Does microevolution logically include macroevolution?

I've often thought the same thing. If someone who had never seen a dog of any kind before were to come across a wide assortment of breeds, would they intuitively think them all to be the same species, or even closely related for that matter? If the breeds they saw covered a significant portion of the spectrum I seriously doubt it.I did a Google and came across this page, and I must say, I never realized just how diverse a group the domestic dog is. I knew there were many different breeds, and I knew they came in many shapes and sizes, but damn... I didn't realize just how odd some of them are! Can't say I've ever seen one of these before. Looks kind of like that brush I use with the dust bin. Honestly, if you'd shown me that photo removed from its context, I'm not even sure I'd have been able to identify it as a dog!But seriously, why exactly are domestic dogs still regarded as just one species? From Wiki's "Canidae" entry, we are shown the following for Genus Canis...Coyote, Canis latrans
Wolf, Canis lupus
Domestic Dog, Canis lupus familiaris
Dingo, Canis lupus dingo
Red Wolf, Canis rufus
Ethiopian Wolf, Canis simensis
Golden Jackal, Canis aureus
Side-striped Jackal, Canis adustus
Black-backed jackal, Canis mesomelasIf you follow the links, most of these have images and, as far as I can tell, there is far, far more diversity among domestic dog breeds than there is among all of their cousins combined.Now, I realize that this is largely due to the artificial selection that humans have imposed on them since their domestication, but is their wide morphological diversity not sufficient to classify modern domestic dogs as multiple species (or subspecies) branched from the initial stock?Is it because their cousins (wolves, coyotes, etc) are further removed from them, in terms of how long ago they branched away, than they are from each other? Or are there, in fact, larger genetic differences, despite their respective appearances? For example, is there actually a greater genetic difference between, say, a German Shepherd and a Gray Wolf than there is between a German Shepherd and a Pekingese?Or, alternatively, we could amend that slightly from the perspective of species. So, with regard to the relative genetics of the given examples and their respective comparisons, is there a greater difference between, say, a wolf and a coyote (which are different species), than between the aforementioned German Shepherd and Pekingese (which are the same species)?I realize that I'm just going on photographs and not the living creatures themselves, and, for the record, I can see differences between the wolf and the coyote... My point is that they seem to have much more in common than many breeds of domestic dog do with each other.Honestly, I could forgive someone for confusing the animals in those two photos... though, to be fair, they have captured them in very similar poses; I might think differently if I saw them both up and walking around. Still, I doubt there is any pose or camera angle that could make me mistake a photo of a German shepherd for a photo of a Pekingese, or vice versa.Something else I've wondered about domestic dogs is whether or not they are all inter-breedable. Obviously, there is the question of the physical practicality of certain couplings, but is it possible to do, even if only in principle? For instance, could you cross, say, a Great Dane with a Chihuahua via artificial insemination? Would it produce viable offspring? And if you could not, or if the offspring were sterile, would this qualify the two breeds as having become significantly diverged to be classified as separate species?As a slight aside, I was surprised to see that even among "True dogs" there are a multitude of genera. Shows what I know. Clearly, I've been mixing up my levels of classification - specifically Canidae and Canis. If I understand the page correctly, all dogs are canines but not all dogs are genus Canis.Also, the article's distinction between "true dogs" and "foxes" is a noteworthy point, itself. I don't know what the current position of biologists/taxonomists is but, if it helps, the page states the following... Ouch! I ramble...This is for anyone, by the way. Asgara simply made the comment that grabbed my attention. All are welcome to answer.

Thanks for the replies, guys.Nuggin, thanks for the link. That's really a dog? Cool! Speothos venaticus... So, it's further removed from the domestic dog than wolves and coyotes, but still within the family Canidae. Well, if you hadn't told me, I would have thought it was some odd kind of bear.

I would think so, too. Though I must admit that I'm not completely clear on exactly what our current usage of "species" is. It seems to me that there has to be more to it than simple morphological differences. There are both organisms which appear very similar yet are different species, and organisms which appear very different yet are the same species. This leads me to wonder exactly how they are classified in the first place. Genetically, perhaps? Is it simple reverse chronology (lineage A split from lineage B... which, further back, split from lineage C... etc)? Indeed. I'd really like to hear from someone in the pertinent fields about this. Can anyone tell me if this is true? Is there actually a larger genetic gap between examples like German Shepherds and Wolves than German Shepherds and Pekingese, despite their respective morphological similarities/differences? So, mere physical incompatibility (despite genetic compatibility) is sufficient, in some cases, to warrant classification as separate species? Perhaps, in the instance of the domestic dog, it is simply a case of convenience, then? Technically, they would qualify as multiple species, but, due to their consistent, close association with man during the centuries (millennia?) of their domestic breeding, we have simply never bothered to class them any differently. Yes, so I've heard. I assume that, in this context, the word "dog" would refer to one that is not so far removed, morphologically, from the wolf... like the German Shepherd I mentioned previously, for example? Somehow, I have a hard time picturing a wolf getting it on with a Yorkshire Terrier. No, probably not naturally (by which I assume you mean "via regular mating, without the intervention of man"). But what I was really wondering was whether or not they are too genetically different to reproduce... hence my question regarding artificial insemination. That is, would their genes be compatible enough to produce viable offspring, in principle, even if the parents could never produce them on their own, due to morphological differences?In any case, if, as you say, the physical impracticality of mating between two nonetheless genetically compatible organisms is enough to classify them as separate species then I suppose the question of whether or not it could be done artificially is moot. Still, I am curious to know. I'd love to hear from any of the resident biologists/geneticists on this. Or just anyone who is familiar with the fields and can answer, really. No, that's not what I was getting at. To be honest, I'm at a loss as to what the definition of "species" is, and I was just wondering how the plethora of domestic dog breeds fit into it. Just to be clear, I don't think that dogs screwed anything up; I think that we screwed up by continuing to class them all as the same species when it would seem, from what I've read, that they have diverged sufficiently enough to be classed separately.I am, of course, still speaking from a position of ignorance, though. I'm careful not to make too many conclusions here because it is still unclear to me exactly what a species is supposed to be.