Blog Post One - The Human-Animal Bond: Made for One Another

Since the dawn of time, humans and non-human animals have shared the earth with one another. However, we did not always have the same relationship with animals that we have today. All animals were once wild animals to us, and the only interactions we had with them involved hunting or being hunted. It took us thousands of years to domesticate animals to use for food and companionship, and many factors to determine which animals were able to be successfully domesticated.

There is a bond that emotionally connects us to our companion animals known as the human-animal bond, or HAB for short. As was discussed in Meg Daley’s TED talk, the HAB is heavily influenced by oxytocin. Oxytocin is known as the bonding hormone, and is largely responsible for connections between mother and infant. It also plays a role in most other relationships. Oxytocin is present in high levels in social species, and it lowers adrenaline levels so that members of the same or different social species will not be in constant fear of one another. Because of this, primitive humans were able to have some level of interaction with other social species such as lions or wolves. The domesticated dogs that we have in our homes today exist because humans were able to interact with less aggressive wolves closely enough to eventually come into possession of wolf pups by one method or another. When these wolf pups were hungry, human women fed them the only way they knew how; suckling them. This caused oxytocin release in both the human women and the wolf pups, most likely leading to the earliest HABs. Humans eventually bred many generations of the tamest wolves to create the many species of domesticated dog that we have today. As was discussed in lecture, oxytocin is released in both human and dog when a dog is pet and it is also release in both parties when looking into one another’s eyes. Oxytocin release causes a feel-good reaction that rewards both the dog and the human for these interactions. The HAB is stronger than ever today between owners and pets because of the same hormone that first assisted us in the domestication of wolves.

Belyaev with a fox. Examples of domesticated coat color, upper left.

One quality that humans seem to select very highly for in domesticated companion animals is cuteness. We like companion animals that have qualities that we see as infantile, and we like them to retain many of the characteristics that they have as juveniles. The retention of juvenile physical and behavioral characteristics into adulthood is known as neotany, and much of the breeding that we do with companion animals selects highly for this trait. We enjoy pets that stay playful their whole lives with traits like large eyes, and soft, rounded features. These characteristics trigger a protective and nurturing response in humans because they remind us of our own infants. They also activate a key reward center in the brain, the nucleus accumbens. We are hardwired to enjoy traits like these because it helps to ensure the survival of human infants. Man's new best friend? A forgotten Russian experiment in fox domestication discusses the experiments of Dmitri K. Belyaev in domesticating silver foxes. By selecting the tamest foxes from each generation he bred, he was ultimately able to breed foxes that enjoyed human interaction in much the same way dogs do. They had lower adrenaline levels than wild foxes along with altered coat coloration, and Belyaev hypothesized that the pathways for adrenaline and melanin were connected. This was later confirmed. Along with this change, these foxes had more neonatal characteristics than their wild counterparts such as licking their caretakers, staying playful longer, and altered skull shape. By breeding only the tamest animals when we first began to domesticate them, we most likely inadvertently created more neotany with each generation and grew more attached as a result.

As was discussed early on in the video, one of our first main reasons for wanting to domesticate animals was so that we could eat the same way we saw the top predators were eating. It was also mentioned that there was a point at which humans were afraid of even large herbivores because it is much more difficult to approach a wild animal than a domesticated one. We eventually domesticated these large herbivores and they would eventually be bred to become the modern horse and cow. However, attempts to domesticate similar large herbivores such as the zebra have been unsuccessful. Jarod Diamond suggests that all species that could possibly be domesticated share six traits: flexible diet, fast growth rate, pleasant disposition, the ability to breed in captivity, a social hierarchy, and no panic. When it comes to diet, herbivore diets have always been cheaper and easier to provide meaning that herbivores were fairly easy to feed in captivity. Carnivores had to be able to scavenge or hunt when humans couldn’t necessarily provide meat regularly, so cat and dog ancestors were able to take care of their own dietary needs pretty well. Almost all domesticated species reach sexual maturity within a matter of a couple of years or less depending on the species. We have bred animals that did not originally possess a pleasant disposition to have one now by selecting their tamest ancestors. All domesticated animals can breed in captivity, and many that we use for food are bred using artificial insemination to speed up the process and make it more efficient. Even animals like chickens have a social hierarchy, although social hierarchies are not necessarily as complicated in animals as they are in humans. Domesticated animals that are handled well and are not abused or neglected will generally not be panicky. These qualities that diamond came up with are the basis for what any animal needs in order to be domesticated, and every animal that humans have successfully domesticated seems to possess these qualities.

There are many factors that lead to the domestication of animals and the formation of the strong human-animal bond between pet and owner. We are lucky to have been able to use these factors to our advantage, and we can now enjoy food, clothes, companionship, and much more that would have been off limits without the help of domesticated animals.