How Looking to Animals Can Improve Human Medicine

In a new book, UCLA cardiologist Barbara Natterson-Horowitz reminds us that humans are animals too. Now, if only other doctors could think that way

Studying animals can help greatly with the advancement of human medicine. (Richard Hutchings / Corbis)

(Continued from page 1)

It is very hard to surprise me anymore, because I pretty much assume that nothing is uniquely human. Hypertrophic cardiomyopathy, the heart muscle problem that sometimes sadly results in the death of a high school athlete, occurs in a number of animal species. Similarly, some exotic animals seem to be predisposed to breast cancer. Jaguars, tigers and lions seem to have an elevated incidence of breast cancer and ovarian cancer.

We were really interested in obesity. Companion animals are getting fatter. Some felines are put on a high protein, low carb diet that veterinarians call the “Catkins” diet. Obese dogs occasionally get liposuction, and in some zoos around the country, animals are put on a Weight Watchers points-type system. Maybe it’s less surprising that the animals under our care are getting heavier, because we are as humans. But we asked, do wild animals get fat? We learned a lot about some animal populations that do indeed seem to be getting fatter, but also the natural cycle of fattening and thinning in the wild. There are many takeaways for human patients who are struggling with weight.

We looked at substance seeking or addiction. Do animals ever seek substances to alter their sensory states [much like humans seek out drugs or alcohol]? Bighorn sheep will scale very steep cliffs to get access to this psychoactive lichen that grows on the rocks. They grind down their teeth to get it onto their gums. Waxwing birds are notorious for ingesting fermented berries and flying while intoxicated. Then, some domestic dogs seek out wild toads to lick the hallucinogenic chemicals off their skin.

We are more alike than we sometimes think, right?

When I was going through my education, undergraduate and graduate school and med school, we were given very stern warnings against the tantalizing pull to anthropomorphize. Back then, if you saw a behavior or a facial expression on an animal and gave it a human characteristic you risked being viewed as unscientific and sentimental. You are just projecting.

But that is already a few decades ago, and there have been a lot of advances in neuroscience, molecular biology and comparative genomics. It is time that we update that view. I think we haven’t embraced our animal natures enough. When we do see similarities, we need to maintain scientific skepticism, of course. But we can also expand our view a little bit and consider what is anthropomorphizing and what might actually be recognizing a shared evolutionary legacy.

One of the arcs of the Zoobiquity story is to acknowledge our own ignorance and to then turn on the lights—to say wait a minute, let’s look at this. We are linked by evolution. We are linked through environment. We share the vast majority of our DNA with other animals, certainly with mammals but also with reptiles and even fish. So, is it really surprising that the clinical syndromes of animals and humans are the same? We’ve found that people catch on pretty quickly.

What are the benefits of a zoobiquitous approach?

When I was a psychiatrist I took care of a number of human patients who injured themselves. Psychiatrists sometimes call this behavior “cutting.” Until I wrote Zoobiquity, I assumed that this was a uniquely human behavior. I subsequently learned that self-injury is seen in quite a spectrum of different animal species. Horses, when they are stressed, isolated or bored, can engage in a behavior called flank biting. It is serious and can cause significant injury to the horses. Veterinarians have some very specific ideas about what triggers self-injury and importantly some very specific and highly effective ways of helping the animal decrease the behavior.

It was fascinating to learn that there is a syndrome in pigs called thin sow syndrome. Occasionally, a pig that is under social stress will decrease food consumption and start to lose weight. For females, the syndrome can also be associated with the animal not going into estrus, which is an interesting potential analog to what happens in some human anorexic females. They will stop menstruating. In some instances, the pigs will actually go on to starve themselves. Interestingly, farmers have specific ways of identifying risk factors for the syndrome and specific interventions. I think that would be the kind of information psychiatrists and psychotherapists would be interested in having.


Comment on this Story

comments powered by Disqus