Can Domestic Selection cause Macroevolution?

I was kidding. Most of the places I work don't even have electricity, let alone TV. I am now totally in love with that word. Did you just invent it or is it in common usage? I have a "cleptoparasite" living in my back yard - the glossy flowerpiercer (Diglossa lafresnayii) that bypasses the pollen and punches a hole in the bottom of the flower's nectary. Pretty bird, tho'.

I did not consider our relationship with corn to be either commensualistic or mutualistic, but only parasitic. Since that was the only relationship I was considering, it makes logical sense to say that the only symbiotic relatioship would be parasitic.It also seems that you do not want to call mankind parasites, though we potentially can be and are (never mind that most parasites are incredibly small, like fleas or mosquitos).If the ecologists have separated a parasitic relationship as falling under a symbiotic relatioship, so that it is now one on its own, then what you are saying is not contraditcory.The final option is that we both misunderstood each other's post. You were trying to point out that other relationship's are symbiotic, and I was saying that our relationship with corn is symbiotic only if it is parasitic, becasue I did not consider the other two as possible descriptions of our relationship with corn. Not to say that I didn't know about them, but that I thought the relationship did not fit under those further defined categories.

Scientists aren't aiming for anything. They are maintaining naturally-occurring mutations for various reasons. A few thousand mice is nothing, though, in the world of mass-production and highthroughput mouse genetics. The Jackson Lab, for example, has a few thousand different lines of mice actively breeding - I'm guessing at least a few thousand mice are born every day in their facility.Besides, many mutations are found because they produce abnormal phenotypes, which are particularly obvious in homogeneous inbred mouse strains. No detailed genetic testing needed. Not sure of the ratio of induced to natural. But, that doesn't really matter for the question that serves as the topic title. What does matter is that humans selectively bred natural variation within one population to produce two populations that are no longer interfertile. Thus, artificial selection can produce speciation.

Yes, drift could potentially result in speciation, which is why I said "generally" different selective pressures would be required. The accruement of intergroup variation is going to be stochastic and relatively much slower in the absence of selection. If both groups stay under strong normalizing selection, variation will be kept at a minimum (selection would maintain them as a single species).There is at least one example of a species with populations that have been isolated since Pangea split into continents (some sort of lettuce-like plant?), but remain one species - despite an enormous time of isolation (and drift). On the other hand, there are cases of explosive sympatric speciation of hundreds of fish species occurring in the past million years or so in the African rift lakes - I would argue under very strong selection, and largely without isolation events.I guess my overall point is that I don't see the point in trying to rank processes like isolation, selection, and drift when it comes to their contribution to speciation.

Really, a cerambycid? Sounds interesting, I'll have to look it up.Sounds like we have some things in common... I work with forest insect pests. And I'm a cyclist, too .

Cleptoparasitism is an accepted term within parasitology.For example, here is an article about one wasp that follows searching females of another species to steal their hosts. (edited to fix link)I'm betting Guatemala, for one, based on the moniker.This message has been edited by EZscience, 04-07-2006 02:01 PMThis message has been edited by EZscience, 04-07-2006 02:17 PM

In allopatric speciation it is unlikely that there would be direct selection for infertility. Therefore I would tend to the view that drift is generally the most important factor.In sympatric speciation selection would almost certainly be needed for speciation to occur, but that is generally regarded as far less common than allopatric speciation.!

You can see a picture of the insect here and read a recent article about this pest
hereI did a post-doc at U of F for 7 years - did the Cross Florida ride twice. Best time was 7 h, 23 min.My faculty position kind of killed my cycling 'career', but I hope to revive it. (Picture is from Terrible Two ride, Santa Rosa CA, 2001)

So they're pretty much looking for the karyotype, and then breeding a strain which has that karyotype. This karyotype predisposes to incompatibility; so essentially they are breeding for incompatibility. It might not be their expressed aim, but it is a trait caused specifically by the karyotype they are breeding for.And it goes to what i said at the end of my last post... artificial selection is causing speciation, by being directed to do so.I didn't mean to imply that DS can not cause speciation.

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"The good Christian should beware the mathematician and all those who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and to confine man in the bonds of hell." - St. Augustine

Of course this is a theoretical situation, so normalizing selection does not necessarily have to apply.Its one thing to know that speciation involves the factors, but why wouldn't one want to know how each factor contributes to a specific case of speciation, especially if there is a possibility of differential contribution. At the very least it allows for an increase in knowledge.

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"The good Christian should beware the mathematician and all those who make empty prophecies. The danger already exists that the mathematicians have made a covenant with the devil to darken the spirit and to confine man in the bonds of hell." - St. Augustine

Absolutely, sorry if I misread you. It had seemed to me that you were trying to rank them in a general sense that would apply to all speciation events; now I see you are referring to understanding specific instances - which I take no issue with.

It doesn't have to be direct, and I didn't mean to imply such. Selection for other phenotypes can indirectly, and readily, cause reproductive isolation. Doesn't follow for me from your previous statement.Selection that indirectly alters reproductive compatibility is still selection, not drift. Selective forces that differ between the two niches that the two isolated populations inhabit will cause divergent evolution between those populations.And, as in my comments to Cookie above, I think it is a mistake to make generalized comments about the processes involved during speciation.

Thanks for the article. I've downloaded it into my "neat to keep" files.Guatemala, nope. Formerly Nicaragua, now Ecuador (they still have quetzals, but they're pretty pitiful compared to the Nica or Guatemalan subspecies).

Right, and that's the source of your mistake. If you had not ignored, or forgotten, that there were at least 2 other symbiotic relationships, you would not have stated that the human-corn relationship could not be symbiotic if it were not parasitic. There's nothing logical at all about that conclusion; in fact, it's fallacious. It's the fallacy of denying the antecedent. It's simply not an accurate description of our relationship with corn. We protect corn, we rear it, we spread its seed in the course of our use of it as a crop. It benefits from our husbandry. The relationship is one of mutualism, not one of parasitism. According to the definitions of these words there's really no other conclusion. Then it would have been better for you to rebut my argument that it did fit under the category of mutualism, rather than blowing your stack about an imagined contradiction.At any rate, water under the bridge. Would you care to address my argument at this time?

it appeared to be a contradiction. Is it not illogical to say that a rectangle is not the same as a sqaure and then to include, as part of the defintion of a rectangle, a square?When I said that mutaulism could take the place of parastism in my origninal statement of "its only symbiotic if it's parasitic" I was not implying (or I did not think I was implying) that the two are the same (mutualism and parasitism), but that M would still fit into my statement for the purpose of discussion. That was why we said the same thing, for the most part. The only difference--how we classify the exact relationship.I still don't see how corn derives any benefit from our relationship. We grow it. We care for it. We control it genes. We use it. We plant it. But does it grow as a species? Does it evolve? I would say no. Everything we do for corn is soley for our benefit, or at least that's how I interpret the evidence.That first quote isn't a mistake. I did not forget or ignore the other relationships. So in order for the relationship to be symbiotic, it then has to be parasitic. You know how on a multiple-choice test, if you eliminate all possibilities except one, that last one then has to be it? I did the same thing. Nothing wrong with that.