Original site of Dog domestication questioned
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(Disclaimer: although I am a dog lover and a wolf fan, I am not a biologist or animal behaviorist. I thus concede that my opinions are just that, opinions, and what seems logical or what makes "sense" may have nothing at all to do with actual events.)
My thing is, I don't think these things have to be mutually exclusive. Domestication need not have occurred only once, and in one way. The self domestication thing is intriguing and I think is very likely. But who knows? People could have still nabbed wolf pups from dens because they were cute, or found them abandoned, or killed their mother and then found the babies and tried to raise them... and these things could have happened over and over and over again! Just because from a technical standpoint wolf pups are only "domesticatable" before a certain point and it's very labour intensive...to me these seem like a dog behavioral biologist impressing his own experiences on the available data, which admittedly is very circumstantial.
It's interesting that barking itself is one of the supposed markers of domestication, along with floppy ears, smaller brains/heads/teeth, more spotty colors, and so on. IIRC, the guy that did the experiment on foxes in Russia (ironically, to make a more docile animal that wouldn't attack the people who were about to kill it for its fur) found that as he "domesticated" the foxes, barking was one of the first things he noticed in the adults, along with the other "puppy-like" qualities, I guess you could say.
One of the things I find interesting about the early dog-human relationship is that the DNA in the dog bones of pre-Columbian Native Americans show them to be of Old World origin.
In other words, Native Americans did not domesticate dogs in the Americas from local wolves; they brought their dogs with them when they came.
Here's an interesting article with some info:
Interesting article Garp -- thx.
As it is said, Dogs have owners; Cats have staff.
Really though, you'd think they must have been either domesticated for either ritual or pest control purposes. Not to break the hearts of the cat lovers out there, but I can't really see them serving any other use, at least to newly sedentary human populations.
"Food" may seem an easy reach at first, given all the jokes about their relation with Chinese food restaurants.... but to this I say... anyone who's ever tried to catch a cat off the top of their shelf after it has knocked everything onto the floor knows that there are MUCH easier things to eat... :-D
But I think I read somewhere else recently - probably After the Ice - that the domestication probably commenced with the dogs being a food source rather than man's best friend.
I don't recall the basis on which Wade made his claim.
(I looked back at the dingo discussion. He refers to the dingos coming with the first people to Australia as semi-domesticated. Perhaps that is the difference. I didn't see what he was relying on for that).
The idea of dingos coming "semi-domesticated" with the first Australian humans: could he mean in the form of wolf ancestors? But that wouldn't make sense either, because the dingo is thought to have evolved from wolves in Asia, and then to have entered Australia as fully a dingo (~5000 years ago). So I'm still not able to sort that out completely.
Agreed, so I don't think the animal in question could have been a dingo, unless there's something I'm missing.
Crows are another creature I think of as semi-domesticated, especially after learning that they can recognize individual human faces.
Now a meat-eating pack animal that sees humans and a source of food, either as prey or scavenging from carcasses humans have killed could be dangerous to have around. I think only the humans consistent success at leaving meat for them to scavenge would keep the humans from becoming prey.
When I was a teenager in rural Ohio for a time we had a pack of dogs that gave up scavenging and was taking calves from local farms so the hunting instinct is not gone. Mooching off humans is just easier.
My boxer was back to the scavenger stage after getting separated from her humans, luckily we humans are very wasteful and she survived long enough for the boxer rescue group to find her.
edit: My profile picture is of my former scavenger, Jinx.
the 15,000 date had to do with the full domestication of dogs from wolves, no dingos mentioned. sorry the above was unclear!
by the way, not that I'm citing him as having the last word on this - I would have no idea about that. I just mentioned it because I'm reading it now and he had something to say about it. You all have much more learning on the subject than I.
The Dingo (Canis lupus dingo) is a domestic dog which has reverted to a wild state for thousands of years and today lives largely independent from humans in the majority of its distribution.
I read Wade and loved it but i can't clearly recall the dingo discussion at all.
However Coppinger also lays out his idea for how wolves essentially domesticated themselves by scavenging in humans' midden heaps; eventually they would have evolved in a way (and relatively quickly) that favoured the smaller, less wolfy looking ones, since people would be more likely to chase the dangerous ones off, AND they wouldn't have to be as big anymore since they'd no longer have to take down big game. This also seems like as good an idea as any to me, and likewise the kind of thing that could have happened all over the place. Essentially, wherever there were humans in any concentration (perhaps even more sedentary hunter-gatherer groups) there would have developed dogs.
It would be great if we could somehow isolate the "dog gene" as it were, but it seems that they have mixed back in with wolves so many times over the years, that it's extremely unlikely to find any divergence point that is old enough to have been the original point when wolves became dogs for the first time.
So original single source domestication always made the most sense to me. And yet ... there is a lot of conflicting evidence -- even with pretty thorough DNA studies -- to suggest that there is still a lot we don't know. For instance, some studies posit that domestic dogs go back 100,000 years! Another study is firm about 16,000. Sounds like there is a long way to go on this yet.
For whatever it's worth, Dawkins in The Ancestor's Tale -- which I'm reading right now -- seems comfortable that domestication probably occurred multiple times in different regions (I just went back to the page to verify & refresh my memory -- it's a huge, dense book!) and he has some serious cred in evolutionary biology.
Still, I'm willing to wait and see ...
So naturally I pulled Wade off the shelf. He says the earliest dog bone that has been found is a mere 14,000 years old and that while some studies have suggested dates as early as 135,000 years (!!!!), he favors the mitochondrial DNA evidence that points to 15,000 years ago, which is why he is convinced of single origin -- Wade tells us that the other theory of three separate domestications would have to require a date of 40,000 years ago and again no fossil evidence shows up until 14K BP.
I also didn't realize until re-reading this section (pp.110-113) that all canid (wolves, coyotes, jackels, dogs) species can interbreed!
Same species, but apparently not possible to distinguish the dingo from other members of the species until 5000 or so bp. A population of dog isolated from other dogs since that time.
"Proc Natl Acad Sci U S A. 2004 Aug 17;101(33):12387-90. Epub 2004 Aug 6.
A detailed picture of the origin of the Australian dingo, obtained from the study of mitochondrial DNA.
Savolainen P, Leitner T, Wilton AN, Matisoo-Smith E, Lundeberg J.
Department of Biotechnology, Royal Institute of Technology, SE-106 91 Stockholm, Sweden. email@example.com
To determine the origin and time of arrival to Australia of the dingo, 582 bp of the mtDNA control region were analyzed in 211 Australian dingoes sampled in all states of Australia, 676 dogs from all continents, and 38 Eurasian wolves, and 263 bp were analyzed in 19 pre-European archaeological dog samples from Polynesia. We found that all mtDNA sequences among dingoes were either identical to or differing by a single substitution from a single mtDNA type, A29. This mtDNA type, which was present in >50% of the dingoes, was found also among domestic dogs, but only in dogs from East Asia and Arctic America, whereas 18 of the 19 other types were unique to dingoes. The mean genetic distance to A29 among the dingo mtDNA sequences indicates an origin approximately 5,000 years ago. From these results a detailed scenario of the origin and history of the dingo can be derived: dingoes have an origin from domesticated dogs coming from East Asia, possibly in connection with the Austronesian expansion into Island Southeast Asia. They were introduced from a small population of dogs, possibly at a single occasion, and have since lived isolated from other dog populations."
If early dog domestication date, why not archeologic evidence for dogs coexisting with humans during 100,000 to 15,000 BP?
Much more to say on this fascinating topic, but I'm leaving town for the weekend. Bye--
And yeah Garp, that very "interbreedability" is what muddies the water so much! Most scientists favour a direct wolf-to-dog lineage, but considering the fact that all the dogs in my house are perfectly capable of mating with coyotes (well they could if they weren't neutered :-D) it seems to me at least probable that some coyote or fox or other DNA has crept in there at some point...
By Adam Miklósi. He traces the genetic and archeologic evidence, including the arguments for an older dog domestication. I wish I could quote from Google books, but I don't know if there is a way. The response to my question "If earlier, why no dog finds a human sites before 15,000 BP?" seems to be "Maybe dogs were not morphologically distiguishable from wolves during the early period of domestication." I find this a dubious claim, as we see that the morphological changes (consistent with neotony) are part of alternate genetic hormonally-mediated programs that can emerge quickly as in Dmitri Belyaev's work. Miklosi supports a late introduction of the dingo into Australia, and a likely 15,000 to 20,000 BP date for dog domestication, though he admits the issue is not settled.
I'm not seeing much support for the Wade Assertion.
The author is clearly in the "they domesticated themselves" camp.
#13 - I also was under the impression that wolves didn't bark, but I was watching a documentary on wolves and was quite surprised to see and hear them barking in a quite dog-like manner to warn off a bear. This was quite a while back and the only two things I now remember about the documentary are the wolves barking and my exasperation that the commentary didn't comment on it. The sound was a little lacking in power and resonance compared to, say, a German Shepherd, but there was nothing about it that would have struck the attention had you not been able to see what was barking - 'just a dog barking'.
Could it be that such a symbiotic relationship went on for tens of thousands of years with the wolves physically unchanged, with imperatives for changes that could show up in the fossil record somehow associated either with humans' transition from hunter-gatherers to pastoralists or the retreat of the ice?
... that will emerge over the next decade ...
Wow. Ten years. A bit long to wait with bated breath, but that's the way I feel about it. Then I never had much patience.
So many dogs that I loved in my mid-century youth simply aren't the same critters anymore, with differences in both structure and temperament. The modern purebred breed is an amazing example of human intervention.
I found this side-by-side photo's to illustrate your point.
And here's a 1950s era boxer. My Rosie was definitely a throwback to this era. Might be hard to see much of a difference, but the neck was longer and the body leaner.
Here's a good summary that includes your boxer:
Sometimes the younger pups are fostered, so they are at least in households with other dogs and possibly litter mates. Other dogs give lots of lessons on manners to young pups.
You can also look for shelters that have programs such as Dogs Playing for Life, which really help with socialization. My local shelter adopted that program and I was very impressed.
Something's puzzling me, though - I don't know if I'm missing something obvious - about these two sentences -
The researchers estimate that dogs and wolves diverged genetically between 36,900 and 41,500 years ago, and that eastern and western dogs split 17,500–23,900 years ago. Because domestication had to have happened between those events, the team puts it somewhere from 20,000 to 40,000 years ago.
Why does it have to have happened between those two events? I'd assumed that dogs diverged from the ancestral wolf either after they'd been domesticated or during the process.
ETA: Also note that the earlier date they give for domestication lies within the range given for speciation so that last sentence about it happening between the two events must be an over-simplification of what they really think.
It makes sense, I suppose - if I'm understanding correctly, they are saying that ancient humans would have selected for dogs that obviously liked them - we all like being liked ...
Also, while not new, on the topic of >83 alaudacorax::
"However, unlike previous research which suggests that, during the process of domestication, dogs were selected for a set of cognitive abilities, particularly an ability to discern gesture and voice, vonHoldt and Shuldiner’s research posits that dogs were instead selected for their tendency to seek human companionship."
Which speaks to the issue of what traits, and by extension what genes, were bred for after protodogs were coexisting with humans.
The social aspect, being able to get social satisfaction from another species, creates its own isolated population. Those of their species who didn't like that niche ("People? Yuck!") self-selected out of the breeding group.