Cat and mouse and us

The Hemodynamic Cat battling a swinging light switch, photos by Ms. Dr. Hemodynamics; the HC in a quiet time.

Recently, the Hemodynamic Cat did something surprising: she caught a mouse.

I would like to say that I have never doubted the Hemodynamic Cat's mouse-catching abilities, but this is not the case. She spends a lot of time pouncing on and batting around her toy mice, in a way that suggests some inner ferocity. But her record on watching cockroaches with interest rather than hitting them, and her failure to show any evidence of actual mouse-catching, left me a little skeptical. I've come to love the HC for other reasons.

Recently, I was coming to bed and saw that the HC had a mouse in front of her, and was looking up at me expectantly, as she sometimes does when she wants me to play with her and her toy mice. Then I looked more closely and saw that it was too thin and small to be one of her toys; and that in fact it was breathing.

My experiences in an immunology lab left me well-prepared for this moment; I picked up the mouse by its tail, and eventually delivered it to a warm spot outside our apartment where I hoped it might be able to recover and go on living outside our apartment. It wasn't moving much, and I thought about more definitively snapping its neck--to finish the job that the HC had clearly started and end its suffering--but I wasn't sure that it might not be able to rally once no longer stressed and stunned, so I left it. I later found it definitively dead, in the same spot. The HC had killed the mouse.

I know that some cat owners think that the cat's habit of bringing dispatched prey to display to their owner is some outgrowth of wild cat mothering habits. In terms of the original wiring for the behavior, that's probably true--there has to be some "little tasty things I don't eat right away" circuit available to build on. But the wild forebears of domestic dogs also feed their puppies, and domestic dogs don't make a point of sharing their catch with their people in the same way that cats do.

I've always thought that this behavior is actually part of the social contract that cats and people developed with the origins of agricultural society. Recent genetic work confirms what can be surmised from history, archaeology, and anthropology: cats go with agriculture, not with hunting and gathering. When people started having grain silos, field mice started becoming silo mice, moving to where the concentrated bounty of the fields were stored. Cats followed the mice.

This seems like the moment in which the "show the mice" strategy would have been most useful. The social bond would not have come first, and so the showing of the mice is not a process of mistaking people for kittens. It is an act of seeking patronage. A cat who just seemed to wander around the village but did not show the mice she caught to anyone might be tolerated or even enjoyed. But I'm not sure that early agrarian societies would have put much energy into caring for that cat.

On the other hand, the cat who comes to the peasant farmer, drops mice at the door, and meows loudly with enthusiasm, is saying, "I am worth keeping around." What the cat loses in protein from the mouse not eaten, she gains in protein from the people who want to encourage her mouse-killing. People, and especially grain-farming people, want cats to kill many more mice than they need to support themselves; they want cats to kill every mouse in sight. The cat that brings mice is showing her dedication to this shared mission. The cats that are also social and charming get to live inside and sleep next to the warm bodies of the giant primates, but the "show the mouse" strategy might well have been the first step in the evolution of cat domestication.

Cat experts sometimes say that cats, unlike other domestic animals, domesticated themselves. This explains their more ambivalent attitude about human attention; cats have eliminated only the wildness that kept them out of the house, and sometimes not even that. The Hemodynamic Cat, her ancestors having been bred for the company of princesses, is an extremely social creature with the people she knows, but she still has a wariness of new people that shows the not-so-ancient wild cat inside her.

As I held the mouse by its tail, its lungs expanded and contracted and its little legs kicked. In retrospect, given that the mouse could not get up and walk anywhere after I set it down, I think the legs kicking might have been a lower spinal cord reflex arc. Maybe if something grabs a mouse's tail there is no need to wait for the brain to tell the leg muscles to start making running motions; but the mouse needs the brain to communicate with the spinal cord in order to coordinate its movements. A mouse is a tiny thing, but with all the wonder of mammalian evolution, and of its own special qualities. From scores of dissections, I could imagine its heart; its thin, wide diaphragm; and, as I found again and again in the lab, its comparatively large spleen, full of blood and immune cells. I didn't want to touch its fur--I didn't want to give it a chance to turn and bite me--but I could remember what touching a mouse felt like, the warm softness of it, the vitality of the quick-moving lungs and heart. The mouse was beautiful, as all mice are, and I mourned its demise.

Still, I don't want mice eating our food and having the run of our house. And so when the Hemodynamic Cat looked up at me, with the little gray field mouse breathing but laying still in front of her, I saw our cat with a new respect, and felt something ancient: our cat was earning her keep.

Our social contract forged between two species, once seemingly consisting only of bonds of affection, had renewed its ancient preamble. I had thought that I loved the Hemodynamic Cat for her inherent value as a creature, and for her love of us, whether or not she caught mice. As I took the mouse out of the apartment, I realized that I now not only loved her, but respected her in a new way. Good job, I told the Hemodynamic Cat, and she said, "Mrowww!" back. I had killed mice for science. The Hemodynamic Cat had done something much more intimate and powerful: she killed a mouse for us.

How I changed, part 1: life and death

"Any animal’s minute-by-minute life is a constant process—or actually, a system of many interlocked processes. All of us animals are constantly kept alive by our systems of life." Video: the Hemodynamic Cat takes a nap.

“This process must have changed you,” my friend R said, as we were talking about my upcoming graduation from medical school. “But how did it change you?”

I’ve been thinking about that ever since, and I’ll be thinking about it more—this surely won’t be the last that I write about it.

* * *

Life and death changed around me even in pre-medical biology classes, but much more acutely as a medical student. Walking along a crowded beach, or out in nature, or even sometimes in the city, I much more frequently and knowledgeably remind myself of the physiology of the life around me. There are the big bipedal apes (you know, us); the birds; the dogs; the fish in the sea. When I see a dog running down the beach, or children splashing in the waves, or a row of birds flying in formation, I am much more likely now to remember how they are able to do these things. Their hearts are beating, their lungs are taking in oxygen, the mitochondria of their cells are using the oxygen for biochemical reactions which allow them to store energy, and the cells of the brain are using that energy to direct the activity of the rest of the body.

Any animal’s minute-by-minute life is a constant process—or actually, a system of many interlocked processes. All of us animals are constantly kept alive by our systems of life. Those systems are so complex that even after a lifetime of me learning about the biology of people alone (never mind birds, or dogs, or fish), I will die having learned only about a fraction of the cells and molecules and organs that will have kept me alive until that moment.

And if any of it stopped for any of the animals around me, the whole scene would change. A bird would fall into the water. A man would fall down on the beach. A dog would stop moving. The change from my previous life is that I more frequently remember that these underlying processes must constantly be working to allow the life around me to keep living. I more reliably remember some basic information about how these processes work. And so I more often appreciate that their workings all around me—the panting of the dog, the shouting of the children, the bird using its muscles to flap its wings—are each made possible by still more mechanisms. I more frequently notice and love the baroque and beautiful details of life.

* * *

I came to understand emotionally—and not just intellectually—that life is not the default. In fact, life is an improbable and incredible struggle made possible only by a constant cooperative struggle of cells working against the processes of entropy. Death no longer surprises me, though it still can upset me.

I first began to understand my own mortality at around the time a lot of people do, in my early twenties. But my understanding began in the midst of the HIV epidemic. Before medical school, I devoted a great deal of my work life and much of my volunteer civic energy to the cause of preventing new HIV infections. And partly because my consciousness of death came from HIV in the early 1990s, I was always conscious of the possibility of death, but I was always engaged in the effort to prevent it.

A few years after I started doing HIV prevention work, a high school friend of mine was diagnosed with metastatic cancer. I was not much involved in her care, and although we stayed friendly throughout, her social world contracted to a small circle in which I was not usually included. The one thing that my partner of the time and I were able to do to help was to find her and her boyfriend an apartment in San Francisco, which at the time was no small feat. The apartment was immediately below us, so although I did not see her socially very often, I saw her through windows or during comings and goings, and saw her getting more and more skinny and weak. I saw her boyfriend going through many stages of worry and grief. I knew when she died.

Though I knew intellectually that it shouldn’t, emotionally her diagnosis and death surprised me. My friend seemed like a buckle-the-seatbelts, wear-your-condoms sort of person; she won lots of the good student awards in high school. My surprise and shock about her death helped me see that my public health work had an irrational emotional abscess festering within it: the hope that somehow everyone could be saved from death if we all just behaved ourselves. Looking back, I think that her death was one part of my trajectory towards medicine. It helped me towards the very beginning of realizing emotionally and viscerally that death and suffering is a part of life--and not just the product of a particular epidemic that had to be stopped.

When I got to medical school, death gradually became much more a part of my regular experience. Two different anatomy classes (the required one and an optional one) meant that I dissected two different bodies. This required a very lengthy and detailed involvement with the bodies. And that meant a close-up constant literal immersion in the fact of death.

Then there were my patients, many of whom were dying, facing life-threatening diagnoses, or fearing the possibility of death; and some of whom died. I actually gravitated towards some of this in medical school. I took more oncology-related rotations than most people do, and I did an ICU rotation. Before death, there were worries; struggles with families and within families; various forms of physical suffering, and even more forms of emotional suffering. Death started to seem like the simple part. Living near death is much more difficult and complicated.

From being immersed in the bodies of my two anatomical donors, and then also from physical exams, Pap smears, stitching up wounds and draining abscesses, and standing next to surgeons in the OR trying to make myself useful, I got the immediate and now deeply-remembered sense of the physicality of our bodies. Before medical school, I was moved and fascinated by the fact that we were only frail physical bodies. I once wrote a kind of prose poem about it, which I must have in an old notebook somewhere. But I did not regularly make the emotional leap from my intellectual or poetic understanding of this frailty. That emotional leap required learning biology. It required knowing in detail the ways in which we are physical beings. Knowing these details convinced not only my intellect but my emotions that our physical selves must eventually cease to exist.

I am not a religious person: I believe that who we are is contained by our physical selves. Biology is the beginning and end of life, and it is life itself. We live because our cells work. We die because of the built-in limits of our cells and the systems they make. Even those limits are part of our biology.

It shouldn’t be a surprise to me that going to medical school helped me understand life and death in a different way. But I think I hoped when I started that the understanding would come as a mystical or philosophical insight, or some spiritual catharsis on a call night. That’s not what happened. Instead, I learned biology, and learned more biology, and then I started seeing life as biology, and biology as life.

How we feel about all of this, and what we say to each other about it, is important; but how we feel and what we say is also part of the beautiful biology of long-lived social animals. We are bipedal apes; we use tools and language; our hearts beat. Like pelicans and elephants, we are born, we live together, and then we die.

Photo: based on their behaviors, it seems reasonable to believe that elephants mourn the dead.

Cat whisperer

YouTube, aka, HundredsofThousandsOfMoviesOfPeoplesCats.com, has this video which more or less illustrates the content of my conversations with the Hemodynamic Cat, except this guy has two.

Ms Hemodynamics is off on vacation with her mom, so I am staying in the Hemodynamics HQ with the Hemodynamic Cat. The Hemodynamic Cat is a Siamese cat, and like many others who share her ancestry, she has a strong personality. She also seems to have strong opinions which she expresses quite forcefully with sometimes unstoppable loud meowing.

The meow-screeds are sometimes especially unrelenting when Ms Hemodynamics is away. She was Ms Hemodynamics' cat before I came into the picture, and initially waged an incredibly stealthy and devastating terrorist campaign against me to try to stop me from dislodging her from her place as Ms Hemodynamics' BFF. We get along very nicely now that she realizes that even if I dislodged her from her pillow, I would never dislodge her from Ms Hemodynamics' heart. Still, I think she is just slightly more uncomfortable with me, so that she can not decide whether she wants me to reassure her in Ms Hemodynamics' absence, or whether she just wants Ms Hemodynamics to return now and wants to express her opinion about this, or whether she would prefer that I leave her alone to think about Ms Hemodynamics on her own.

This can sometimes become upsetting. When I can not seem to satisfy the gnawing discontent in the Hemodynamic Cat's soul, and she keeps yelling despite my best efforts, I sometimes wonder about the wisdom of becoming a father. (Her meowing can become intensely distressing, and seems to have evolved to resemble the cry of a human baby. It takes real determination to ignore it.)

There are a few tactics which work, but I've recently discovered one that works the best, but is kind of distressing. And it reminds me of a nasty doctor trick.

When cats are content, they make a big long blink of the eyes. And for cats, this signal is contagious, like a yawn, and it seems to be strongly communicative. At some point in the last two days I started doing this to the HC when she was on a tear of yelling. And most of the time she has this reaction:
1. Looks at me insistently, and meows one or two more times loudly.
2. As I continue slowly blinking, she sits and looks down at the floor in a kind of gesture of disappointment, like when we leave the apartment and she realizes that we are leaving.
3. Meows a few more times, but with a quieter, sadder, hoarser tone.
4. Gives up and walks away.

In other words, I think I've figured out how to communicate in cat terms: "I'm content. What's your problem?"

Which, really, is not very nice. It's like when people come in to a doctor's office all freaked out and worried and the doctor says, "I'm not worried at all. You are 100% healthy." And then won't elaborate.

I started feeling a little bad, and now I resolved that there have to be many repetitions of "pick cat up, cat purrs, cat wriggles out of my arms, cat walks around the house, cat comes back and starts yelling again" before I try this tactic. After all, since she's yelling, I'm not at all content. And it's not nice to lie--especially to cats.