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A Rambling: Semi-Coherent thoughts about recent Dog-Wolf Evolution research, and the effect on Human Perspective, from a Behavioral Standpoint.


Shauna Lee - February 25, 2019 - 0 comments

For a long time, Scientists have researched and theorized on how and when the domesticated dog we know and love today, evolved from the wild and untamed wolf.

Genetic research on their shared ancestry has eliminated all other species but the wolf as their origin. However, they’re still unable to pinpoint the exact time frame or confirm precisely how the process of this transformation unfolded. Despite their nearly identical genetic similarities, they are two separate species with very different behaviors. A more recent DNA analysis of dog-like remains found in 1975 from southern Siberia, point to the assumption that dogs have been a separate species from wolves much longer than was previously accepted. This new data dates their domestication back as far as 33,000 years(Druzhkova and Thalmann, 2013). Another new analysis, of the first human-dog grave ever discovered, was recently made by Veterinarian and Archeologist Luc Janssens. His research depicts a relationship that included a strong emotional bond, and not just one of bilateral convenience(Janssens, 2018), which dates an emotional connection between humans and dogs to have been established at least 14,000 years ago back in the Paleolithic Period. This research, and more, indicate that humans and dogs possibly shared a mutual, and intentional, desire to form, and maintain, a relationship, as they co-evolved. This new hypothesis of “Active Social Domestication” and the thought process of us both, choosing, to become socially and emotionally bonded partners, greatly effects our understanding of this species and their behavior(Portl & Jung, 2018). Previously, dogs were assumed to just be a highly adaptable scavenger that self-domesticated as a survival tactic, eventually, becoming the lovable life partners they are today(Coppinger and Coppinger, 2001). Is it truly possible they have been that this whole time? I think so.

While most mammals have seen a decline in their populations over the years, dogs are one of the only other mammals that has successfully survived as long as humans.

Evolutionary research has been essential to the incredible insight we’ve gained about their health and nutrition, levels of intelligence, and cognitive abilities, although we still have a long way to go in order to fully understand every aspect of their behavior. Especially behavior influenced by emotion. Over the years we’ve learned that human-kind shares a lot of similarities to dogs. As highlighted in the recent publication “Scavenging Hypothesis: Lack of evidence for Dog Domestication on the Waste Dump”, through evidence of similar social and mental functions, and similar activity in the same areas of our brain, we’re able to communicate and understand each other with ease. Like us, dogs use and can understand communication signals via body language. They can recognize emotions by reading facial expressions and can communicate intent to us by display attention attracting behaviors and using directional components like gaze alteration. We are even able to show emotional contagion between our two species(Portl & Jung, 2018). Is it so far-fetched to believe our desire for contact with each other has always had an emotional aspect to it?

If you read the book “How Dogs Love Us” written by Neuroscientist, Dr. Gregory Berns, he states in it that :

“The defining trait of dogs, therefore, is their interspecies social intelligence, an ability to intuit what humans and other animals are thinking.”

The results from Dr. Berns “Dog Project” opened our eyes to how much like us dogs really are, and how emotionally intelligent they can be. Through his fMRI research we found evidence of social learning and social cognition. Dr. Berns learned that they have a “Theory of Mind” (the ability to interpret one’s own and other people’s mental and emotional states, understanding that each person has unique motives, perspectives, etc.) and the same degree of consciousness as a human child. That they’re sensitive to our intentions, and attention, where it’s directed, its context, and understanding when it’s important to respond. They pay attention to what we do in detail, can envision what we’re thinking, and then change their behavior according to those assumptions. This also demonstrates high social intelligence and the ability to empathize. This tells us, that dogs, are in fact, sentient beings. They’re able to think, and reason. They can experience pain, and pleasure, and feel emotions such as joy, sadness, fear, and possibly, even love. By asking the question “Do dogs love us?” Dr. Berns took us down a black hole of research that uncovered that they can, and how. Knowing how incredibly comparable their ability to think and feel is to ours, has caused a considerable shift in the way we interpret their behavior. With a clearer understanding of their motives and intentions, it’s given us the ability to explore the depths of the dog-human relationship and the vigor of our bond. When you compare Dr. Berns research alongside the recent Janssens analysis, mentioned above, where he outlines details of the special care given to the puppy found in the Oberkassel grave, it’s impossible not to assume, that this obviously well cared for puppy, likely returned his caretakers fondness & affection(Janssens, 2018). This puppy and the humans that took care of him, more than 14,000 years ago, shared an emotional attachment much like the one we share with our dogs today.

Assumptions aside, look at the plethora of fascinating scientific evidence documenting the positive psychological and physiological effects of the dog-human relationship.

No other two species share such an extraordinary connection and influence on one another. From a physiological standpoint we have documentation of increased plasma oxytocin, prolactin, phenylacetic acid, and dopamine (Odendaal, 2000; Odendaal and Meintjes, 2003; Handlinetal, 2011), increased salivary immunoglobulin, indicating good immune system functions (Charnetski, 2004), a decrease in cortisol levels (Odendaal, 2000; Odendaal and Meintjes, 2003; Beetz, 2011), lower epinephrine and norepinephrine levels (Cole, 2007), a decrease in heart rate and blood pressure (Friedmann, 1983; Grossberg and Alf, 1985; Jenkins, 1986; Handlin, 2011; Nagengastetal, 1997; Demello, 1999), lower cholesterol levels and generally a reduced cardiovascular risk(Giaquinto and Valentini, 2009; Garrity, 1989; Raina, 1999; Parslow, 2005; Siegel, 1990; Stallones, 1990; Winefield, 2008). From a psychological standpoint we have documentation of significantly reduced feelings of anxiety, fear, depression, and loneliness(Banks and Banks, 2002,2005; Barker, 2003; Cole, 2007; Lang, 2010) and even a reduction in aggressive behavior (Hergovichetal, 2002; Kotrschal and Ortbauer, 2003). Across multiple studies, dog owners have been documented to have better mental and physical health, better fitness levels & exercise more, have fewer sleeping problems, go to fewer doctor visits, and take less days off from work (Headey, 2008; Headey, 1999; Na and Richang, 2003; Headey and Grabka, 2007). When you think of the magnitude of the positive influence that dogs have over our lives, it’s difficult to imagine them ever not being our constant companion. Perhaps that’s why it’s so easy to anthropomorphize them. The more similarities we discover, the more we collectively, and subconsciously, interact with them as we would with human family or friends. It also makes it increasingly difficult to accept them ever being a wild and untamed animal, such as a wolf.

I have my own theory on how dogs evolved and it’s fairly simple.

Wolves and humans, one day, happened to discover the existence of each other. Through their own natural curiosity, they started to seek out more opportunities to observe and study one another. Through this monitoring, we slowly got used to each other’s presence. We likely learned a lot from watching each other, honing skills such as hunting, or defense techniques against shared predators. After some time, we started to understand each other’s routines and recognize each other’s body language. Eventually one single brave human and wolf, felt comfortable enough in each other’s presence, to let down their guard and meet to interact up close and personally. I imagine it was much like the first time any one of us has ever pet a dog. A moment of excitement, a rush, a thrill, afraid and unsure if this unknown beast will hurt you, or if they feel as soft and warm as you had imagined. This is where I think it all began. That first interaction produced some of those physiological effects mentioned above, particularly the hormonal effects, and the first man and wolf shared a magical moment, overcome with euphoria, and relief. Never feeling a rush of emotion in that way, its powerful impression fueled their desire to continue interacting with one another, until they became good friends. Through that first interspecies friendship, the dog-human relationship snowballed. This is also where I think the discoveries made by russian Geneticist, Dmitri Belyaev, during his Silver Fox experiments come into play. Specifically, the chemical changes that lead to the physical changes. A reduction of fear lead to less adrenaline in their system, which lead to an increased tolerance of human presence, which lead to more hormonal changes, which ultimately caused the physical changes. As hypothesized in the “Active Social Domestication” theory, I too, believe that the first wolves and humans not only chose to form a relationship that would stand the test of time, but evolved together, alongside each other(Portl & Jung, 2018).

Regardless of my own theories, or anyone else’s, one thing is certain, research like this is incredibly important for us to clarify because it helps us gain better insight to another species.

Understanding their behavior, and the motivation behind it, leads us to a greater awareness of the incredibly unique bond our two species share. Dogs are human-kinds best friend, our closest ally. Understanding them is essential to understanding ourselves. Comprehending the evolution process and behavioral traits of the only other species to survive as long, and procreate as far and wide as we have, only increases our own chances at a long future of survival. Furthermore, it has significant influence on our whole society. It has economic and environmental impacts, with our conservation and resource management concerns. It impacts our advancement in sciences such as neurobiology, neuroscience, and psychology. It affects the welfare of animals and how they’re cared for, from a biological and medical standpoint. And, because of our vast similarities, it affects our own personal care, by influencing how certain research is conducted, interpreted, and applied across species. Our co-evolution is a crucial piece to the puzzle of our shared history. Just like any relationship you share with another living being, the more you know about each other, the better you understand each other, and the deeper your relationship can grow. Who, that has ever experienced the incredible love and loyalty of a good dog, would ever want anything less than that?

 

 

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