Are chimpanzees spiritual?
It's a question that Jane Goodall made famous by proposing that the rhythmic swaying and rock-throwing by chimpanzees at waterfalls in Gombe, Tanzania, is an expression of awe and wonder — of spirituality.
It's a question, too, that takes on new twists and turns as new data come in. In 2016, a group of 80 scientists reported in Scientific Reports that chimpanzees at four sites across West Africa cache stones and throw them repeatedly at trees. One of those scientists, Laura Kehoe, who is now a postdoctoral researcher at the Baum Lab at the University of Victoria, earned global media headlines for a passage she included when writing a post at The Conversation:
"Maybe we found the first evidence of chimpanzees creating a kind of shrine that could indicate sacred trees. Indigenous West African people have stone collections at 'sacred' trees and such man-made stone collections are commonly observed across the world and look eerily similar to what we have discovered here."
My response to this passage was skepticism, both at The Atlantic and here at 13.7, because the leap from "potential chimpanzee stone-throwing ritual" to "sacred trees" is just too great for me.
Fast forward to last month, when Wisconsin Public Radio's Steve Paulson aired an interview with Kehoe at To the Best of Our Knowledge. Kehoe described the basics for Paulson's audience: how chimpanzees in Guinea, often but not exclusively adult males, throw large (8 kg. to 9 kg.) stones at selected trees repeatedly, and sometimes place the stones in a tree cavity instead of hurling them. Could this be a ritual with a spiritual dimension? Could the trees be shrines? "Plausibility shouldn't be mistaken for proof," Kehoe replied to Paulson. "I do think that it's a possibility — some things can seem unlikely until they are discovered."
In the same segment, Paulson also interviewed me and primatologist Frans de Waal. We each suggested simpler explanations like apes wishing to impress an audience of other apes, or pure pleasure in aimed throwing at trees.
But then an interesting thing happened. Kehoe reached out to me by email to express her regret about how her views on stone-throwing have been presented in the media, including in Paulson's interview, which, she felt, focused disproportionately on the spirituality angle at the expense of other possible explanations that she offered.
When I communicated this — with Kehoe's permission — to Paulson, he pointed out that he had "left in [the interview] her comments about this being a highly speculative possibility — something worth considering — and her dislike of the newspaper headline about chimps finding God."
But here's the main point, and a surprising one: Kehoe told me that she doesn't, in fact, really think that the spirituality explanation is the most likely one at all.
I followed up by asking questions of Kehoe, who started by noting that her own observations in Guinea — at a site part of the Pan African Program with 34 chimpanzee field locations across Africa — came about through collaborative research:
"Our field guide, Mamadou Alioh Bah, first spotted the marks on a hollow tree. Lucy D'Auvergne (an experienced primatologist) and I decided to set-up a motion-activated camera and caught the elusive behavior on tape a few weeks later."
What range of explanations, I asked, does she think are reasonable to consider for the stone-throwing behavior, and which does she find most likely? She answered:
"This is the first time we have found chimpanzees repeatedly using stones at specific sites — with no relation to finding food. I think it most likely came about as part of a male display and could be related to long-distance communication — as there aren't many roots with large buttresses for drumming in this area and the sound of a stone hitting a hollow tree may carry better in a savannah ecosystem.
It is also possible that the stone accumulations may serve as some kind of territorial landmarks. However, both of these theories are tricky to test given that many of these sites are outside of protected areas and undergoing local habitat loss."
The notion of chimpanzee spirituality, Kehoe thinks, "simply makes for a more riveting story" than the other more pedestrian explanations. She continued:
"Of course, it is partly my fault for alluding to the possibility that this mysterious behavior could be linked to something sacred — this is because these sites are superficially very similar to human stone accumulations at 'sacred' trees. While I do think this aspect is worth pondering, it is a highly speculative remark that is by far one of the least likely explanations to this behavior. It has no concrete evidence."
So, if a person closely associated with the idea of chimpanzee spirituality doesn't after all think it's likely, where does that leave us? Well, with several things:
With Goodall's enduring view, of course.
With the remark of James Harrod, also interviewed by Paulson, that chimpanzees "of course" have an experience of religion (not just spirituality) because they experience reverence, awe, and wonder in the ways Goodall described.
With the fascinating scholarship of Donovan Schaefer, that claims also full-on religion for chimpanzees, and which I described in my piece for The Atlantic:
"Religion is something we feel in and express with our whole bodies, Schaefer insists, and once we realize this, we are free to see religion in other animals in certain instances of their embodied and emotional practices."
And for that matter, with Paulson's own view. (Yes, I turned the tables and interviewed the interviewer). Paulson told me this by email on Monday:
"While science can tell us a great deal about the evolutionary benefits of religion — and even certain brain functions that happen during spiritual experiences — it has little to tell us about the nature of the experience itself. Consciousness remains a huge mystery, and spiritual experience is part of that mystery. So if spiritual experience among humans is largely beyond the capacity of science to explain, why do we assume that chimpanzee spirituality is strictly a science question?
None of [the points raised in discussion] proves that chimpanzees have spiritual experiences or a sense of the sacred. But given all that we've learned about chimpanzees over the last 50 years — and how they keep surprising us — why should we assume that they don't also have transcendent experiences? That would seem to be a tantalizing possibility that's worth considering."
Can chimpanzee spirituality be productively explored outside the realm of science? As I told Paulson on the air, an insistence on delving into chimpanzees and the sacred, in my view, says a lot more about us than it does about chimpanzees.
Barbara J. King is an anthropology professor emerita at the College of William and Mary. She often writes about the cognition, emotion and welfare of animals, and about biological anthropology, human evolution and gender issues. Barbara's new book is Personalities on the Plate: The Lives and Minds of Animals We Eat. You can keep up with what she is thinking on Twitter: @bjkingape