Talk:Origin of the domestic dog
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[edit] Wolf prehistory
Article still requires the prehistory of the wolf, but it is a good starting point SirIsaacBrock 15:22, 14 May 2006 (UTC)
[edit] Title
The title is 'Origin of the domestic dog'
Do we need 'domestic'? If this article is to describe the "Ancestry of the dog", it will apply to all dogs , not just domestic i.e. Dingo and Carolina Dog , infact it would be nice to include a section on feral dogs. GameKeeper 20:38, 14 May 2006 (UTC)
- No this a domestic dog. Dogs that have become feral after domestication is a different subject. Cordially SirIsaacBrock 21:13, 14 May 2006 (UTC)
[edit] Removed material from molecular systematics
[edit] Example: the phylogeny of the domestic dog
For example, Vilà et al (1997) determined haplotypes from a sequence of 261 base pairs in the mitochondrial DNA of 140 domestic dogs, 162 wolves, 5 coyotes, and 10 jackals (of three different species). The dogs were drawn from 67 different pure breeds and 5 cross breeds, and the wolves were drawn from 27 distinct geographically defined populations. The coyotes and jackals were used as the out group.
Vilà et al found 27 distinct haplotypes among the wolves, and 26 among the dogs. The wolf haplotypes differed from each other by no more than 10 bases, and the dog haplotypes differed from each other by no more than 12. The maximum difference between a dog haplotype and a wolf haplotype was 12 substitutions, whereas the minimum difference between a dog haplotype and any coyote or jackal haplotype was 20 substitutions. Vilà et al therefore concluded that their data supported the current classification of the domestic dog as a subspecies of the wolf rather than a domesticated form of some other species of canid.
Vilà et al then proceeded to use cluster analysis to construct dendrograms that grouped the different wolf and dog haplotypes by similarity. There are many different forms of cluster analysis, so they used several of them and showed that they all gave the same results, which were that:
- The correlation between traditional dog breeds and haplotypes was poor: many breeds contained several haplotypes and many haplotypes were found in several breeds.
- The dog haplotypes fell into four distinct clades, one of which included 19 of the 26 dog haplotypes and no wolf haplotype; the highest estimate of the mean divergence within this large clade was 1% (2.6 substitions).
- This major dog clade, and two of the other three dog clades, fell into a single larger clade which also included some wolf haplotypes.
- The haplotypes in the fourth dog clade were more similar to a number of wolf haplotypes than to any other dog haplotype, and the wolf haplotypes in these clades were more similar to the dog haplotypes than to the other wolf haplotypes. The hypothesis that all the dog haplotypes fell into a single clade that did not include any wolf haplotypes was rejected in a significance test.
From their cluster analysis results, Vilà et al concluded that:
- From 1: Traditional dog breeds are genetically diverse (i.e. they have been derived from a range of individuals of different descent)
- From 2: Dogs and wolves have been largely isolated from each other for long enough for genetic coalescence to have occurred in most of the dog population.
- From 3 and 4: Dogs do not derive from a single parentage. Hybridisation between dogs and wolves must have continued after the initial domestication of dogs, introducing new wolf genes into the domestic stock.
From the quantitative data on haplotype similarity, Vilà et al also proposed a new date for the first domestication of the dog. The first archaeological evidence of morphologically modern dog remains found in association with human remains is from 14000 years ago. On the other hand, palaeontological evidence shows that wolves and coyotes were separated about 1 million years ago. Since wolves and coyotes show a minimum 20-base divergence, we can estimate that divergence grows at a rate of about 1 substitution per 50,000 years. If all the dogs whose haplotypes are found in the large clade derive from a single parental line, we would expect that the 2.6-base divergence within that clade would have taken 130,000 years to emerge. Vilà et al therefore propose that the initial domestication of dogs occurred around 130,000 years ago, with some other event about 15,000 years ago leading to morphological change within the domestic dog population.
[edit] Merger Proposal
The "Dog#Dog_breeds" section is actually "Dog#Dog_breeds#Neoteny in the rapid evolution of diverse dog breeds", which doesn't belong under "Dog breeds", but should logically be in any discussion of ancestry. Unfortunately, Wiki cannot address level 3 headings, so I have to stuff around this way. Gordon | Talk, 07:26, 1 January 2007 (UTC)
- Oops. Yes Wiki can. So I didn't have to stuff around, and now I have to fix it. But it's not a serial address scheme, which it should be. Gordon | Talk, 07:47, 1 January 2007 (UTC)
[edit] Support
- I agree with the merge. Perhaps with the merger the article title should be changed from "Origin of the Domestic Dog" to "Evolution of the Domestic Dog." Geohevy 01:27, 12 February 2007 (UTC)...
- I support the merge. Discussion of neoteny after a discussion of Dmitry Belyaev's experiment is appropriate. The changes to physical traits mentioned: "spotted or black-and-white coats, floppy ears, tails that curl over their backs", are generally considered products of neoteny in mammal species. However: I would oppose a change in title as the article discusses both social and biological developments during domestication. Kulervo 21:37, 4 March 2007 (UTC)
[edit] Oppose
i think that it is easier to find the information if it is in multipul places.
