Well, put a collar on me and call me a bloodhound. It seems that dogs aren't wolves after all. Darren Naish, of Tetrapod Zoology, discusses a whole range of recent literature and the arguments for and against in a truly excellent post.
The arguments against note the morphological and behavioural differences between domestic dogs and wolves, and the fact that dogs when feral seem not to backbreed into wild wolf populations, a sure sign (well, relatively sure) that the two are distinct species. However, there has been some crossbreeding, which is what one might expect if dogs and wolves are sister species. As it happens, there are two wolf species, the Canis lupus of northern Europe and America, and the Canis lupus pallipes, the Indian peninsular wolf. So where did Canis domesticus come from? Naish reviews the evidence that it is from the Asian pariah dog, of which the New Guinea singing dog and the Australian dingo, introduced here around 5000 years ago, are subpopulations.
I find Naish's argument convincing. Dogs have a different, more malleable, hierarchical pack structure than wolves, in which only the dominant pair breed, and they share food more than wolves do, which would make them good partners for packs of humans. Wolves are also not trainable, though they can be tamed. But I wonder if domestic dogs are in fact a fourth species of canids, closely related to the pariah dogs of Asia, which were pre-adapted to being hominid companions. And I also wonder if they were in fact domesticated, after a fashion, by coevolution with Homo erectus, which we know existed in Asia for the duration of the very long period posited for the domestic dog by one of the research teams Naish cites.
One of my favourite malapropisms - "monophyletic clade" - is also used by Naish self-consciously. This is a killer site. Everything from crocs to dinos.
- Log in to post comments
I like his stuff too, but man, those posts are LONG!
Thanks for this. I own Schipperke's which appear more 'fox' like than wolf like and their breed origin is unknown. I suggest that there maybe a realationship with foxes as well since they are also a species of canids.
Well there's African wild dogs, hyenas and coyotes as well, but I was referring to those in Asia at the time. I don't think there are any other species of canid in Asia...
It was an interesting read. I am not a biologist so the fact that I find some of arguments less than convincing probably means little. However, I see a little too much ad hoc argument and assumption. It will be interesting to see how the ideas play out. I love dogs but am not invested in the dog-as-wolf concept.
He could have discussed this article a bit more:
Savolainen, P., Zhang, Y.-p., Luo, J., Lundeberg, J. & Leitner, T. 2002. Genetic evidence for an east Asian origin of domestic dogs. Science 298, 1610-1613
Now the reference was only passingly mentioned. However, this study has two of the same authors as Vila et al.'s 1997 study and seems to indicate that they have revised their estimates somewhat (instead of 100 000 years, dogs might have originated 40 000-15 000 years ago).
It still doesn't tell us whether dogs originated in East Asia from wolves or some other species, but perhaps it is not fair to cling to the 100 000 year date. As we now know mtDNA is not a very good neutral marker, anyway.
I believe that Hyena's are more closely related to mongooses than dogs. Another example - with the tasmanian wolf - of convergent evolution.
Hyenas are closer to cats than to any other living carnivore clade.
>> As it happens, there are two wolf species, the Canis lupus of northern Europe and America, and the Canis lupus pallipes, the Indian peninsular wolf. <<
The Indian wolf's formal name tags it as a subspecies. The number of wolf species depends on how you define "wolf." There are at least two species of wolf: the gray wolf (Canis lupus) and the probably-extinct-but-who-really-knows red wolf (Canis rufus). Some genetic data suggests that the "timber wolves" of eastern North America were a third species, closer to the coyote (aka brush wolf, Canis latrans) and red wolf than to the Old World's gray wolf.
Naish's argument is interesting but contains some holes, since his primary source seems to dramatically understate the resemblances between dog behavior and gray wolf behavior. I've read a lot about wolves, and I've lived with dogs and with a wolf-dog hybrid, and dog and wolf really are a _lot_ alike. Most of the differences between dog and wolf can probably be accounted for as adaptations to the highly specialized niche that dogs have come to occupy.
I'm getting very interested in canid taxonomy now. Thanks for this. Can you suggest a reference?
As I noted there, my (inexpert) understanding about the crossbreeding issue, was that the dog/wolf hybrid has a mating season that doesn't overlap with the pure wolf's. I have no idea what the "ultimate" significance of this is.
Huskies and Aslatians certainly have some wolves in their background, because there have been regular purposeful crossbreedings. That said, recent wolf blood in a dog does seem to have dire effects on their psychology, and the direct hybrids at least have noticably different "social behavior".
There's also that Siberian group that has produced "domestic foxes" simply by breeding for docility. The interesting thing is that the stock has developed a lot of physical features which are characteristic of dogs, and especially of the "pariah" types.
John,
Canid taxonomy is a bit fluid these days, what with all the revelations from genetics. The best informal book reference I can think of is FOXES, WOLVES, AND WILD DOGS OF THE WORLD by David Alderton, c. 1994. There's a useful summary of the wolf/coyote classification muddle in Wikipedia's entry for "Red Wolf". For a quick informal summary of the evidence connecting wolves to domestic dogs, see Chapter 2 of The Truth About Dogs by Stephen Budiansky, c. 2000. Budiansky has a somewhat unconventional view of domestication: he believes "domestication" was essentially an evolutionary, selective process that happened by chance, not by choice. In his version of events, the presence of proto-humans created new ecological niches and animals which had the right combination of traits to exploit those niches, did so in a classic evolutionary manner.
"The Truth About Dogs" is a good read and I find Budiansky's explanation pretty convincing. Dogs were wolves (most likely) that adapted themselves to following humans around and eating their garbage etc. This tended to encourage traits that would endear the animals to humans or, more precisely, discourage hostile reactions. This continues today. In many, if not most, parts of the world, dogs are seen as tolerated vermin rather than pets. This was the ecological niche that dogs filled and only subsequently were they adopted as pets or work animals.
I thought the clincher regarding the dog-wolf relationship was genetic. Dogs are far more similar to wolves genetically than any other canine. If I remember correctly, Budiansky talks about this at some length. But perhaps it is not as true as I thought.
Anyone else see today's Bizarro?
Those lazy wolves who said -- "the hell with chasing elk around and getting bucked in the teeth and shit, I'm going to sponge off the humans" -- are my spiritual ancestors.
Now that I think about it, Budiansky wrote a whole series of books on things related to evolution, humans, nature, and domestication:
The Covenant of the Wild (1992) explains his theory on domestication in general terms.
Nature's Keepers (1995) is a tract on ecology, environmentalism, and how humans should (and shouldn't) try to "manage" wilderness areas.
The Nature of Horses (1997) is an extended look at horses -- history, origins, biology, etc.
If A Lion Could Talk (1998) looks in some detail at the issue of "intelligence," what it is and what it isn't, and how simple behavioral rules can give rise to complex behaviors that look intelligent.
The Truth About Dogs (2000) is a detailed look at dogs: origins, breeding, behavior, intelligence.
The Character of Cats (2002) does for cats what the previous book did for dogs.
In about ten years of reading extensively about evolutionary theory, I've encountered two or three "science writer" types who seem to grok the full implications of evolution by natural and sexual selection better than many scientists do. Budiansky is one of them. At his best he reminds me of Jonathan Weiner's magnificent The Beak of the Finch, or John Noble Wilford's classic The Riddle of the Dinosaur. I recommend them quite highly.
Re my last comment, you'll have to pick the 12th out ouf the drop down menu, or the comic won't have any relavance. Sorry, there is no solid url.
Hey! That NGSD looks like mine! And I agree, great reads at Darren Naish's site :)
I love that you provide us with this information. Thank you soooooooo much. It helps a lot!!! You guys and gals rock. Continue to give us more awesome information and simpler words, though I did seem to understand, but thanks anyway!!! :)
Me and Nicole are bff's. she is the best friend I have ever had. Although she has been hanging a lot with her bf lately, I still love her and I miss hanging w/ her!We have been best friends since kindergarten all the way to college. So we had our fights, but we always end up being friends again. And thats what true friends do. I love her soooooooooo much. If you are reading this Nikki or Nicole, this is Leah or Bethany. I love you girl. I called you to read this.If you do type back. No one better comment about this. cause i have a ot to say about you guys', but some were great. Way to go!!! :) smile Nikki.I love you as a bffaaudpuask or whatever. Bye,Bye girl. type back.:)........... I miss you Nikki and I am willing to tell the world!
buy the way nikki, I did #17 and #18. check it out. you'll love them................. hopefully. t/b!!! please. :) love you gurl!
I provisionally accept that the ancestor of dogs was a canid that was already distinct from C. lupus. The arguments seem reasonable to me.
No dogs are descended from foxes. Foxes are in different genera (Vulpes plus a couple others) from dogs, wolves, jackals, etc (Canis). They cannot interbreed.
African wild dogs, while looking dogish, are also in a different genus (Lycaon) although Canis may be polyphyletic with respect to this African Wild Dogs.
Wolves are relatively frequently bred into Alaskan Indian Village Dogs, Labrador Inuit Dogs, and Canadian Eskimo Dogs (supposedly to improve stamina). These dogs do occasionally kill people. There was a recent instance (within the last few years I think) of a musher breaking a trail in front of her team in a race and being set upon and killed after she fell in front of them. There is also an interesting document about local dogs by a physician who spent time working in Northern Labrador in the native communities around the turn of the last century. Apparently it was not too uncommon for people to be attacked and sometimes killed (and eaten) by the dogs (though not by the wolves).
It would be interesting to know how much of the native North American dogs owe to Canis lupus compared to old world dogs.
In Canada there has been a fair amount of effort expended on determining the status of Eastern Wolves since they are of conservation concern. This is one of those things that I have been meaning to thoroughly read up on but I have not had the chance yet. Basically there are four potential Canis sp. at issue (excluding domestic dogs): C. rufus (Red Wolf) which is (or was) found in the south eastern US, C. lycaon (Eastern Wolf) which is found in Ontario (most famously in Algonquin Prov. Park), C. latrans (Coyote), and C. lupus (Grey Wolf/Timber Wolf) which is found in Europe, and North America (now north and west of C. lycaon). My understanding is that C.rufus and C.lycaon cluster together in most phylogenies and form a sister group to Coyotes. Introgressive hybridization with Coyotes is a major conservation problem for both of these species. Anyway, these three have evolved in North America for millions of years. North American C.lupus are descended from a more recent reinvasion from Europe across the Bering land bridge. The situation that we have now is that (basically) C.lycaon occupies the northern mixed forest (but generally south of the boreal forest), C.rufus the southeastern U.S. (but now almost functionally extinct), C.lupus the western mountains and foothills, the west coast forests, the prairies (but mostly extirpated from there), the boreal forest, and the tundra all the way across. Coyotes were previously restricted mostly to the prairies but deforestation and extirpation of wolves (of various varieties) has allowed a huge range expansion that started in the 1800's and hit the easternmost parts of Canada in the 1970s (they got to the east coast in the States a while ago). As their range has expanded their morphology has converged on that of C. lycaon and here in Ontario they are about 30% heavier than their western ancestors and predate extensively on Whitetail Deer (unlike westerners that stick mostly to smaller game). It is unclear to what extent the morphological and behavioural changes are caused by natural selection + phenotypic plasticity (Coyotes are notoriously adaptable) and how much of it is due to introgression of C. lycaon genes. As it stands now, C.lycaon is extirpated from most of their range (which is now occupied by big Coyotes) and these wolves and Coyotes now meet at a contact zone between the more heavily populated Southern and central Ontario and the more heavily forested north (at about Algonquin Park). I'm not sure what happens at the contact zone between C.lupus and C.lycaon. Anyway, unlike wolves, Coyotes do very well around people (including in urban areas). I suspect anthropegenic changes is causing a reversal of incipient speciation.
And then there are the Mexican Wolves...