Are dogs direct descendants of wolves?

[Blake]

@Darwin_s_Finch

And while sure, these little yellow dogs may look superficially similar, what studies have been done which actually compare the freezing island variety to the hot savanna variety?

What sort of studies do you want?

As we all know, superficial similarities can be deceiving. Just because they share similar body types doesn’t mean they are all converging on the same ancestral form.

Of course not. The point is that they do all converge. That is, I would hope, indisputable.

The question then becomes why they converge. If they were just evolving in response to environment and founder genetics, as you claim, then we would predict that they would not converge because founder genetics and environment varies so wildly between convergent forms.
If it is not convergence on an ancestral form, and it can’t be convergence due to founder genetics and environment, then what is it converging on?

The body type could well be developmentally constrained as a result of generations of selective breeding.

I don’t understand. Some dogs are more closely related to some wolves then to other dogs. Yet all dogs revert to yellow dogs. So how can the yellow dog phenotype possibly be constrained by selective breeding in dogs, when it isn’t constrained in the more closely related wolves?

Further, we don’t always even know which domestic varieties of dogs are the ancestors to these feral populations, so we can’t really be sure what we are looking at one way or the other.

Unless you are positing that a Congolese village dog, ad Pakistani patriah, a Carolina dog, a dingo and a feral dog in New York all amazingly share a common heritage then we do know what we are dealing with. We are dealing with dogs from a range of genetic provenances.

Yet they all converge.

It could be that the “ancestral breed” was a little yellow guy, and that little yellow guy could, in turn, be derived from wolves.

But it’s turtles all the way down. So this doesn’t actually seem to adsress anything. If dogs are capable of reverting to the last common dog ancestor, why doest it stop there? Why don’t they keep reverting all the way to the wolf ancestor, with which they have constantly interbred until just afew hundred years ago?

The point is, we can’t really backtrack sufficiently for this to really tell us anything about the ultimate wild ancestor of the dog because there’s an awful lot of shared morphological similarities between dogs and the potential ancestral candidates.

Yes, and there are a lot of differences. too.

Granted, there have been many studies which start with wolves (or just assume wolves as the ancestor) and examine the genetic similarities between dogs and wolves and, of course, they have been shown to share a good deal of genetic similarities. Have such molecular studies been done with respect to the other potential candidates…? If not, it would seem like that could go far in untangling the phylogenetic mess.

The problem is that it is a mess. I can show you papers, all published in the last 10 years, all based on genetics. One argues that the red wolf is a distinct species at least 1/4 million years sold. One that it nothing more than a starin of grey wolf, one that all red wolves are simply the result of a grey wolf mating with a coyote. Similar is true of the status of the Asiatic wolf or the Dhole.

When we can’t even work out how many species of wild canids exists today, when we have thousands of living animals to take genetic samples form, there is no way in hell we are ever going to identify an extinct animal from 40, 00 years ago based on a genetic legacy in a crossbreed.

Imagine that the sole ancestor of the dog was a Eurasian red wolf, and that dogs had never, ever hybridised with grey wolves. And we discover a living specimen tomorrow. According to some experts that would mean that the ancestor was definitely not a grey wolf. According to others it would mean that the ancestry was a mixture of wolf and coyote, while others would declare that the ancestor was indisputably a grey wolf. And we get that mess when we have living animals to test.

Now imagine the impossiblity of identifying an extinct red wolf type animal in there given that dogs and grey wolves have been constantly hyrbidised over the millennia.

This isn’t a question that is ever going to be answered genetically, unless perhaps we find a mummified specimen of the ancestor and it provides a 100% match for all known dog genetics. Which seem a little unlikely.

[TriPolar]

After looking at all the facts and speculation in this thread, it doesn’t seem difficult to explain the state of the canids. Variant forms of a common ancestor diverged in isolation, but then began mingling again before becoming distinctly different species. The success of the grey wolf line may have been the means of spreading genes through other canid forms around the world, and explain why all of them have wolf characteristics. For all we know, the present day types are all hybrids of extinct animals, including the little yellow dog.

[DSeid]

@Blake

Only to somebody who knew nothing at all about dogs.

Amazingly enough I know a fair amount about dogs and disagree.

Funny that.

That animal has a broad snout? Not the picture I’m looking at.

As far as color goes - interestingly enough (behind wall I suspect sorry), grey wolves seem to have picked up the gene for darker color from domestic dog populations.

We show that the melanistic K locus mutation in North American wolves derives from past hybridization with domestic dogs, has risen to high frequency in forested habitats, and exhibits a molecular signature of positive selection. The same mutation also causes melanism in the coyote, Canis latrans, and in Italian gray wolves, and hence our results demonstrate how traits selected in domesticated species can influence the morphological diversity of their wild relatives.

As far as the genetic evidence of a wolf origin - again - it is established beyond any reasonable doubt to those who are experts in evolutionary genetics. The open question is only the exact timing. Or timings. (Again sorry if this turns out to be behind the firewall.)

We analyzed the genetic variation in 582 base pairs (bp) of mtDNA in 654 domestic dogs from Europe, Asia, Africa, and Arctic America and in 38 Eurasian wolves (13, 14) (tables S1 and S2; fig. S1). It has previously been shown that domestic dogs originate from at least four female wolf lines (2, 15). Phylogenetic analysis of our data assigned the dog sequences into the same four phylogenetic groups (clades A, B, C, and D) and to a fifth “group,” clade E, consisting of an isolated haplotype (Fig. 1 and fig. S2) (14). These groups were interspersed by wolf sequences and were approximately equidistant from a cenancestor of all wolves and dogs. Therefore, we conclude that the domestic dog population originates from at least five female wolf lines. Furthermore, although not separated from clade A by wolf sequences, a sixth group, clade F, is suggested by the separation distance. In the following analyses we will treat these six groups separately. Clade A included three wolf haplotypes found in China and Mongolia; clade B contained three wolf haplotypes, two found in East Europe (one of which is identical to a dog haplotype) and one in Afghanistan (fig. S2). This suggests an origin of clade A in East Asia and of clade B in Europe or Southwest Asia. However, wolves are extremely mobile, resulting in little geographic partitioning of mtDNA haplotypes; Vila et al. found identical sequences in a Bulgarian and a Saudi Arabian wolf, as well as in a Mongolian and another Saudi Arabian wolf (16). Thus, the finding of a few wolf haplotypes closely related to domestic dog types is not in itself a sufficient basis for establishing the location of domestication.

So let’s see … do I believe your claim that all feral dogs look alike and all look nothing like the smaller wolf lines, or my own eyes, and the experts in evolutionary genetics?

It’s not really a tough one.

[clairobscur]

@TriPolar

along with a brain that functions in some distinctly different way.

Could you elaborate?

[Blake]

@DSeid

Amazingly enough I know a fair amount about dogs and disagree.

Well this is easy to settle. take me up on my challenge. You post a dozen B%W photos of dogs, all of them from either an established “yellow dog” lineage or an Arabian wolf. And if I don’t do better than 95% accuracy at picking which is which then I’ll concede your point.

Willing to take me up on this? Because if you aren’t then quite clearly these animals are instantly and perfectly separable from Arabian wolves even to cursory visual inspection.

So let’s see … do I believe your claim that all feral dogs look alike and all look nothing like the smaller wolf lines, or my own eyes, and the experts in evolutionary genetics?

1. Who has ever claimed that all feral dogs look alike?

2. Which experts have made reference to whether any dogs lshare the same phenotype?

[DSeid]

Blake, uh no. I do not have access to and have no interest in finding a dozen or more pictures of “an established ‘yellow dog’ lineage”, think your challenge is a silly one at best, and fail to accept the second grade level taunt of “if you don’t do this silly thing then it is proof I am right!” I won’t and it isn’t. Neener me if you want.

As to your two other points: the logic of your “argument” is that the haplotypes and mitochondrial data be damned, when dogs “revert” to a feral “wild type”, they revert to a “yellow dog” achetype with phenotypic similarity, This alleged feral achytype is not similar to the big grey wolf, so, you believe, the big grey wolf is not the common ancestor. So the answers are:

1. You are making the claim that I am discussing. And,

2. No experts have made that reference, to my knowledge anyway. Just you.

[DSeid]

OTOH Blake is a challenge that actually makes sense:

Find me some morphometric data on skull shape and body habitus of various feral dog populations, a variety of established breeds, and of the Asian wolf. If the data show that various feral populations end up with morphometrics in a very narrow band and that that band is farther from the Asian wolf data than it is from the various contributor breeds, or even a mean of those breeds, then I’d concede your point.

“Willing to take me up on this? Because if you aren’t then quite clearly …” Ah nevermind.

[TriPolar]

@clairobscur

Could you elaborate?

I’d love to. If for nothing else to stay out of the fight over what is or isn’t little, yellow, or a dog.

To start, I have nothing but speculation and assumptions to work from. I even used the weasel word ‘function’ in my statement to keep from being specific. There’s no way to tell the difference between the ‘hardware’ and ‘software’ in a dog’s brain, or how breeding has changed the behavior in dogs.

What I have to speculate from are the studies of intelligence in dogs and wolves, the different physical form of their brains, and comparisons of behavior to other canis types. Wolves appear to have superior problem solving skills than dogs. Dogs seem to learn faster, having a natural motivation to please humans, but wolves are reported to solve more complex problems, where dogs give in more easily. Dogs overall are more cooperative than wolves, with humans, and other dogs. Wolves have the behavioral traits of apex predators, highly territorial, small close knit families, and a strategy of going after the largest prey available. Dogs will easily form packs with unrelated dogs, and different breeds, and usually go after smaller prey. Dog’s brains are smaller and have a different shape than wolves, and this relates to differences in the cardio-vascular system and less dependence on the brain for survival. Wolves also have a number of strong scent glands, and use scent for identification of their family members. Marking territory is done differently for wolves as well, with dogs seeming to use marking as a form of communication. The behavior of dogs conforms better to the dhole than wolves. Dholes are more social, form packs of unrelated individuals, and like dogs display a better temperment in human terms. I don’t know specifially why dholes are considered a distinct species aside from unique dentition. I’m not saying dogs descended from dholes either, they just make a good way of differentiating behavior. All in all, the differences between wolves and dogs could be the result of differing genetics developed for different social structures and survival strategies.

A little more detail on brain size. It doesn’t correlate directly with intelligence, but as dogs get smaller, their head and brain gets proportionally larger in comparison to the rest of their body. The dog brain is not something simply scalable in size. This indicates to me that dogs have genetics to optimize brain size to something different than wolves.

Slightly off topic, I haven’t inserted one my favorite quotes in this thread:

“Outside of a dog, a book is a man’s best friend. Inside of a dog, it’s too dark to read.”
Groucho Marx