Posted by:
ratsnakehaven
at Tue Sep 20 13:11:03 2005 [ Email Message ] [ Show All Posts by ratsnakehaven ]
>>To me, an intergrade is the product of a breeding from two forms that are at least slightly divergent from each other (i.e. subspecies). >>
Joe, no problem with your defintions, but the idea of intergrade is confounding me. I agree that if two subspecies mate with each other the product would be an intergrade. But normally two subs don't get that close to each other because there's an intergrade zone bt. them, an area where a mixture of their genes creates a somewhat intermediate form.
Because I believe there's gene flow from both subs into the intermediate form and mixing of genes, I believe this to be an intergrade.
If you take two subs in captivity and cross them, then I would call this a "cross", not an intergrade because they wouldn't mix the same way in the wild. I know this idea causes concern and confusion for breeders. And then there's the people who breed and don't even know what it is that they're breeding. Yippee!!!
>>However, IF splendida and holbrookii are just natural variants of getula and can not be separated by distinctive traits, then those "intermediate forms are not true "intergrades". >> >>This premise is basically the reason for our whole discussion here and below. And again, even if it holds true in this case, it's not "black and white" and may not be applicable in other species groups. >> >>Or on the same note. Was Burbrink really justified to sink all those subs of guttata, bring back New world "Elaphe" and recognize three species "emoryi", "slowinskii", and "guttata"? >>It was very pertinent that you brought the guttata group into the discussion, a group that ranges from the Jalpan Valley in Queratero, NW to Utah and east to (New Jersey?). >> >>Forks
I'll answer the rest later when I get some time.
Terry
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