Stallions self-mutilate, wild chimpanzees feel depressed, koalas acquire sexually transmitted diseases and wallabies get stoned.
Owing to our common evolution, human beings share many behaviors -- and disorders -- with denizens of the animal kingdom. Yet veterinarians and doctors rarely trade notes.
UCLA Health System cardiologist Barbara Natterson-Horowitz and science writer Kathryn Bowers spent five years researching the ways animal and human conditions can illuminate one another. The result is “Zoobiquity: What Animals Can Teach Us About Health and the Science of Healing.”
We spoke at Bloomberg world headquarters in New York.
Lundborg: In addition to cancer, heart disease and diabetes, animals have erectile dysfunction, obsessive- compulsive disorder, anorexia -- all kinds of psychiatric problems?
Bowers: Yes. But most physicians see animals and their diseases as somehow “different.”
But what is a physician -- a veterinarian who treats only one species.
Lundborg: How can it help us to look at animals?
Natterson-Horowitz: We could get new treatments or new perspectives if vets and physicians collaborated.
In human psychiatry, for example, cognitive behavioral therapy, or CBT, is really the rage. Who are greater experts than animal behaviorists?
A therapist with patients who burn themselves with cigarettes could talk shop with a bird specialist who treats parrots with feather-picking disorder.
Lundborg: What is deep homology?
Bowers: A term to describe the genetic kernels we share with nearly all creatures, so genes taken from a sighted mouse and placed into a blind fruit fly cause the insect to grow structurally accurate fly eyes.
All living creatures, including plants, are long-lost relatives.
Lundborg: Why do vets care more about sex than physicians?
Bowers: They see it as a marker of health, and it’s just folded into the animal’s daily life.
Natterson-Horowitz: Sometimes it’s easier to talk to your cardiovascular patients about whether they can walk up a flight of stairs carrying a bag of groceries instead of asking, “Are you having sex or are you having angina?”
Lundborg: The oldest penis on record was active 425 million years ago and belonged to a crustacean. What does the long evolutionary history mean for men?
Natterson-Horowitz: Every aspect of ourselves has emerged through hundreds of millions of years of natural selection, including our sexuality.
Mammals emerged about 200 million years ago -- if you’re a male mammal you have a penis, you get erections, you copulate, you ejaculate. The neurological sequence that has to happen to have an erection is conserved across mammals and other animals.
Lundborg: Not just mammals?
Bowers: That a turtle would have an erection in the same way that a human being would have is kind of astounding.
Lundborg: How did evolution shape sex?
Natterson-Horowitz: It’s evolutionary biology that underlies making connections between the central nervous system and the penis.
Over time it became more strategic in terms of becoming erect in response to opportunity and then detumescing, deflating in response to threat.
Lundborg: One barnacle has a penis 40 times the size of its body. So, how important is length?
Bowers: If you need to mate with a barnacle on the other side of the rock, it’s probably pretty important to have a long one. A barnacle in a roiling tide pool has a shorter, thicker penis.
There are certain bird species that have actually lost the penis because it seems to be aerodynamically not advantageous.
Lundborg: What does the animal kingdom tell you about erectile dysfunction and premature ejaculation?
Bowers: It tells you that it happens and it’s normal.
Lundborg: How did it get pathologized?
Natterson-Horowitz: I hope that the book can de-pathologize a number of conditions because people who suffer from ED or eating disorders or cancer or whatever it is, not only have to deal with the disorder but the shame and the self-recrimination and the guilt.
Knowing it all happens across species can for some people reduce that.
Lundborg: Animals also have sex for reasons other than procreation?
Bowers: The more we started looking at erection, ejaculation -- and orgasm in both sexes -- we started thinking about what would entice animals to engage in sexual activity. And the answer is pleasure. Feeling. Sensation.
Natterson-Horowitz: Masturbation is so common, from mammals to insects, and you also see lots and lots of same-sex activity.
In fact, most of the sexual activity in animals is non- procreative -- the reproductive aspect is a byproduct.
Lundborg: Why do animals deliberately hurt themselves?
Bowers: Most animals groom, and they release feel-good neurochemicals. When an animal gets stressed, those activities can increase.
They are trying to get more and more of that feeling and they end up actually hurting themselves.
Natterson-Horowitz: Cutters say it makes them feel relieved, it calms them, so it’s sort of grooming amplified. Pain also releases endorphins.
Lundborg: What does it tell us that animals get stoned?
Natterson-Horowitz: People with substance-abuse problems and addiction suffer so much blame.
But it’s a biologically driven disease, with a chemical reward system shared by other animals, from worms to primates, which has been in existence for millions of years.
Lundborg: Why did you write this love-letter to vets?
Natterson-Horowitz: I became a better doctor by working with veterinarians and I feel my colleagues should be reaching across the species divide and collaborating.
Most people love their veterinarians, and many patients actually say that they wish their physicians were more like their vets.
(Zinta Lundborg is an editor for Muse, the arts and leisure section of Bloomberg News. The opinions expressed are her own. This interview was adapted from a longer conversation.)
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