didymus:
Evolution isn’t the theory – evolution (change over time) is a fact, clear from the record. Darwin’s theory and later refinments is “natural selection” as the mechanism by which evolution occurs. Certainly it can’t be tested the same way a that a theory of physics can be but that’s true of biology generally.
Lets keep our terms straight. It is a circular argument to use Natural Selection to try to prove geneticly incompatable specization by calling both ideas “evolution” and then declaring that since one idea is proven the other is as well.
Additionally, the “biological species concept” of identifying as separate species diverse but still cross compatable “species” (e.g. dogs and wolves) does not “prove” (and actually contradicts) the idea that sufficient genetic drift can account for non-cross-compatable genetic specization.
In the cases where we have a broadly diverse gene pool of individuals with an established common lineage (no “missing links”) and significant adaptation in regionalized groups, they have all maintained genetic cross-compatability even when adopting substantially differenet genetic adaptations and even diets and social structures.
There is no evolutionary advantage to be found in losing compatability with other decendants of the same parents. However, maintaining a larger avaialble genetic pool for mates is a safeguard against losing a local advantage of adaptation to a regional natural disaster.
I already mentioned the dog/wolf compatability, but that cross compatability among the canines extends to the coyotes, foxes and other niches canines with each other and the entire spectrum of domestic breeds.
The large cats (lions, tiger, cougars) all maintain cross-compatability, and there are documented bobcat/housecat grosses and crosses of bobcats with other larger cats, it looks like the entire feline family has retained genetic cross-compatability across multiple continents.
The cichlids in various African lakes (currently the targets of a naming frenzy by taxonomists) have, despite geographic isolation, retained cross compatability between both specialist groups in the same lake but also from lake to lake.
Killer whales have recently been determined to actually ahve two parallel, non-competing social structures. One group eats fish, the other red meat, and they “speak” differnetly and do not inter-breed as a matter of practice, but can and will “under duress”.
And to further cloud the issue, as more of the fossil record unfolds, population groups long held up as genetic “dead ends” that were incompatible with “sister” species of common parents and died out have instead been shown to be able to interbreed and thus were not examples of incompatible speciesization. The Neanderthal, long presented by the “pure” evolutionists as such an example, have more recently been established ot have co-existed and interbred with the “modern” human lineage. It turns out the Neanderthal were not an incompatabile species “proving” specization within the human gene pool, but were instead just an identifiable “minority group”…
And that’s the pattern we keep coming to, over and over again. Find a set of sexually reproducing isolated groups (of male and female individuals) with verifiable and undisputed common parentage, and for some reason they have retained genetic cross compatability through the course of their adaptations. We might
imagine relations between groups in the fossil record based on physical characteristics, but so far our ability to backtrack adapted groups of known common lineage speaks
against natural selection leading to geneticially incompatibile specization.
