True, but I used it in the sense of the claim that the characteristics of the two populations would remain stable. Perhaps a misuse - sorry.
Humans have practiced accidental selective breeding
This indicates that any border between “natural” evolution and “artificial” selection is pretty blurry.
This is just not true. The primary definition of evolution is change in allele frequency in a population. This has indisputably occurred in domesticated dogs. Dogs arose from wolves, and are still considered the same species as wolves. But dogs are clearly different from wolves, both genetically and phenotypically. This is still evolution, even if it has occurred through interaction with humans and through deliberate artificial selection by humans.
Not all evolution is speciation. Separated populations of one species between which there is limited gene flow (dogs and wolves) evolve differently. The allele frequencies in the domestic dog population are obviously very significantly different from the wolf population, notwithstanding the fact that they are still considered one species that could still interbreed (at least there is no apparent genetic barrier, in the case of the smallest dogs there’s probably a physical barrier).
But dogs and wolves are still the same species and freely interbreed. It has been observed that unmanaged dog populations revert to something like the Pariah dog, a sturdy mid sized mutt. The indication is that wolves and dogs may both just be variants of a common ancestor.
And not just in evolutionary biology. There’s clearly one colloquial meaning to artificial vs natural that means something like with/without human intervention or influence.
But I think this part of what @Chronos said is a very valid point, which is not just semantics:
In population genetic terms, evolution under selection operates under the same mechanisms whether the selection is natural or artificial.
Really? That does not mean the same thing as can interbreed.
In any event, the frequency with which wolves and dogs now interbreed doesn’t matter. The allele frequencies of many phenotypically significant loci among modern dogs are very different from the allele frequencies of the ancestral wolf population from which they arose. By definition, they have evolved. Even if you want to add in the allele frequencies of modern wolves and consider dogs+wolves a single interbreeding population, it makes no difference, since the population of dogs now vastly outnumbers wolves.
Yes take your pick
Of course. In fact, modern dogs were recently reclassified to the same species as modern wolves.
Canis familiaris was changed to Canis lupus familiaris.
Thanks, you make my point
Not at all. The point you made that I was disputing was
The correct point that dogs & wolves share a common ancestor, and the recent scientific consensus that in fact the dog & wolf populations have not diverged sufficiently that they should even be considered two separate species, does not remotely imply that dogs have not evolved since they arose from an ancestral wolf population. Evolution is not synonymous with speciation.
Ok, let me spell it out for you. In population genetic terms, “freely interbreed” means no significant loss of gene flow between subpopulations. It means they do interbreed frequently, not that they can interbreed.
I’ve pointed out to you the fact that dogs were recently reclassified to the same species as modern wolves. Of course I know they can interbreed.
Then I misused the term common ancestor. Wolves and dogs are just variant populations of the same species. They may have evolved as a group, but not as a result of artificial selection.
OK, then what nit are we picking?
Correct, that’s the modern scientific consensus. But again, this does not lead to the conclusion that they have “not evolved”. Once again, the word “evolution” is not synonymous with the word “speciation”.
Aha, so I should have better qualified my statement.
How about - the current ‘breeds’ of dog are simply unstable variant populations. They did not evolve.
Well, no. Even if you hypothesize all humans vanishing and a reversion to free interbreeding among domesticated dogs, the “mutt” result is not (genetically or phenotypically) identical to the ancestral wolf population from which they arose. Allele frequencies in the population have changed significantly. By definition, they have evolved.
If you want a specific example - one of the significant ways in which they have evolved (across most if not all breeds) is neoteny.
This is important, and worth fleshing out.
The major difference with artificial selection is that the selection is extremely strong compared to most natural selection (not without exception, obviously sometimes there are quite drastic environmental changes such as asteroid impacts). So what it can do, artificial selection does very quickly. But selection can only act on the genetic variation that’s available, it cannot cause new mutations to arise - that’s Lamarckism. So artificial selection operates on the standing genetic variation that already existed within the natural starting population. Artificial selection can change some aspects of phenotype very quickly - turning a wolf into a Chihuahua in a few generations. But then it hits a brick wall. Any further change by artificial selection would mean waiting for new mutations to arise by chance. And that just won’t happen in timescales that humans are interested in.
To chime in on this, even the poster-child (chick?) of islandised speciation, the galapagos finches, can (and do ) interbreed. I’m sure we still would assert that they have evolved from the initial population.
I was hasty to imply that the Pariah mutt is a reversion to the original.
There is no indication that dog family has evolved. The allele frequency has not changed. The basic allele schema have not changed. The same variant paths are available today as were at the time of domestication. That is illustrated by the Pariah mutt.
If dog variants had evolved they would be stable. They are not.
Perhaps you are referring to a background evolution that is related to, but not the direct result of, human intervention.
Cite, please. This is ludicrous on its face. You think the dramatic change in lifestyle from wild wolf to domesticated dog has resulted in no change in allele frequency in the modern dog population when compared to the ancestral wolf population from which dogs arose?
I don’t know what you mean by these things. This is not standard terminology.