In this blog, I will discuss the domestication of dogs and how we as behavior professionals can use this knowledge in our work with dogs and their caretakers. Throughout this, several relevant topics will be discussed, including a variety of factors impacting domestication, the changes that the process had on dogs, including their diet, as well as the impacts and differences it had on modern-day dog breeds. Furthermore, the way domesticated dogs are often viewed today, including in the media, and the potential ramifications that we behavior professionals have to take into consideration will be covered. Additionally, the scavenging behavior of dogs will be discussed, and how this can lead to undesirable behaviors in human homes, as well as the potential benefits that this type of behavior can have when appropriate outlets are provided.
There is much debate about when, where, and how dogs were domesticated by humans.
Various types of research have been looking into the subject over the years, but, what even is “domestication?” Domestication involves the keeping of animals under human control, which over several generations results in animals that are genetically different to their ancestors (Case, 2023, p. 42; Miklósi, 2015, p. 324 ), and where a human-dog relationship is formed (Vonholdt & Driscoll, 2017, p. 25). Dogs, much like their wolf ancestor (Canis lupus), are part of the family Canidae (Vonholdt & Driscoll, 2017, p. 23), and the dog’s ancestors are most likely to have originated from East Asia and/or Europe/Near East (Miklósi, 2015, p. 360). Dogs have likely co-evolved with humans for 32,000 years or more (Ha & Campion, 2018, p. 17). Interestingly, no evidence exists of dogs being purposefully domesticated by humans (Lord et al., 2017, p. 54), which considering the purposes that future dog breeds have been, and still are, used for, is remarkable.
Today, millions of free-ranging dogs around the world still live primarily as scavengers (Coppinger & Feinstein, 2015, p. 9; Case, 2023, p. 72). As human agriculture began developing 10,000-15,000 years ago (Miklósi, 2015, p. 332), and with wolves being opportunistic scavengers in addition to predators, these new settlements may have provided a reliable supply of surplus food (Case, 2023, p. 51). This may have played a key role in the domestication of dogs, as their ancestors had a reason to be in close proximity to humans. Such a new way of life as scavengers around humans, would, through natural selection, begin to favor individuals who were overall smaller in size, as they would have been able to more easily survive on little food (Case, 2023, p. 53; Clutton-Brock, 2017, p. 11). In addition to the reduced overall size of the dogs, their teeth also gradually became smaller (Clutton-Brock, 2017, p. 11), and other features changed as well. The smaller size also made them more efficient at scavenging (Coppinger & Coppinger, 2002, p. 61), thus enhancing their chances of survival. Other morphological changes include not just the size or the variability of size between breeds, but also elements like tail shape, coat type, as well as floppy ears in many dog breeds, which wolves do not have (Ha & Campion, 2018, p. 179).
Changes also occurred to the female dog’s reproductive cycle, as well as to the male dog’s sexual capabilities. Unlike wolves who have one annual estrous cycle, except for a few breeds, dogs have two estrus cycles each year (Miklósi, 2015, p. 382). Male dogs reach sexual maturity much sooner than wolves (e.g. 6-9 months compared to two years of age) and are fertile throughout the year, unlike male wolves who are seasonal like their female counterparts (Case, 2023, p. 55). This is especially important information in multi-dog households where there may be several intact females or an intact female and several intact males, where not only unwanted pregnancies can occur, but also potential intra-sex and/or intersex aggression during estrous.
We see the effects of evolution and domestication in our modern-day dog breeds as well, as humans have artificially selected for certain traits in our canine companions to perform a variety of working tasks. As humans began to keep livestock, having dogs protect them and move them was greatly beneficial to us (Brophey, 2018, p. 215). Today, we see examples of these like the livestock guardian breeds such as the Anatolian Shepherd and herding dogs such as the Border Collie (Brophey, 2018, pp. 115, 213). While there is more to each breed of dog than their genetic makeup, including their early socialization and habituation to the environment, keeping the roles these dogs were originally bred to perform in mind is beneficial. For example, the “eye” part of the predatory motor pattern seems to be intrinsically reinforcing for Border Collies, and sometimes removal of the stimulus is the only way to stop/prevent the behavior (Lord et al., 2017, p. 52).
On the other hand, a dog like the Anatolian Shepherd may be more prone to barking related to territorial behavior as part of their genetic makeup (Brophey, 2018, p. 116). While this may not necessarily be the case with the dog in front of us, knowing that there’s a potential for this behavioral occurrence due to genetics can help our clients understand “why” their dog may behave this way. As we can see, many changes appeared as humans and dogs evolved, and their lifestyles shifted to a more agricultural-based way of living.
As previously mentioned, human agriculture began approximately 10,000-15,000 years ago, and while that lifestyle change likely played an important role in the domestication of dogs, it may have also had an impact on their digestive system. Other changes that started to occur were related to the canine diet, especially their ability to move from a carnivorous diet to a more omnivorous one (Rampelli, 2021, p. 6). One area of the canine digestive system that has undergone significant change is their ability to process starch. This is thanks to the gene known as α-amylase 2B (AMY2B) (Reiter et al. 2016, p.1) of which much higher numbers are found in dogs compared to wolves (Axelsson et al., 2013, p.362). Significant variation in copy number can also be found among dogs who are from places where prehistoric agriculture was present compared to dogs from places without prehistoric agriculture (Arendt et al., 2016, p. 303). This would indicate the development of an adaptive function of increased starch digestion during domestication, as dogs were scavenging near human settlements.
The domestication of dogs has changed many elements of what a dog is today, including its morphology, digestive system, and reproductive system. Their ability to perform various roles, including guarding and herding livestock through artificial selection, has also had an impact on humans’ ability to keep valuable food sources safe from potential predators and made it easier to move livestock from one place to another. There is no doubt that dogs and humans have developed a strong bond and understanding over the course of thousands of years, further highlighted by dogs’ ability to learn human words and gestures (Ha & Campion, 2018, p. 180). However, many different challenges do exist in the dog-human relationship, and here, great variation between those challenges also exists. Additionally, how best to deal with these challenges also divides opinions among dog professionals as well as dog caretakers.
The term “man’s best friend” is one that dog behavior professionals, myself included, will come across from time to time, and one that can often be found in the media when describing modern dogs (Coppinger & Feinstein, 2015, p. 8). However, this term may not always be appropriate when much of the work we do as professionals revolves around modifying undesirable behaviors (Coppinger & Feinstein, 2015, p. 9), as well as coming up with management strategies to keep people safe, and also ensuring our safety during a behavior consultation (O’Heare, 2017, p. 60). Knowledge of dog domestication can benefit the overall understanding of the dogs in front of us, and our approach to working with them. Dogs do have 42 permanent teeth, after all, like most carnivores do (Case, 2023, p. 129; Ha & Campion, 2018, p. 11). While these can vary in size depending on the type of dog, they do exist and can cause injuries if we don’t respect their communication signals or resort to varying types of aversive methods.
A thing that is becoming ever more prevalent is wanting dogs to behave appropriately in all situations, and natural behaviors like vocalizing or digging are no longer welcome (Bender & Strong, 2019, pp. 138-139). Many common undesirable behaviors, including counter-surfing and eating food off the ground on walks, can be traced back to natural dog behavior (Case, 2023, pp. 612-613). While these behaviors can be extremely frustrating for the human, and potentially dangerous for the dog if they ingest something toxic, helping people understand where these behaviors originate from can be helpful.
If we look at the example of dogs scavenging on walks or counters, we can clearly see the impacts of domestication. Dogs choosing to scavenge food near human settlements rather than hunting game in larger groups was one way of surviving (Brophey, 2018, p. 74), and it likely would not have upset the humans around them. It could, perhaps, even have benefited humans if the dogs managed to keep potential predators away. This is a great example of a previously largely unimportant behavior to humans, which is now deemed problematic in a variety of circumstances.
Remember the aforementioned self-reinforcing behavior of “eye” in the Border Collie, and how the removal of the stimulus is sometimes the only way to stop/prevent it? Sometimes this behavior can transpire onto stimuli that we don’t want, like “giving eye” and then stalking/chasing children (Brophey, 2018, p. 214).
Caretakers do not want to have to rush their dog to an emergency veterinarian because their dog ate something toxic. People generally do not want to have a young child be traumatized because they got “stalked” around the living room when adult humans were not supervising. However, what if we could use this knowledge of domestic dogs, and certain breed-specific behaviors to educate dogs and their human caretakers, as well as provide outlets for natural behavior?
If we take our dumpster-scavenging canine companion, manage the food on the ground or the counter as best as possible, and instead provide foraging opportunities that mentally challenge them (Bender & Strong, 2019, p. 219), then perhaps we can provide appropriate outlets for our dogs. And similarly, we can use nose work to mentally stimulate our dogs, or dog sports like Treibball for our Border Collies and other herding breeds to allow them a safe outlet (Bender & Strong, 2019, pp. 217-219). As such, feeding all of our dogs’ daily calories in a food bowl may be counterproductive. While I do not believe in a “nothing in life is free approach” as this can have detrimental impacts on the dog (O’Heare, 2017, p. 361), a mixture of set meals and opportunities for scavenging, sniffing, and foraging via snuffle mats, toilet paper rolls, and treat searches (Bender & Strong, 2019, pp. 156-167) among others, we may be able to better meet our dogs’ needs, and some that likely played a big role in their domestication. This may also impact our relationships with our canine companions positively, as certain innate behaviors will be less likely to manifest themselves in undesirable ways.
In summary, the domestication and evolution of dogs from their wolf ancestor have many layers and factors to consider. While the exact locations, timing, and reasons behind this process are still being debated, dogs have undergone several changes including morphological, behavioral, reproductive, and digestive. The scavenging behavior around newly developed human agriculture likely played an important role in domestication and probably aided their ability to more efficiently digest starch. As people began selecting for certain traits to aid them in a variety of working tasks, dogs underwent further changes. Many of these can be seen today, and some can become problematic in human homes when appropriate outlets are not provided. Having a solid understanding of domesticated dogs can help behavior professionals better guide people on the reasons behind dog behaviors, as well as provide guidance on suitable outlets.
References:
Arendt, M., Cairns, K., Ballard, J. et al. Diet adaptation in dog reflects spread of prehistoric agriculture. Heredity 117, 301–306 (2016). https://doi.org/10.1038/hdy.2016.48
Axelsson, Erik & Ratnakumar, Abhirami & Arendt, Maja-Louise & Maqbool, Khurram & Webster, Matthew & Perloski, Michele & Liberg, Olof & Arnemo, Jon & Hedhammar, Ake & Lindblad-Toh, Kerstin. (2013). The genomic signature of dog domestication reveals adaptation to a starch-rich diet. Nature. 495. 10.1038/nature11837.
Bender, A. and Strong, E. (2019). Canine Enrichment for the Real World : Making It a Part of Your dog’s Daily Life. Wenatchee, Washington: Dogwise Publishing.
Brophey, K. (2018). Meet Your Dog: the Game-Changing Guide to Understanding Your Dog’s Behavior. Chronicle Books, USA.
Case, L.P. (2023). The Dog: Its Behavior, Nutrition, and Health. 3rd ed. Arnes, AI: Wiley.
Clutton-Brock, J. (2017). Origins of the dog: the Archaeological Evidence. In: J. Serpell, ed., The Domestic Dog Its Evolution, Behavior and Interactions with People. 2nd Ed. Cambridge, United Kingdom: Cambridge University Press, pp.7–21
Coppinger, R. and Coppinger, L. (2002). Dogs: a New Understanding of Canine origin, behavior, and Evolution. Chicago: University of Chicago Press.
Coppinger, R. and Feinstein, M. (2015). How Dogs Work. Chicago: The University of Chicago Press, USA.
Ha, J. C. & Campion, T. L. (2018). Dog Behavior: Modern Science and Our Canine Companions.
Academic Press.
Lord, K., Schneider, R.A. and Coppinger, R. (2017). Evolution of Working Dogs. In: J. Serpell, ed., The Domestic Dog Its Evolution, Behavior and Interactions with People. 2nd Ed. Cambridge, United Kingdom: Cambridge University Press, pp.42–66.
Miklósi, A. (2015). Dog Behavior, Evolution and Cognition. 2nd ed. Oxford University Press, United Kingdom.
O’Heare, J. (2017). Aggressive Behavior in Dogs. 3rd Ed. Behave Tech Publishing, Canada.
Rampelli S, Turroni S, Debandi F, Alberdi A, Schnorr SL, Hofman CA, Taddia A, Helg R, Biagi E, Brigidi P, D’Amico F, Cattani M, Candela M. The gut microbiome buffers dietary adaptation in Bronze Age domesticated dogs. iScience. 2021 Jul 9;24(8):102816. doi: 10.1016/j.isci.2021.102816. PMID: 34377966; PMCID: PMC8327155.
Reiter T, Jagoda E, Capellini TD (2016) Dietary Variation and Evolution of Gene Copy Number among Dog Breeds. PLoS ONE 11(2): e0148899. doi:10.1371/journal.pone.0148899
Vonholdt, B.M. and Driscoll, C.A. (2017). Origins of the dog: Genetic insights into dog domestication. In: J. Serpell, ed., The Domestic Dog Its Evolution, Behavior and Interactions with People. Cambridge, United Kingdom: Cambridge University Press, pp.22–41.