Our relationship with death is a complex one. At an intellectual level, we understand our mortality, yet we go to great lengths to banish the notion from our minds. In most circumstances it’s a taboo subject for conversation. At the same time, we have elaborate rituals around death, and it inspires all manner of art, literature, music, and more. (Think Prince Hamlet’s “To be or not to be” speech, Mozart’s “Requiem,” and the Great Pyramid of Giza.)
And what of our animal cousins? When Charles, a western lowland gorilla, died in the Toronto Zoo last year, did his fellow primates mourn his passing? What does a gazelle think when a member of its herd becomes a lion’s dinner? Questions like these have been very much on the mind of the Spanish philosopher Susana Monsó, whose new book, “Playing Possum: How Animals Understand Death,” invites the reader to think about death from the point of view of the creatures we share the planet with.
While Monsó is a philosopher, her investigation draws on empirical studies from various scientific disciplines. Being a philosopher may even give her an edge, as it allows her to incorporate knowledge from many different fields. The philosophy of animal minds is relatively young discipline, yet a valuable one, Monsó argues, as it “works in dialog with science, reflecting on the methodologies with which we study the behavior and cognition of other species, identifying potential biases, and aiming to provide conceptual clarity.”
The first of these potential biases is anthropocentrism — the tendency to view everything from a human perspective. (Many studies have focused on grief, Monsó notes, because humans grieve — but she pushes back against the idea that an animal’s reaction to death needs to be human-like in order to be interesting.)
Then there’s anthropomorphism — the tendency to bestow an animal (or other non-human) with a human quality that it may lack. (This is an everyday feature of fiction, from George Orwell’s “Animal Farm” to Snoopy’s ability to fight the Red Baron.) Yet the opposite tendency can also be a problem: The author warns us against anthropectomy — the mistaken denial of a human-like characteristic that an animal may actually possess. “Both mistakes are equally serious, and there is no reason to fear one over the other,” Monsó writes. “They are both false descriptions of reality.”
With these warnings in mind, what can we conclude from the myriad of responses to death that can be observed in the animal world?
Monsó points out that some of these reactions happen on autopilot, so to speak. Ants, for example, will remove a dead ant from their nest (a behavior known as necrophoresis), but they appear to be merely responding to a chemical emitted by the corpse. (This has been tested by applying a drop of oleic acid to a live ant, causing its fellow ants to treat it as though it was dead.)
Monsó warns us against anthropectomy — the mistaken denial of a human-like characteristic that an animal actually possesses.
Chimpanzees, in contrast, display a much greater diversity of reactions to death. Monsó describes how the chimps in a sanctuary reacted to the death of an adolescent in their group. “Some chimpanzees inspected the carcass with apparent interest,” she writes. “Others simply sat around the body and observed it in silence. Some gave alarm calls. Others reacted aggressively, engaging in dominance displays and even attacking the remains.” Later, at feeding time, most of the chimps left the area; only a mother and daughter, who had been close to the chimp that died, remained next to the corpse. Monsó says these are examples of “cognitive reactions” to death, as contrasted with the “stereotypical reactions” seen in ants.
The arguments are occasionally quite subtle. For example, in order to understand the idea that death is irreversible, must a creature have some awareness of past and future? Not necessarily; Monsó believes the two concepts can be thought of as independent from one another. She writes: “This is because processing irreversibility is nothing but the recategorization of an animal from the class of individuals from which one expects the typical functions of her species to the class of individuals from which one does not expect these functions.” This recategorization is crucial, she explains, as it allows an animal to distinguish between an animal that’s merely asleep, or in some other dormant state, from one that’s dead.
Each chapter is fascinating, but the second-to-last chapter, on violence and predation, is especially interesting. First, Monsó reminds us that, while death often happens out of sight in the human world, this is far from the case among non-human animals. And the killer might be a member of one’s own species: Chimps and other primates raid other chimps’ territories; they’ve also been known to gang up on, and kill, their own alpha member.
Monsó also notes the ways that certain animals evade predators — including the opossum that gives the book its title. While many animals have an ability to stop moving and appear paralyzed when threatened — what biologists call tonic immobility — certain animals, like the opossum, can go much further, putting on elaborate displays of “playing dead,” a phenomenon known as thanatosis. Monsó describes the opossum’s performance in detail. The animal will curl up, with its eyes and mouth open and its tongue hanging out. “In this pose, she stops responding to the world and starts to salivate, urinate, defecate, and expel a repugnant smelling green goo from her anal glands.”
Importantly, the opossum likely doesn’t understand that it’s playing dead; it’s just acting out an evolved response, like the ants carrying a dead ant out of the nest. Monsó explains the survival advantage this ability confers on the opossum: Over millions of years, those opossums best able to feign death would have been most likely to survive an encounter with a dangerous predator. But, critically, the predator must have some conception of death in order to choose not to eat the dead-acting opossum. Monsó writes: “The opossum might not have a concept of death, but we can be pretty sure that at least some of those animals who intended to feed on her throughout evolutionary history did.”
Charles Darwin once described his masterwork “On the Origin of Species” as “one long argument” for the role of natural selection in evolution. While Monsó does not mention Darwin, her book’s structure does seem to echo the kind of step-by-step argumentation found in “Origin.” Chapter by chapter, the author lays out the case for animals having some conception of death, gradually honing in on exactly what that conception is, and how it may vary from species to species.
The opossum likely doesn’t understand that it’s playing dead; it’s just acting out an evolved response.
At the risk of giving away the ending, Monsó concludes that there may be certain aspects of understanding death that are unique to our own species. One of these is an understanding of the inevitability of death (we not only know that creatures can die, but that we ourselves actually will die at some point); another is the unpredictability of death (in general, we do not know in advance precisely when we will die). Even so, we are far from being the only creature that has some awareness of life’s fragility. The concept of death, she suggests, “is much easier to acquire than has usually been presupposed and is likely to be widespread in the animal kingdom.”
Many zoo visitors have likely asked themselves at some point, “What are they thinking? How much do they understand about their lives?” While we can never truly get inside the head of another creature, “Playing Possum” does an admirable job of illuminating one specific facet of animal consciousness. It’s one of those rare nonfiction works that will have some readers saying, “Why didn’t anyone write this book before now?”
