Dogs were the first domesticated animal. They were domesticated by humans before the end of the Pleistocene (1). Dogs have been genetically distinguishable from wolves for about 14,000 years. Since then, dogs have been bred for specific purposes and even bred with wolves in some cases. This leads to a huge variety of genetics and behavior. Hunting behaviors of dogs evolved drastically from wolves throughout time. In general, wolves tend to have more hunting abilities, while feral and stray dogs tend to scavenge (2). This change was even more evident as humans evolved to have agricultural lifestyles in Neolithic Europe (1).
Evidence for this change in lifestyle can be seen genetically with the extreme copy number expansion of the amylase gene (AMY2B) in domesticated dogs. This change is an adaptive response to the addition of starches and grains into the dog’s diet, giving genetic proof that dogs have adapted to eat an omnivorous diet (1). Evolution has affected the canine genome as well as the gut microbiota (bacteria populating the canine gut). The gut microbiome of domesticated dogs has evolved so that it is capable of digesting a high carbohydrate diet or a high protein diet (3), allowing dogs to tolerate changes in diet, for example, the change from a kibble based diet to a raw food diet.
- John W. S. Bradshaw, The Evolutionary Basis for the Feeding Behavior of Domestic Dogs (Canis familiaris) and Cats (Felis catus), The Journal of Nutrition, Volume 136, Issue 7, 1 July 2006, Pages 1927Sā1931S, https://doi.org/10.1093/jn/136.7.1927S
- Simone Rampelli, Silvia Turroni, Florencia Debandi, Antton Alberdi, Stephanie L. Schnorr, Courtney A. Hofman, Alberto Taddia, Riccardo Helg, Elena Biagi, Patrizia Brigidi, Federica D’Amico, Maurizio Cattani, Marco Candela, The gut microbiome buffers dietary adaptation in Bronze Age domesticated dogs, iScience, Volume 24, Issue 8, 2021, 102816, ISSN 2589-0042, https://doi.org/10.1016/j.isci.2021.102816. (https://www.sciencedirect.com/science/article/pii/S2589004221007847)
- Alessandri, G., Milani, C., Mancabelli, L., Mangifesta, M., Lugli, G.A., Viappiani, A., Duranti, S., Turroni, F., Ossiprandi, M.C., van Sinderen, D., & Ventura, M. (2019). Metagenomic dissection of the canine gut microbiota: insights into taxonomic, metabolic and nutritional features. Environmental Microbiology, 21, 1331ā1343.