January 2009

Barbara J. King


Biology of the Animal-Human Bond: Overdosing on Oxytocin

How I longed for a brain bath of oxytocin to cushion my reading of Made for Each Other: The Biology of the Human-Animal Bond. In it, Meg Daley Olmert asks a most fascinating question: How can our biology help explain why we humans are enthralled with animals? Olmert’s answer tacks between lovely descriptions of emotional relating between humans and animals, and an unlovely relentless biologizing that invests the chemical oxytocin with such power that the transformative force of flesh-and-blood creatures acting together pales in significance next to it. 

Olmert tells us that the hormone enabler of labor-and-lactation, oxytocin, can:   

* Lower heart rate and stress hormones
* Enable a mother to see herself in her newborn, “a flash of recognition that will inspire her” to protect the baby
* Make people more trusting and trustworthy
* Make a primatologist want to live with baboons in Africa, and made her want to understand and be understood by them
* In short, “Make us smarter, calmer, friendlier, healthier, even more attractive”

See, then, how Olmert chooses verbs of cascading causation? For her, what’s made or enabled by oxytocin are not mere physiological states but instead whole worlds of positive feeling and becoming. This view infuses her twin theses: When animals and humans come together, oxytocin blooms. And at certain points in prehistory and history, new milestones were reached by evolving humans that ramped up these oxytocin blooms and allowed human-animal relating to go one level deeper. When we began to hunt, to domesticate other species, or to take pets in our homes, our cross-species chemistry changed in specific ways.

I felt at sea, reading Made for Each Other. Days before I crack open an advance copy, I had mailed off my new, long-in-the-works book manuscript on the spirituality of human-animal relating in evolutionary perspective. My topic differs from Olmert’s but overlaps with it, and I eagerly anticipated learning new things from her.

Olmert’s writing at times warmed me with pleasure. Her section on the horse whisperer Ray Hunt deftly describes his defusing of the jitters exhibited by hypersensitive horses, indeed of their “mighty evolutionary prejudice” against a species that too often killed them in the past (ours). Olmert brings to vivid life our past, as when she envisions a social gathering in prehistoric Ukraine: “Here, under vaults of great arched ribs mounted atop stacks of giant mandibles, skulls, hips, and scapulae -- under twenty-three tons of bone -- [our ancestors] wrapped themselves in the hides of their kills and dreamt dreams we will never have.” 

Yet the scientist in me felt chilled too often, rather than warmed. Daring leaps from other mammals’ biology to human biology are leaps too huge. Experiments with pine voles led scientists to “conclude that exposure to endocrine disrupters can alter brain circuitry and behavior associated with monogamy. Humans are monogamous and are not immune to the devastating social effects of a disrupted oxytocin system.” For someone who cautions her students to avoid 1:1 comparisons between other primates and humans, a comparison between vole monogamy and human monogamy was discomfiting.   

Some passages stopped me cold. Olmert’s language, as I have already mentioned, tends to empower the parts (chemicals) rather than the living and breathing wholes (creatures engaged in their dynamic dance with each other). Early on, with a disciple’s adoration, Olmert approves E.O. Wilson’s concept of biophilia, the notion that we are “genetically predisposed to be fascinated by the living world around us.” In Olmert’s hands a predisposition is wielded with blunt force: “How could this serious scientist have reached any other conclusion [about innateness],” she asks, “when, at the age of nine, young Wilson was overcome by the urge to stare at ants?”

What’s missing here are developmental dynamics. A child’s life is comprised of a tangle of influences from family, school, and peers, of the mysterious interior poetry that pushes him towards one thing and not another, of our evolutionary predilections too. On an account focused on the innate, the interesting stuff goes unanswered: What kept Wilson staring at ants so long and insightfully that he (and not other 9-year-old “preprogrammed” boys) became a world-renowned biologist?  

This demonstration of Olmert’s reasoning is instructive and predictive, for repeatedly she verges on a grasp of the biocultural web of influences on behavior, only to fall back under chemistry’s spell. Let’s look at a trio of examples:

* Maternal care: One thread through the book is that, in mammals “a powerful attraction to and empathy for babies is evidence of a mind focused by oxytocin.” Olmert’s language (here and elsewhere) puts oxytocin in the driver’s seat. Yet she also cites research by Michael Meaney and colleagues on rats showing that “increased maternal care developed greater densities of oxytocin receptors in brain regions known to regulate maternal behavior, fear, and stress.” Here the causal arrow reverses: it’s gentle touch that changes biology. More to the point, it’s in the context of a dynamic system of biology and culture that behavioral change happens.   

* Aggression and its regulation: The Fulani people of Africa relate closely with the cattle they raise. Herd control comes about by methods including stick-hitting. However, one on one, Fulani herders soothingly stroke their animals’ heads and necks, and even the inside of the back leg, mimicking how a mother licks her calf. “The animals welcome these nurturing moments,” Olmert writes, “standing transfixed, and even lick their owners in return. These simple acts of kindness physiologically release the oxytocin that then expands the level of understanding between the two species.” Olmert concludes that the cattle have a “socializing effect” on the people who tend them, but this comes just after a description of the Fulani as having a “fierce reputation” and as being “easily provoked” so that “even minor offenses [are] challenged with physical confrontation.” Seems there’s a little more going on here than oxytocin making us friendlier! Oxytocin’s effects are moderated by behaviors expressed as part of intricate cultural traditions. 

* Kids and autism: Friendly dogs, it has been found, have a strong positive effect on autistic children. One study shows that if autistic children met with their therapist and a dog, their autistic symptoms diminished. “But all these marvelous gains,” admits Olmert, “were lost when the dog was removed from the therapy sessions.”

Let’s cut to the chase: Oxytocin can produce short-term changes in mood, affect, and experience. To deny this, to deny that our biology can affect our bodies, our brains, and even our behaviors, would be a mistake worthy of scientific illiteracy. But what that short-term change amounts to is an opportunity, a kind of hopeful platform from which individuals --  mothers and their babies, herders and their cattle, developmentally challenged children and their therapists -- can build positive changes via sustained patterns of emotional meaning-making.

If Olmert is right, and “human-human interactions are becoming more and more endangered” in our cyber-obsessed, interaction-at-a-distance society, is the answer a “sea of oxytocin [to] wash over all of us”? Have we grasped the lessons, I wonder, of The Century of the Gene? Author Evelyn Fox Keller tells how the conceptualizing of genes as discrete and powerful blueprints for behavior turned out to be severely misguided (for all the reasons of developmental dynamics I’ve recounted here and more). Are we headed down this same road again in the 21st century, this time empowering neurochemicals like oxytocin?  

A final note of caution: Heartwarming animal tales co-exist in Made for Each Other with others where rats are genetically manipulated, shocked with electricity, and injected repeatedly with neurochemicals. No doubt approved by animal-care committees at some research institution, these experiments and others like them were hard for me to take. If they bothered Olmert, she didn’t say.   

Made for Each Other turns a bright light on animal-human relationships, and raises provocative questions about the relationship of biology and behavior. I just think its science is the wrong way ‘round where it matters the most.

--Barbara J. King invites comments on her essays, at bjking09@gmail.com