>>Please understand, I am not arguing anything. I have my beliefs and you can have yours. We are here to think, and ponder these snakes.
>>

Frank, thanks for hanging in there with me. I don't want to argue either. I just meant discuss, etc. Hard to get the right word in that context. I agree about thinking and pondering on these snakes. I tend to have sort of a global view over time. I don't pretend to be an expert, just giving my opinion. I just like the debate and will never try to tell someone what to believe or think. But I do think there's education and science going on here.

>> First, I disagree on continous gene flow. If that were so, there would not be locality types, But hey, there are locality types. You mention corn snakes, they are a great example on this. Every county has its own morph of corn snake. While they are all corn snakes, they all have unique local qualities. Just look at them. If they outbred, this would not be so prevalent. This occurs with kingsnakes as well as many many kinds of snakes.
>>

Right. There are locality morphs. But this is a snapshot in time. When we put a snake in a collection it is dead to the species. There's no more gene flow from that snake. It will remain the same now and produce babies that are genetically like itself or what you breed it with.

Example: last year we talked about Brazos Island ratsnakes from se. TX quite a bit. Some people pondered calling it a new subspecies, but it is just a Great Plains ratsnake, or part of the "meahllmorum" ssps, if you recognize that. Yet, it is distinctive enough for folks like me to want a pair. That does not mean there's no gene flow in the wild. It shares 99.9% of the same genes as the rest of the species.

>> Let me ask, do you fellas just step out your door and collect, or just stop the car and collect? No sir, you go to a particular place, Why??????? why there and not anywhere? Does every acre of south texas have getulus????? I don't think so.
>>
>> I think the problem is understanding range maps, in the old days, they used site maps, that is, there was a dot for an individual snake. These dots were not space evenly over the range, but in clumps. Then someone decided to draw a line around the outside dots, and call that their range. But that is false, the dots are the range and not the areas inbetween. Now what that really says is, is their perferred habitat continious, again that answer is no, their perferred habitat is fragmented. Now because its fragmented, geneflow is also fragmented.
>>

Preferred habitat is good scientific info, but remember, over time the land is always changing. The group we go to today, like Brazos Island, for instance, may not be there a hundred or a thousand years from now. That's a temporary situation. Over time that group will be connected to the species and have gene flow. I'm not saying snakes don't have the morphological differences you're pointing out.

>> I would bring up behavior, but that would do no good here. But I will say, behaviorally snakes are territorial and inbreed by nature. One would have to ask why a snake combats some males and not others. In all the groups I have studied, there are many males and they never combat. Yet on a very rare occasion, you see two males combating and on even rarer occasions, you can find females combating. They combat, individuals that are not of their group. Even if this is absolutely correct, it still does not prevent occassional outbreedings or even mass outbreedings for particular events. Take the gulf coast, if the colonies of reptiles were all clean cut and set, after the flood, it certainly changes the whole dynamic. This is most likely how outbreeding(geneflow) occurs.
>>

I agree, snakes interact with other snakes in their local population. Gene flow happens over time. Sometimes populations don't have to be connected to have had gene flow recently.

Another example: There's a population of Great Plains ratsnakes in western CO and eastern Utah that is separate from the main population, and they look quite a bit different from the average G P rat. Recent studies have determined that genetically the pop. is identical to P. g. emoryi, however, and currently they are just seen as G P rats, "emoryi". They used to be seen as P. g. intermontana, my preferred designation because of their looks. My point is they are still G P rats in spite of the isolation, and not even different enough to make ssps a permanent designation.

>> Snake populations are never static, they are either expanding or contracting. In a very wide view, this happens over tens of thousands of years as well on a year by year basis.
>>
>> When a reptile is rapidly expanding its range, there is rapid geneflow, when they are contracting their range, there is no gene flow. This develops locality types.
>>
>> Now with time, and another expansion, they out breed again, then are isolated for thousands of years. This is a better picture of how it works. They do not have continious anything. Its all a matter of history.
>>

I understand. We have some problem with each other's wording. Gene flow doesn't have to happen very quickly. It's like water, eventually it'll seep into the cracks and all the places on the correct elevation. I agree with what you're saying, except I think of gene flow as continuous because all the snakes of a species have basically the same genes even though some things are changing over time and space. You're saying populations of the same species are isolated where there is no gene flow, which is a temporary thing.

There's also the fact that gene flow can be very slight between two sister groups, like corn snakes and G P rats, and maybe not even noticeable for a lot of folks. I believe two populations should be the same species no matter how small the gene flow, if the two populations share basically the same genes.

>> What I find odd is, why people think its one or the other, and not all of the above and more. Mostly whats misunderstood is time. Man has been on earth for less time then it takes a snake species to migrate. Again, just something to think about. FR

Thanks for the great strand and I agree with most of what you're saying. I think we're looking at gene flow differently, but we can work that out. Probably most folks don't think about it at all.

I would mention that there's certain areas that are very dynamic because of the meeting of different habitats and related subspecies, etc. One of those places is se. TX. I feel there's got to be some intergrading going on along the Gulf Coast. Could be fodder for another day, as I'm off to work now.

Later....TC

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