A new hypothesis has been put forward, explaining why breeding for tameness and domestication causes changes not only in dogs’ behavior, but also their looks.
Monthly scientific journal Genetics, usually focusing on investigation of biochemistry, heredity and genetics, has recently published an article¹ on dog breeding for tameness with a hypothesis on a very interesting idea.
Back in the 19th century when industrialization was moving forward, Charles Darwin was educating people on the ancestry of humanity and breathing species in general. One of his many proposed theories was in regard to domesticated mammals who, compared to their ancestors from the wild, were not only a lot more tame, but also differ in their characteristic features such as bigger areas of white fur on the body, floppier ears, as well as smaller jaws and younger looking faces.
For more than 140 years, there was no proof to this theory, but a new Perspectives scientific article suggests that he might have been right all along.
Authors of the study suggest that the connecting link between breeding dogs for tameness and their more juvenile looks could be due to a group of embryonic stem cells by the name of neural crest. This is the first ever unified hypothesis which connects a portion of components of the “domestication syndrome.”
“Because Darwin made his observations just as the science of genetics was beginning, the domestication syndrome is one of the oldest problems in the field. So it was tremendously exciting when we realized that the neural crest hypothesis neatly ties together this hodge-podge of traits,” said one of the paper’s authors from Humboldt University of Berlin, Adam Wilkins, who also works as an editor for Genetics journal.
The article gives a very detailed and scientific explanation to the process, but in short – this is how it works.
Cells of the neural crest are normally formed around the developing spinal cord of early vertebrae embryos. As those embryos will grow and mature, the cells will then move to different parts of the body where they affect and give rise to other tissue types of the mammal. Those affected will usually be ears, parts of the skull and jaw, teeth, pigment cells and “fight-or-flight” adrenal glands. It can also potentially affect your dog’s eye color, coat and your dog shedding cycles.
“This interesting idea based in developmental biology brings us closer to solving a riddle that’s been with us a long time. It provides a unifying hypothesis to test and brings valuable insight into the biology of domestication,” said Editor-in-Chief at Genetics, Mark Johnson.
Indeed it does. Now other scientists are mapping the genes that have been changed due to domestication in other animals, like foxes and rats.
Wilkins has noted that without these animals, humanity might not have thrived the way it did over the last few centuries, and he’s probably right. Domesticated animals had a big impact on the way our society has evolved and it will continue to affect our civilization as we move forward and continue to cherish our pets with responsible care, only holistic dog foods, love and attention.
- A. S. Wilkins, R. W. Wrangham, W. T. Fitch. The “Domestication Syndrome” in Mammals: A Unified Explanation Based on Neural Crest Cell Behavior and Genetics. Genetics, 2014; 197 (3): 795 DOI: 10.1534/genetics.114.165423