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Not long ago I caught a documentary on BBC about our friend Charles Darwin and his famous theory The Origin of Species.
What is now regarded as obvious at the time gave rise much controversy and disbelief.
But now reflecting on the origin of species, I wonder ... "and our canine friends, how is the tree of evolution?
Ok, doing a little web research and photo summary, I found the following theory of evolution:
Mammals evolution tree:
1) The directly ancestral to all later canids is Hesperocyon
(about 40 to 35 million years ago)
2)Immediately follows the Leptocyon, considered a cousin.
(about 40 to 35 million years ago)
3) Descending immediate from Leptocyon comes Eucyon
(about 6 million years ago)
It is believed that the first dogs are descendants of Eucyon therefore deserves a comparison with the wolf.
4) One of the first wolves is believed to have lived and competed directly with the large cave lions and saber tooth tigers, and it is called Dire Wolf
(about 2 to 10 million years ago)
5) The oldest dog skull discovered to date is from Goyet Cave, Belgium with 31,700 years old.
They are clearly different from wolves and is thought to be a transition from wolf to dog.
In the end, only a theory of evolution from the wolf (Canis lupus) to the dog (Canis lupus familiaris) can be imagined.
Multiple and Ancient Origins of the Domestic Dog
Mitochondrial DNA control region sequences were analyzed from 162 wolves at 27 localities worldwide and from 140 domestic dogs representing 67 breeds. Sequences from both dogs and wolves showed considerable diversity and supported the hypothesis that wolves were the ancestors of dogs. Most dog sequences belonged to a divergent monophyletic clade sharing no sequences with wolves. The sequence divergence within this clade suggested that dogs originated more than 100,000 years before the present. Associations of dog haplotypes with other wolf lineages indicated episodes of admixture between wolves and dogs. Repeated genetic exchange between dog and wolf populations may have been an important source of variation for artificial selection.
ref: http://www.sciencemag.org/content/276/5319/1687.abstract?maxtoshow=&HITS=10&hits=10&RESULTFORMAT=&fulltext=vila&searchid=1&FIRSTINDEX=0&resourcetype=HWCIT
Canid phylogeny tree
Other articles:
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