by Mercy Rhodes
Charlie and my first meeting. Image from Mercy R.
One of my first memories was visiting an animal shelter. My family loves animals and we often went to the local animal shelter to spend time with dogs and cats there. I remember going one day when I was about four and seeing a little puppy in a cage looking up at us with huge eyes. He was brown and white and had thick fur, with the softest ears. It was love at first sight for me and luckily, the rest of my family and the puppy felt the same. Unfortunately, after playing with the puppy at the shelter for a while, we had to go home. My younger sister and I cried leaving him. Imagine our surprise when a few weeks later, on Christmas morning, that puppy was one of our presents. We were ecstatic. We named him Charleston after the town we lived in, Charlie for short. Charlie was one of the best things that could have ever happened to our little family. I remember sneaking him huge bowls of milk those first couple days before my parents caught me because even when I was so young, I wanted to take care of him the best way I knew how. Charlie loved us and was always cuddling and wanting to be pet. We grew up together and I cherished every second. I never stopped sneaking him food. He was especially fond of pizza crust. Sadly, Charlie passed away a couple years ago. He was old and it was his time to go, but it did not make it any less heart wrenching. My family and I grieved for him the same way we have grieved human family members that have passed. That is because he is a family member to us. And yet, he was not human. How did dogs become man’s best friend?
The bond between humans and dogs is one of the most profound and enduring relationships in the history of human civilization. Often referred to as “man’s best friend,” dogs have been a part of human lives for thousands of years, evolving from wild wolves into the diverse and extremely affectionate companions that we know today. The history of this relationship is remarkable. Imagine a world where wolves roamed the forests and humans huddled around fires, sharing their lives beneath the stars. In this ancient scene, a beautiful transformation began, a journey that would create one of the most powerful bonds in history. Diving into the past reveals a captivating exploration into the science of how dogs became man’s best friend and the profound reasons why the relationship is so unique and successful.
The story of how dogs became human companions begins with early interactions between prehistoric humans and wolves. Around 20,000 to 40,000 years ago, during the late Paleolithic era, humans and wolves were co-habitants of the same environments. According to Amanda Pendleton and others in a study called, Comparison of Village Dog and Wolf Genomes Highlights the Role of the Neural Crest in Dog Domestication, these interactions were initially marked by mutual benefits rather than the deep bond we recognize today. Wolves were apex predators and possessed the ability to assist early humans by scavenging. They likely helped human hunting parties by feeding on the remains of their kills, which provided the wolves with a relatively consistent food source. In return, wolves may have offered early humans some advantages, such as warning off other approaching predators or competitors due to their heightened senses. The relationship between the early humans and wolves was pragmatic. Humans provided wolves with food, while wolves helped keep humans safe from other predators. Over time, this symbiotic relationship began to grow and evolve.
The transition from wolves to domesticated dogs is a testament to the power of natural selection and human influence. Paige McAllister concludes in her article, How Gray Wolves Evolved Into Man’s Best Friend, that the evolutionary process involved both selective pressures exerted by humans and genetic changes in the wolves that were more amenable to domestication (2024). Wolves are highly adaptable creatures with complex social structures and a wide range of behaviors. Those wolves that were more docile and less aggressive were likely the first to establish close contact with human groups. These wolves gradually became more accustomed to human presence, and over generations, they exhibited traits that made them more suitable as companions.
Genetic evidence suggests that the domestication process involved a gradual and complex interaction between wolves and humans (Pendleton et al, 2018). Ancient canine remains have shown that domesticated dogs appeared in various regions independently, suggesting that the process was not uniform. Genetic adaptations in these early dogs included changes in size, coat color, and temperament, making them more suitable as companions and helpers. One key factor in this evolutionary process was the selection of traits that favored tameness (Pendleton et al, 2018). Unlike their wild ancestors, domesticated dogs exhibited a range of physical and behavioral traits that facilitated close relationships with humans, such as reduced aggression, increased sociability, and a willingness to follow human commands. These changes were driven by both natural selection and intentional breeding by humans.
The OXTR gene, which encodes the oxytocin receptor, plays a significant role in the bond between humans and dogs. Oxytocin, often referred to as the “love hormone,” is associated with social bonding, trust, and affectionate behaviors in both humans and animals. The presence and functioning of the OXTR gene are crucial in understanding how dogs have developed such a strong attachment to humans. Research, especially Anna Kis’s work in Oxytocin Receptor Gene Polymorphisms Are Associated with Human Directed Social Behavior in Dogs (Canis familiaris), has shown that the oxytocin system in dogs is highly responsive to human interaction. When dogs engage in positive social interactions with humans, such as being petted or playing, their oxytocin levels increase, which in turn strengthens the bond between them and their human companions. Similarly, humans experience an increase in oxytocin when interacting with dogs, reinforcing mutual affection and attachment. Studies have also indicated that the OXTR gene plays a role in the varying degrees of attachment and social behavior observed in different dog breeds (Kis et al, 2014). Some breeds exhibit higher levels of oxytocin receptor activity, which may explain why they are particularly responsive to human emotions and commands. This genetic predisposition contributes to the wide range of behaviors and temperaments observed in domesticated dogs, from highly trainable and affectionate companions to more independent or reserved breeds.
The psychological dynamics of the human and dog relationship are deeply rooted in both evolutionary and social contexts. From a psychological perspective, the bond between humans and dogs can be understood through several key concepts, including attachment theory, social bonding, and emotional support. These bonds are characterized by behaviors such as seeking proximity, showing affection, and displaying signs of distress when separated. Dogs have evolved to be highly attuned to human emotional cues. According to Sarah Marshall-Pescini and others in the study, The Role of Oxytocin in the Dog-Owner Relationship, they are capable of reading human facial expressions and responding to emotional signals, which strengthens their role as companions and emotional support animals (2019). This heightened sensitivity to human emotions is a result of both genetic adaptations and the long history of co-evolution between humans and dogs. The role of dogs as emotional support animals is well-documented. Many people find that the presence of a dog provides comfort and reduces stress, anxiety, and feelings of loneliness. The unconditional love and loyalty exhibited by dogs create a safe and supportive environment for their human companions. This emotional support is particularly significant for individuals facing mental health challenges, as dogs can offer companionship and stability. Furthermore, the social bonding between humans and dogs is facilitated by the release of neurochemicals such as oxytocin and dopamine. The positive interactions between dogs and humans trigger the release of these chemicals, which promote feelings of happiness and well-being. This biochemical feedback loop reinforces the bond between humans and dogs, making it a mutually beneficial and deeply satisfying relationship.
Dogs enrich people’s lives in profound and varied ways, providing meaning that transcends simple companionship. Their impact is particularly evident in emotional support, social connection, and overall well-being. I grew up with Charlie and I counted on his presence and support as I would any friend. Yes, we fed and housed him, but he genuinely wanted to be around us as much as we loved spending time with him. We came to count on and comfort each other if it was ever needed. It was such a blessing to have one of these special kinds of relationships for my own.
The journey of how dogs became man’s best friend is a fascinating story of evolution, genetics, and psychology. From their early interactions with humans as scavengers and helpers to their transformation into loyal and affectionate companions, dogs have undergone a remarkable evolutionary process. The role of the OXTR gene highlights the biological basis for the strong emotional bond between humans and dogs, while psychological theories underscore the profound impact of this relationship on both species. The history of the human-dog bond is a testament to the power of mutual benefit, adaptation, and affection. As we continue to explore and understand this unique relationship, it becomes clear that the bond between humans and dogs is not just a product of history but a living testament to the enduring nature of companionship and trust. Dogs have earned their place as man’s best friend through millennia of evolution and shared experiences, and this bond continues to enrich the lives of countless individuals around the world. The human bond with dogs is not just about cuteness and companionship, it is a profound connection entrenched in biology and shared experiences that should be celebrated.
References
Kis, A., Bence, M., Lakatos, G., Pergel, E., Turcsan, B., Pluijmakers, J., Vas, J., Elek, Z., Bruder, I., Foldi, L., Sasvari-Szekely, M., Miklosi, A., Ronai, Z., & Kubinyi, E. (2014). Oxytocin Receptor Gene Polymorphisms Are Associated with Human Directed Social Behavior in Dogs (Canis familiaris). PloS One, 9(1).
Marshall-Pescini, S., Schaebs, F. S., Gaugg, A., Meinert, A., Deschner, T., & Range, F. (2019, October 12). The role of oxytocin in the dog-owner relationship. Animals : an open access journal from MDPI. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6826447/
McAllister, P. (2024, April 19). How Gray Wolves Evolved Into Man’s Best Friend. VailDaily.com. https://www.vaildaily.com/news/how-gray-wolves-evolved-into-mans-best-friend/
Pendleton, A. L., Shen, F., Taravella, A. M., Emery, S., Veeramah, K. R., Boyko, A. R., & Kidd, J. M. (2018, June 28). Comparison of Village Dog and Wolf Genomes Highlights the Role of the Neural Crest in Dog Domestication. BioMed Central. https://bmcbiol.biomedcentral.com/articles/10.1186/s12915-018-0535-2
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