Yes I do know that they are cross species reproduction and I also know that the mules and jennies are sterile. They therefore have no bearing on the discussion.
As for the dog breeding you suggest I have heard of successes of such pairing. (With the male being the smaller dog)
It is estimated that man was on the American contents 10,000 years (I read an article recently that upped that to 16,000 years) before the Europeans arrived with a conservative generation of 20 years that is 500 generations. That is not huge on the evolutionary time table but not insignificant. Name a significant trait that natural selection produced in humans on the North or South American Continent.
Those ~10,000 years of separation produced the differences between indigenous Americans and Asians that we see. 10,000 years is a lot less significant than you appear to think, on an evolutionary time scale. It took six million or so years to produce the differences we see between humans and chimpanzees - that's 600 times as long as the time scale you mention (at least 300,000 generations, probably more).
Speciation is such a slow process that we don't expect to observe blatant examples of it happening in observable time spans (such an observation would be evidence against our understanding of evolution). What we do expect to see are species in the process of evolution, which are observed all the time. Geographically extant ring species are prime examples of a 'freeze frame' of evolution in action. They're one species (sort of), that could easily become two species if a minor extinction event took place somewhere in the ring.
Very small body size in the Amazon; barrel chest and high lung capacity in the high Andes; cold adaptation, including slight relocation of forearm veins and arteries, in Tierra del Fuego.
They help keep you alive and thriving when all you have to eat is meat or fish, the night is 24 hours long (requiring you to see in the dark), and it's really cold!
Up until the Middle Ages the Polar Peoples were physically isolated from all but the most intrepid outsiders.
I assume you mean hinnies? It is generally true that mules are sterile but it is not universally true. According to this
Since 1527 there have been more than 60 documented cases of foals born to female mules around the world.
Yes I do know that they are cross species reproduction and I also know that the mules and jennies are sterile. They therefore have no bearing on the discussion.
Jennies are not always sterile. Which has a direct bearing on the conversation. Mules and Jennies asymmetric reproductive capacities are a living example of speciation caught in midstream. There are many others. See ring species. see Ligers.
As for the dog breeding you suggest I have heard of successes of such pairing. (With the male being the smaller dog)
Uh, huh. But not the reverse? And you don't draw the painfully obvious conclusion? I'd like to see pictures of a teacup poodle covering a great dane.
It is estimated that man was on the American contents 10,000 years (I read an article recently that upped that to 16,000 years) before the Europeans arrived with a conservative generation of 20 years that is 500 generations. That is not huge on the evolutionary time table but not insignificant. Name a significant trait that natural selection produced in humans on the North or South American Continent.
Red skin pigment. Susceptibility to smallpox and measles.