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What do we really know about suicide in nonhuman animals and their concept of death?
Although stories about suicidal animals are anecdotal, what matters is that they are perfectly plausible from the standpoint of contemporary science (Preti 2011a, p. 819). Thus, even if we cannot currently prove that any animal has committed suicide as a matter of fact, there is a large and growing body of evidence indicating that this possibility cannot be ruled out as a matter of principle.—David M. Peña-Guzmán, 2017
Recent discussions about whether nonhuman animals commit suicide raise many fascinating and important questions about what they know about their own and others' deaths and dying. In Dr. Jessica Pierce's excellent essay called "A New Look at Animal Suicide," she correctly notes, "Although many people are quick to brush off the question 'can animals commit suicide?' as silly, and as fantastically anthropomorphic, we ought to stop and give the question some serious thought." Her piece resulted in my receiving a few emails about the possibility of animals committing suicide, two of which were written as follows: "Do animals really know they're gonna die?" and "Do animals have the same concept of death that we do?"
Dr. Pierce's essay was motivated by a thought-provoking piece by philosopher Dr. David Peña-Guzmán, "Can nonhuman animals commit suicide?" In the essay, he concludes there are scientific and philosophical reasons that support the idea that nonhumans can cause self-harm and their own death that also apply to humans. He writes:
"Many people believe that only humans have the cognitive and behavioral capacities needed for suicidal behavior, such as reflexive subjectivity, free will, intentionality, or awareness of death. Three counterarguments—based on (i) negative emotions and psychopathologies among nonhuman animals, (ii) the nature of self-destructive behavior, and (iii) the problem of model fidelity in suicide research—suggest that self-destructive and self-injurious behaviors among human and nonhuman animals vary along a continuum."
His essay and associated commentaries are available online, as is Dr. Pierce's.
Something's got to give concerning human exceptionalism
Dr. Peña-Guzmán's reasoning is consistent with Charles Darwin's ideas about evolutionary continuity that stress that in many contexts, differences among members of various species are differences in degree rather than kind. They are shades of gray, rather than stark black and white differences, that means that we need to keep an open mind about the cognitive and emotional capacities of other animals and how they are very similar to our own (for more discussion please see "Animal Minds and the Foible of Human Exceptionalism" and links therein).
Concerning supposed human uniqueness and superiority, Dr. Peña-Guzmán writes:
One could argue that in the case of the animal sciences, this bias manifests itself primarily as an anti-confirmation bias that inclines us to be hyper-skeptical of ideas that challenge our belief in our presumed uniqueness and superiority. In our minds, such ideas never get confirmed—no matter how much support they might have. This bias puts suicide researchers in a double bind since they must take a position on whether the link between negative emotions and self-destructive behaviors exists in both humans and nonhuman animals...
I agree 100 percent with Drs. Peña-Guzmán and Pierce's conclusion that we need to keep an open mind about whether or not nonhumans actually commit suicide. In July 2012, I wrote an essay titled "Did a Female Burro Commit Suicide?" based on a story I was told by Cathy Manning about a burro who seemed to kill herself after she gave birth to a baby with a harelip. The infant couldn't be revived and Cathy watched the mother walk into a lake and drown.
"Do animals really know they're gonna die?" and "Do animals have the same concept of death that we do?"
Among the emails I received concerning Dr. Pierce's essay, I selected two because they raise profoundly important questions that are very difficult to answer with any certainty given what we know right now. The other questions I received could be easily folded into these two general queries.
Concerning the questions: "Do animals really know they're gonna die?" and "Do animals have the same concept of death that we do?" I don't know, and I'm not sure anyone else does either. This does not mean they don't, but I don't know of any research that conclusively shows they do. When I've talked to a few people about these possibilities during the past few years, I find myself resisting answering these sorts of questions with a definitive "yes" or a definitive "no." Living in that troubling gray zone of uncertainty—maybe they do and maybe they don't—makes me keep an open mind about the cognitive and emotional capacities nonhumans have that may inform themselves about their own demise and what they know about when others have died and aren't coming back. It also keeps me up at night sometimes wondering just who other animals are and what do they really know about a lot of other things that happen in their fascinating lives.
When someone really pushes me and wants more definitive answers, I find myself answering: "I don't think that any nonhuman animal ponders that they have a finite life like humans do." But I immediately qualify that statement by clearly saying: "I really don't know and I don't think anyone else does at this time." And, I also don't think that any nonhuman knows another individual is gone forever, that their lives are over, but the key word here is think.
That darned gray zone of uncertainty—maybe they do and maybe they don't—just doesn't go away
So, are humans exceptional among mammals and other nonhumans in having a more developed concept of their own and others' deaths? If pushed, I think they just may be, but once again, the keywords are may be. While I know that many nonhumans grieve and mourn the loss of other individuals, I also don't know that they know that the deceased are gone forever.
What other animals are thinking and feeling when they're deeply saddened when another animal dies isn't clear, but it's obvious that a wide variety of animals suffer the loss of family and friends. Cathy's story about the burro who drowned herself, and others, some of which are discussed by Dr. Peña-Guzmán, made me rethink the question of whether or not animals commit suicide, and I hope these stories and others offered by citizen scientists open the door for some informed discussion and comparative research about this intriguing possibility. We must pay careful attention to stories that have a common theme, and hope they will stimulate more research in a given area. We also need to think more about when a difference in degree becomes a difference in kind, but that's a thorny topic for future essays.
I'm deeply indebted to Drs. Peña-Guzmán and Pierce for writing their thoughtful pieces and for their open minds on matters of animal suicide. I'm also thankful for those who take questions about animal suicide seriously and who keep an open mind. When I carefully study what we know about animal suicide and what nonhumans know about their own and others demise, I think it's too early to offer any definite answers to the questions: "Do animals really know they're gonna die?" and "Do animals have the same concept of death that we do?" I'm in total agreement with Dr. Pierce when she writes: "Although many people are quick to brush off the question 'can animals commit suicide?' as silly, and as fantastically anthropomorphic, we ought to stop and give the question some serious thought."
Please stay tuned for more discussions about the cognitive and emotional lives of other animals. There's still so much to learn, and, it's clear from a good deal of detailed comparative research on other animals, we surely are not alone and are not exceptional in having evolved many highly sophisticated cognitive skills and complex emotions.
