Quite a while I wrote a couple of posts about the domestication of dogs including one about archaeological evidence and the origins of this domestication. Recently I came across an article that completed a DNA analysis of ancient dogs of the Americas (Witt et al. 2015). This study investigated the genomes of canine remains from three sites, in addition to a number of other sites from previous studies.
From the study it was found that the most frequent haplotype was idential to those found in an ancient Siberian dog, making it a likely founding haplotype. Humans were first thought to cross to the Americas around 15 – 20 kya, with subsequent movements before the Bering Strait submerged about 10 – 11 kya. When these individuals came across to the Americas they also brought along their domesicated dogs, with the oldest remains dating to 10 kya BP (Witt et al. 2015). It is then thought that there was possibly admixture (breeding) between domesticated dogs and North American wolves due to shared or similar mitochondrial haplotypes. However, this could have also been a result of a seperate domestication events and Witt et al recommend that additional regions of the genome should be examined to establish the evolutionary history of these dogs.
Invesitgating the evolutionary history of the domesticated dog is not only interesting for the evolution of a species, but also because it may be used as a complemetory data source of human activity. The oldest canine remains suggest that the domestication of dogs could have started around 33,000 years ago. Due to a long period of domestication, along with different goups of people, some breeds of dog have different genes enabling them to survive depending on their environment. For example, wolves have only two copies of the genes that enable the ability to digest starch. However, it has been found that a correlation exisits between dog breeds that originate from a region of human agriculture posessing more copies of this gene then those dogs who were raised in an evniroment with no history of agriculture. The example provided by Witt et al (2015) states that the saluki, which derives from the Fertile Cresent, has 30 copies of the gene whilst the Siberian husky has only two genes (Freedman et al 2014).
Therefore collecting data on the domestication and genetics of canines can provide researchers with a complementary data source to study human population history.
Freedman, A. H. et al. Genome sequencing highlights the dynamic early history of dogs. PLoS genetics 10, e1004016 (2014).
Witt, K. E. et al. (2015) DNA analysis of ancient dogs of the Americas: Identifying possible founding haplotypes and reconstructing population histories. Journal of Human Evolution 79, 105-118,