Re: While I happen to think . . .
by
the true conservative
06/16/2009, 4:12 PM #
In fact, it's not even an example of speciation; the necessary change in alleles doesn't occur with selective breeding. A breed isn't really comparable to a species as regards being genetically distinct. The example I had in mind was an analysis of a geographically split population of mice wherein one population changed alleles within some small number of generations. I'm not familiar enough with the case to comment much more than that; JGC's your poster for more information on that.
Actually, dog breeders do on occasion create new breeds that cannot readily reproduce for phenotypic reasons with other dogs, which is pretty much exactly the same thing as what you are describing. This process is actually pretty common in nature.
The problem is still the same. No new genetic material is created. A stock "mutt" variety contains an astonishing amount of genetic potential for diversification that only shows itself in isolated breeding environments in all animals. These can hybridize so much that the separate lines no longer normally "attract" to each other. But nothing new that did not already exist latently in the genetic code of the parent critters is actually created.
Darwin's famous finches are a good example of this. There are about a dozen different species of them that do not readily interbreed in nature, primarily because of phenotypic differences. But they are all actually fertile together. If they are artificially inseminated, they produce offspring that resemble the parent species - and their offspring are viable and fertile.
Given that we share 90+ percent of our DNA with flatworms and considerably more with our anthropoid cousins
This is a popular myth, but it is nonetheless false. We share 83% of our DNA with the great apes and only about 40% with flatworms.
Of course, we still have to account for he original genetic material, at least when dealing with the question of origin of life. But evolution is an explanation for biodiversity and the particular "advancements" of certain species. Abiogenesis isn't an unrelated field of speculation, but it's not the same field of speculation.
And of course I agree. There are a great number of Christians who accept the theory of common descent (the venerable C.S. Lewis might be the most famous). But philosophic naturalism requires a belief in abiogenesis and nothing but blind chance and random processes to explain the origin and development of life. And that is a position that simply cannot be defended on the basis of the observation that the flu virus mutates to develop resistance to drugs.