biodiverseed:Ancient dog breedsFourteen ancient breeds of dog have been identified through advances
biodiverseed:Ancient dog breedsFourteen ancient breeds of dog have been identified through advances in DNA analysis. These breeds of domesticated dog show the fewest genetic differences from wolves.At the time that dogs diverged from the wolf, humans were nomadic hunter-gatherers who had not yet domesticated any other animal, as humans did not remain in one place for long enough to raise or keep animals. Humans still indirectly spurred the speciation event that caused wolves to eventually become the dog. Genetic analysis shows that one of the primary mechanisms underlying the speciation began with mutations that randomly occurred in wolf genes AMY2B, MGAM and SGLT1 for independent populations of wolves. The mutations increased the expression of these gene loci by nearly 7.4 fold, which conferred the ability to much more effectively digest and utilize nutrients from starches and fats.The implications of these mutations can be seen in archeological records that show that dog ancestors began to follow groups of nomadic humans and eat the more starchy and fatty leftovers of the foods humans ate. This caused changes in the morphology of the wolf snout and teeth which became shorter and more adapted to eating a variety of different foods rather than the original function of hunting and taking down large prey. The morphology of the wolf brain also changed in the areas of the limbic system having to do with fight or flight responses. These areas began to shrink by 20-40%; enabling wolves to be less afraid of humans and more willing to live and interact in close proximity to them.On an ontogenetic developmental level, these wolves eventually evolved much higher social-cognitive skills with humans; they were able to incorporate humans into their social hierarchal system as the new “alpha” or dominant member of society. This led to a much greater degree of obedience, and the ability to process emotional signals from humans, including an understanding of subtle communicative cues such as the importance of what a human is looking at. [Read more]Graphic: “Doggies’ desert development decoded.” in Nature#domestication #evolution #anthropology -- source link