Learning and Domestication
Biology 342 | Fall 2014
How Interaction with Humans has Altered Animal Behavior
Methods of Fox Domestication
Dmitri Belyaev began the project of breeding silver foxes at a fox farm for tameness. He selected more friendly animals based on a behavioral score of interaction with humans, and bred these to create a domesticated line he called "elite" foxes. These foxes displayed multitude of physical changes that paired with the behavioral traits of tameness that they selected for.
Resulting Morphological Changes
Domesticated foxes showed piebald coloration, a change in pigmentation of white and black patches that has been seen in other domesticated animals. The emergence of piebald pigmentation is linked to changes in neuro-endocrine physiology . The melanocyte-stimulating hormone has receptors that not only regulate pigmentation but also in the hippocampus and hypothalamus, which are the structures regulating exploratory and emotional behavior .
Comparisons of foxes bred for tameness and foxes not bred for tameness with regards to exploratory activity and cortisol levels (as an indicator of stress). From Lyudmilla Trut and Dmitri Belyaev's study of foxes .
According to Lyudmilla Trut, "morphological changes started to arise in foxes that had been subjected to selection for tameness for 8-10 generations. Many changes in characters were concordant with those not only of dogs, but also of other domestic animals" .
Dogs show a different expression of neuropeptides CALCB and NPY in the hypothalamus (associated with emotion) than wild canids . The hypothalamus is involved in exploratory behavior, specific emotional, endocrinological and autonomic responses. This may be responsible for the differences in sociability we observe between dogs and wild canids.