Canis lupus familiaris

by prescotthbreeden

Ray and Lorna Coppinger said it most succinctly:

“Behavior is the functional component of evolutionary change.  How well an animal runs is the selective force, not its legs.  Paleontologists study the evolution of hard parts because those are what fossilize.  Studying changes in femur lengths, however, leads to the misconception that it is legs that evolved, rather than running or jumping.  For biologists, the evolution of dog behavior is found in the mechanisms of evolutionary change from the antecedent wolf behavior.”  (Coppinger & Coppinger, 1996)

The biggest pitfall when viewing dog behavior from an evolutionary perspective is when people confuse the words of authors like Ray and Lorna Coppinger and claim that ‘because the dog is a descendant of the wolf, giving our dogs a wolf way of life is what they understand best’.  The first problem is that behavior is phenomenally more complex than simply the order in which genes make proteins.  The subject of behavioral genetics in lay discussion often conceptualizes genetics holding its animal host hostage by allelic gunpoint to bend to its will.  It did not help that for a while, science was still trying to understand the question of ‘nature vs nurture’ and everyone had an interpretation.  We know today that it is neither and it is both–the development of an organism comes down to the interaction of genetic activity, neural activity, behavior and environment (Gottlieb, 1991).

"A simplified scheme of the developmental systems view showing a hierarchy of four mutually interacting components in which there are "top-down" as well as "bottom-up" bidirectional influences." (from Gottlieb, 1991)

“A simplified scheme of the developmental systems view showing a hierarchy of four mutually interacting components in which there are “top-down” as well as “bottom-up” bidirectional influences.” (from Gottlieb, 1991)

The second problem is that the wolves we observe today are not the wolves that our dogs evolved from–they too are also evolutionary decedents.  While many well-respected authors have proposed that domestication occurred somewhere from 30,000 to 135,000 years ago (Vila et al., 1997), other well-respected authors argue instead it was likely somewhere between 8,000 to 10,000 years ago, and the matter is hardly settled (Larson et al., 2012).  Regardless of the exact date, since the domestication of the dog, humans have reduced the estimated worldwide wolf population from over 2 million to less than 200,000.  Not only do the wolves today make up a slim 10% of the population that our dogs evolved from, but our dogs have grown into a worldwide estimated population of 500 million—undergoing genetic selection with each generation.  When given the immense differences in ecological requirements, it would almost defy the theory of evolution–the most empirically supported theory in existence (Coyne, 2009)–if there were no variations.  The tendency to make grand generalizations about the behavior of dogs and wolves is extremely problematic at best and a tremendous amount of care should be taken whenever one does.  Discussing animal behavior from an evolutionary perspective is therefore not akin to saying these two sub-species of Canis lupus–grey wolves (Canis lupus lupus) and dogs (Canis lupus familiaris)–are evolutionary reflections of each other.  Animals evolve to adapt to their ecological niche, and for the dog, that niche is our farms, our cities, our streets, our garbage dumps, and most importantly our homes.

References:
Coppinger, R., & Coppinger, L.  Biological Bases of Behavior of Domestic Dog Breeds. 1996, V. L. Voith and P. L. Borchelt, Eds., Readings in Companion Animal Behavior, Veterinary Learning Systems, Trenton, NJ. pp 9-18.

Coyne, J. A. (2009). Why Evolution is True. Penguin.

Gottlieb, G. (1991). Experiential canalization of behavioral development: Theory. Developmental Psychology, 27(1), 4–13. doi:10.1037/0012-1649.27.1.4

Larson, G., Karlsson, E. K., Perri, A., Webster, M. T., Ho, S. Y. W., Peters, J., … Lindblad-Toh, K. (2012). Rethinking dog domestication by integrating genetics, archeology, and biogeography. Proceedings of the National Academy of Sciences, 109(23), 8878–8883. doi:10.1073/pnas.1203005109

Vilà, C., Savolainen, P., Maldonado, J. E., Amorim, I. R., Rice, J. E., Honeycutt, R. L., … Wayne, R. K. (1997). Multiple and Ancient Origins of the Domestic Dog. Science, 276(5319), 1687–1689. doi:10.1126/science.276.5319.1687