervention?
    Do you accept common descent?

    Simple questions with yes or no answers. You’ll lose points for bible quotes.

  27. fifthmonarchyman,

    Ever hear of revelation. It’s the only way we can have any idea about anything. If God chooses to reveal something to us we can know it if not we are forever in the dark

    God is revealing the secrets of his Creation through me. You simply choose to be blind to the evidence of his handiwork, and follow false revelation.

  28. fifthmonarchyman,

    I have made it clear that I believe that species are centered sets. Why do you continue to attack a bounded set straw man?

    I don’t see ‘centred set’ appearing anywhere other than in Christan apologetics, on a quick Google. Real organisms must be a bounded set. There are a finite number of them. If you don’t want people to think of a mathematical set when you use the term, don’t say ‘set’ at all. It’s not a strawman, it’s a necessarily entailment of trying to use ‘sets’ to delineate biology. If you’re talking front loading, you are talking real organisms exploring the ‘ideal’ space. The set of those is finite and hence bounded.

    A centered set approach would start with the archetype and then connect every organism that exemplifies that archetype regardless of how far it is away from the center.

    Well … yeah. So every organism that ever existed is in it. Or, you arbitrarily decide that a new organism is not in the same set as its parent(s). Take your pick.

    There are no dark circle boundaries in a centered set just an archetype and the organisms that are connected to it.

    If you decide you need a new set, that’s a ‘dark circle boundary’ right there.

    A descendant organism may or may not be a part of the same set as it’s parent depending only on whether they exemplify the same archetype.

    If an offspring in a sexual population does not represent the same archetype, who does it mate with?

  29. fifthmonarchyman,

    Now out of the ground the LORD God had formed every beast of the field and every bird of the heavens and brought them to the man to see what he would call them. And whatever the man called every living creature, that was it’s name

    Doesn’t sound like God gives a damn about the species problem. ‘”Call it what you like’, saith He”.

  30. fifthmonarchyman,

    What it would do is allow us to classify populations based on morphology and habits and habitat with out being hindered by questions about their ancestry.

    A new scheme for settling paternity suits and ethnic groupings: “What it would do is allow us to classify people based on morphology and habits and habitat without being hindered by questions about their ancestry. ”

    Why on earth would we ignore genetic relations in taxonomy? Here’s a whole bunch of additional data we are just going to ignore because – look! – a Wikipedia article on phenetics!

  31. fifthmonarchyman,

    You have certainly drunk the “populations are nothing but their collective genotypes” Kool-aid.

    So you missed my clarification of that statement?

  32. fifthmonarchyman,

    My approach would not allow us to magically classify species without actual data.

    We’d just hide the genetic data under the lumpy carpet somewhere – God forbid we should allow a foot in the door to common descent, despite this being an entailment of both ‘front-loading’ and post-Ark models, for them what subscribes to ’em.

    It would let us continue to assume that our intuitions are correct and species actually exist.

    The benefit being … ?

  33. fifthmonarchyman,

    1) the perfect atemporal Form/4 dimensional grid
    2) the moving pulsing interweaving illusive physical presence represented by the genomes of the organisms themselves
    3) The probability distribution that connects the two and gives concrete exemplification.

    You forgot harmonious quantum interfibrillation and deodactic alignment.

    Still don’t see how you determine whether those sandpipers are one or two ‘true’ species in God’s mind or anyone else’s. They appear to compete for a niche, since they apparently exclude each other, so ‘ideal ecology’ doesn’t work either. The availability of a niche is, of course, contingent on what is already in it, so it’s hardly something that can be idealised anyway.

    Time, I suspect, to stick a spork in it.

  34. Allan Miller: You forgot harmonious quantum interfibrillation and deodactic alignment.

    I hope you were sitting inside your cardboard pyramid when you wrote that, as otherwise your Chi may be misaligned.

  35. OMagain: I asked you how you determine which specific organism is the archetypal organism. You have not even addressed that question.

    Name one.

    the archetype is not a spesific physical organism but a form in the mind of God

    OMagain: Yet no mention of “speculation” here. Your “approach” works, according to you rather then it being speculation.

    the speculation is not about my definition of species but about how the three perspectives are related.

    OMagain: Does evolution happen without gods intervention?

    Nothing happens with out God’s causing it to happen.

    OMagain: Do you accept common descent?

    “accept” is a funny word so is “descent”

    Are Roundup Ready Soybeans directly descended from Glycine max or Agrobacterium tumefaciens?

    I would say the evidence seems to favor a common origin for life forms on earth. Discovering just how that happened is one reason why we do science.

    peace

  36. Allan Miller: You simply choose to be blind to the evidence of his handiwork, and follow false revelation.

    That is possible. There are tests we can administer to see if you have actually received revelation. Do you want to go that route?

    Allan Miller: Real organisms must be a bounded set.

    The other Allen thinks they are a fuzzy set you might want to take it up with him

    Allan Miller: So every organism that ever existed is in it. Or, you arbitrarily decide that a new organism is not in the same set as its parent(s). Take your pick.

    I don’t decide. An organism either exemplifies an archetype or it does not. Just like a geometric shape is either a circle or it is not. We might disagree about whether an object we encounter in nature is circular or not but we just can’t arbitrarily call any ole rock a circle.

    Allan Miller: If an offspring in a sexual population does not represent the same archetype, who does it mate with?

    Everything doesn’t have to be about sex. I’m amazed at the obsession with that subject. Different species can and do interbreed. Ever hear of ligers?

    Allan Miller: Doesn’t sound like God gives a damn about the species problem. ‘”Call it what you like’, saith He”.

    God is a Trinity he is deeply and intimately connected with humanity

    The Logos became flesh. Remember

    Allan Miller: A new scheme for settling paternity suits and ethnic groupings:

    Do you think the species problem and paternity suits are the same thing? Ancestry is very important to biology just not to species categorization.

    As far as ethnic groupings go America has a president who identifies as black but who’s mother was caucasian . A local head of the NAACP identifies as black despite having two caucasian parents. It seems like this ethnic grouping thing has a lot more to it than just parentage

    peace

  37. Allan Miller: Why on earth would we ignore genetic relations in taxonomy?

    Because genetic relationships are completely beside the point in taxonomy. When categorizing anything else we don’t care about genetic relationships. Why should we care about it when we categorize organisms?

    Allan Miller: God forbid we should allow a foot in the door to common descent, despite this being an entailment of both ‘front-loading’ and post-Ark models, for them what subscribes to ’em.

    What does common decent have to do with anything. This is not about common decent it is about species.

    peace

  38. fifthmonarchyman: the archetype is not a spesific physical organism but a form in the mind of God

    Yet your scheme depends on knowing what it is.

    fifthmonarchyman: the speculation is not about my definition of species but about how the three perspectives are related.

    And you’ve given no practical benefits so far.

    fifthmonarchyman: Nothing happens with out God’s causing it to happen.

    How predictable. How specific do you need me to be? But if god is doing everything deliberately, your god is a shit. Cancer, parasites, eye-worms. Your god is a shit.

    fifthmonarchyman: “accept” is a funny word so is “descent”

    Has god revealed to you that common descent is true?

    fifthmonarchyman: Are Roundup Ready Soybeans directly descended from Glycine max or Agrobacterium tumefaciens?

    Which of those is the archetypal version?

    And way to avoid answering the question.

    fifthmonarchyman: I would say the evidence seems to favor a common origin for life forms on earth. Discovering just how that happened is one reason why we do science.

    You don’t have the right to use “we” there. You don’t understand science, you don’t accept science and you reject science. You might not agree, but that is expected.

  39. fifthmonarchyman: I would say the evidence seems to favor a common origin for life forms on earth. Discovering just how that happened is one reason why we do science.

    What evidence? And why do you accept that evidence?

  40. fifthmonarchyman: What does common decent have to do with anything. This is not about common decent it is about species.

    Common descent does impinge on the notion of species, you know.

    Do you imagine that the first member of a new species is of a different species than its parent?

  41. fifthmonarchyman: As far as ethnic groupings go America has a president who identifies as black but who’s mother was caucasian . A local head of the NAACP identifies as black despite having two caucasian parents. It seems like this ethnic grouping thing has a lot more to it than just parentage

    A seems a bit fuzzy, what is the platonic version of black?

  42. fifthmonarchyman,

    There are tests we can administer to see if you have actually received revelation.

    Oh really … These tests are reliable?

    Still, it’s not whether I have received revelation, it’s whether you are, through the medium of me.

    Allan Miller: Real organisms must be a bounded set.

    The other Allen thinks they are a fuzzy set you might want to take it up with him

    The other ‘Allen’ thinks the same as me. Perhaps you have misunderstood. The entirety of real organisms is a bounded set. Any particular subdivision of this superset is also bounded. The fuzziness comes when deciding which discrete bin to put organism A in. But whichever set you decide to put it in, is a bounded set. Different criteria provide different finite subdivisions, but if you want individuals to only exist in one set, those sets must be bounded.

    I don’t even know what a ‘centred set’ is. Can you provide a definition that does not refer to a Christian site?

    I don’t decide. An organism either exemplifies an archetype or it does not. Just like a geometric shape is either a circle or it is not.

    A shape that is not a circle is an ‘archetype’ of some other shape. It lives in a set all by itself – the set of shapes that are shaped like ‘this’ (waves hands in air). The set of circles contains only circles. The set of squiggles of ‘this’ shape contain only squiggles of ‘this’ shape. That’s why this idea of archetypes more readily maps individuals than broader collections. There is an infinity of ellipse ‘archetypes’, from almost-a-circle to almost-a-straight-line.

    Allan Miller: If an offspring in a sexual population does not represent the same archetype, who does it mate with?

    Everything doesn’t have to be about sex. I’m amazed at the obsession with that subject. Different species can and do interbreed. Ever hear of ligers?

    In an obligate sexual population, reproduction has to be about sex! That includes most of the organisms that really interest us. It is hardly an ‘obsession’. Ligers can occur because there is more than one reproductively compatible individual. The first non-archetypal organism has no-one to mate with because there is no other reproductively compatible individual. So, are you suggesting reproductively compatible individuals simply pop up en bloc? Have you heard of the term ‘ad hoc‘?

    Allan Miller: Doesn’t sound like God gives a damn about the species problem. ‘”Call it what you like’, saith He”.

    God is a Trinity he is deeply and intimately connected with humanity

    In the Biblical passage quoted, he gives Man the option of choosing whatever species concept suits him. “God is a Trinity/God is fleshy, therefore he does care about the species problem” is not the most compelling argument you have come up with. Perhaps God is aware that Man has a limited understanding, therefore he needs categories – God is more subtle and can deal with continuums without getting flustered about where to place the razor. You seem to want to limit God by your intuition.

    Allan Miller: A new scheme for settling paternity suits and ethnic groupings:

    Do you think the species problem and paternity suits are the same thing? Ancestry is very important to biology just not to species categorization.

    “Ancestry is very important to biology”. Hmmm. Just not to species?

    As far as ethnic groupings go America has a president who identifies as black but who’s mother was caucasian . A local head of the NAACP identifies as black despite having two caucasian parents. It seems like this ethnic grouping thing has a lot more to it than just parentage

    Ethnic groups can mix, but there are diagnostic markers, particularly on nonrecombinant mitochondrial and Y DNA, that allow fine scale discernment of subsets of humanity. Much the same is done with many other organisms – there is shading from races and varieties, through subspecies and up.

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