Frans de Waal showed non-human species are more complex than they are given credit for: Anindya Sinha
Anindya Sinha. Photo Credit: M D Madhusudan
Frans de Waal, a towering figure in the field of primatology, died on March 14, 2024 in Stone Mountain, Georgia, United States. He was 75.
For several decades, the Dutch-American scientist strode like a colossus in the discipline. He was the Charles Howard Candler Professor of Primate Behavior in the Department of Psychology at Emory University in Atlanta, Georgia.
De Waal was also director of the Living Links Center at the Yerkes National Primate Research Center at Emory. He authored several books like Our Inner Ape (2005).
De Waal famously explored empathy and emotion in bonobos and chimps.
Down To Earth spoke to Anindya Sinha, one of India’s leading primatologists about the legacy of de Waal.
Sinha, professor at the National Institute of Advanced Studies, located on the Indian Institute of Science campus in Bengaluru, is known for his scientific reporting of the Arunachal macaque Macaca munzala, a species new to science and his work on cognition and consciousness among wild bonnet macaques M. radiata.
He shared his insights into the life and work of de Waal, with whom he had interacted, offering a critical appraisal of the late scientist. Edited excerpts:
Rajat Ghai (RG): Did you meet Frans de Waal in person? What were your impressions about him as an academic, as a primatologist and as a person?
Anindya Sinha (AS): Yes. I had met Frans twice — in a conference and once during a visit to the Yerkes National Primate Research Center, associated with Emory University in Atlanta, US. The city in the state of Georgia is where he spent a significant part of his academic career and also his last days, before unfortunately passing away recently.
We had very long discussions — about his work and mine. He was very interested in my work on macaques, species of monkeys that he was deeply interested in as well.
Frans’ work was largely on the great apes. In his work, Peacemaking among Primates (1990), he does talk about reconciliation, even in macaques.
But by and large, his main paradigm was that humans have shared far more evolutionarily with the great apes than we have given them credit for. This includes empathy, sympathy, compassion and reconciliation after conflict.
Frans always believed that these characteristics evolved in the common ancestors of both present-day great apes and modern humans and from whom we have inherited these.
Our own studies, however, suggest that monkeys may have already evolved simple forms of these traits, but not to the extent that we see in the great apes or humans.
As an individual, Frans was a lone crusader. I think he really changed the way we look at our evolutionary roots. He talked about morality, ethics and the various behavioural traits that contribute to these conceptions.
He struck a lonely path in the sense that not too many of us have examined these issues in non-human animals. While some of us agreed with him, others had reservations about what he said. But the fact remains that he was an uncompromising individual. He struck to his beliefs and there were no two ways about it.
RG: Was de Waal’s focus too much on great apes, compared to monkeys? Was that unfair in a way, given that the former are restricted to a few geographies whereas the latter share habitats with humans worldwide?
AS: The monkeys, including the macaques, with whom we are very familiar — as there are about 10 species in our country — are the most diverse of all primate genera. The macaques are second only to humans in distribution and are evolutionarily, extremely important species in their own right.
Academically, a criticism that I have had of Frans’ work is not that he did not necessarily look at macaques or other simian species but rather, somehow intellectually, he did not perhaps consider them worth examining from the perspectives of some of the qualities of great apes and humans that he admired.
He did conduct studies of simians but these were all done on one or two groups of each species in captivity. In fact, Frans was heavily criticised and continues to be so because his initial stance allowed him to explore the lives of the great apes and monkeys in captivity and in ways which may not perhaps be considered ethical today.
His work on macaques — especially the rhesus — came in for criticism because he allowed for certain experiments to be conducted. He supported them at the time but never did so again as at some point he may have felt that these experiments were unethical, as was his support for them. However, he never seemed to talk too much on these issues.
There have been other primatologists like Hans Kummer — a forgotten genius in my opinion — who, in his last days, regretted some of the work on wild primates that he had done. I have always admired such scientific and academic honesty in researchers.
But coming back to de Waal, I really wish he had looked much more at the simians. He restricted his ideas of how these complex traits of sympathy, empathy and compassion were only shared by great apes and humans.
Our own work on macaques, however, reveal that they may possess the ability to develop belief systems and form mental representations, generated by direct personal experience. This suggests a rather early evolutionary origin for fairly sophisticated cognitive capabilities, characterised by an objectified sense of the self with limited regulatory control over more subjective levels of self-awareness, in macaques, pre-dating those of the great apes.
The late Frans de Waal. Photo credit: Frans de Waal Facebook Page
How much of these behavioural processes could be attributed to emotion —which Frans hypothesised for the great apes — in macaques, however, remains an open question, also because it is very difficult to scientifically define emotions in other beings, who cannot communicate with us. But all of these remain neglected in Frans’ work.
In fact, some of the macaque species have very complex socialities, possibly comparable to chimpanzees in certain ways. If one is interested in the evolution of social intelligence and complex cognitive capacities, therefore, simians, especially macaques, really need to be studied, as has been recognised by several authors.
There is also the application of our understanding of macaque sociality, cognition and decision-making processes in our everyday relationship with them, as you point out.
How do we govern our relationships with them? Does Frans’ work on the great apes have implications for what we should now investigate in the macaques so that our everyday relationship with them can also be shaped by our understanding of their complex socialities and cognitive abilities?
RG: Would it be fair to say this bias towards great apes persists in primatology as a discipline?
AS: Yes, you are right. When primatologists in the West — the United States and western Europe — came down to tropical primate regions in Africa and Asia, they were limited in the amount of time and resources that they had for such studies.
This is why the more complex aspects of primate lives — which need long-term engagement not only with groups but also with identified individuals — largely remained out of bounds of these Western primatologists.
Again, I would not say it is only logistics. Primatological thinking, like its zoological counterpart, had never bothered about individuals. Species — or at the most, populations — were the focus. What we really now need to understand are particular groups or individuals, in fact, concentrate strongly on their individuality.
We are now beginning to recognise that individuality is very important across non-human primates. Frans’ own work talked about particular chimpanzees, rather than species or groups. Why have we not done so for the macaques?
Indian primatologists, I believe, should follow Frans as an inspiration and examine, in our own species, the complex behavioural traits and conceptualisations, the evolutionary roots of ethics and morality, the beginnings of which may have already begun in the simians before the great apes. But we have never studied monkeys enough to know if this is indeed true.
We should also remember that most studies on individual primates by Western primatologists have been conducted in captivity. And so, people like Frans or Bernard Theirry have completely hypothesised models of sociality and social cognition, based on a few captive primate groups.
But captivity completely changes the lives of these complex beings, who are typically under stress. Moreover, only two or three groups of each species have been studied in this way. Is it possible to generalise these findings across species? I personally do not believe so.
I would put this forward as a very strong critique of much of Western primatology, especially with regard to cognition and other complex behavioural profiles that Frans and other researchers have always discussed and hypothesised about.
RG: Does this apply to all simian groups?
AS: In principle, yes. However, we must distinguish between two lines of simian evolution. The first is that of the leaf-eating or colobine monkeys, like the langurs of south and southeast Asia or the colobus monkeys of Africa.
Interestingly, colobine behavioural specialisations largely seems to be of a more ecological nature. Being primarily leaf-eaters, they need to exercise a tremendous amount of choice in the kinds of plant materials they feed on or the way they process such materials.
Their cognitive abilities in this regard are fascinating. This could potentially even include, it is believed, self-medication and other such behavioural traits.
An interesting example is that of the gorilla. The largest primate on Earth, gorillas are characterised by rather simple societies.
On the other hand, Richard Byrne of St Andrews University in Scotland and his colleagues have showed a bewildering variety of ways in which gorillas process their food. This is cognitively unparalleled among primates.
The second line of evolution among simians is that of the omnivorous cercopithecine species, including the macaques of south and southeast Asia, and the mangabeys, mandrills, drills and baboons of Africa.
These species are more characterised by their large groups and social complexity, which may have evolved because they are largely generalists in terms of their omnivorous diets. The rhesus and bonnet macaques of northern and southern India have numerous sources of food, which do not require much processing or handling time.
Can you, however, imagine the social complexity in individual relationships in such large groups as, for example, in that close to 150 stump-tailed macaques in the Hollongapar Gibbon Sanctuary of Assam? This is possible because they have abundant food and yet, we know so little about their social cognitive abilities to maintain such large groups.
We therefore need to follow Frans’s footsteps and study much more closely the macaques and other simians of southern Asia, which are fast disappearing, given the enormous conservation threats that they and their habitats are currently facing in the Anthropocene.
RG: What would be de Waal’s everlasting legacy?
AS: Frans’ work, I would advocate, is reminiscent, in a way, of the great tradition of Jane Goodall and her like. Both brought the great apes to us in ways that allowed us to identify with them and question what it is that made us uniquely human.
Jane shook up the world when she showed chimpanzees fishing for termites and their groups doing so in different ways, hinting, for the first time, at cultures and behavioural traditions among the great apes, not entirely unlike that of ours.
Previously, tool use and their making, the cognitive mechanisms underlying them, and the establishment of cultures was considered the exclusive preserve of humans.
Goodall made us question the very definition of being human. Instead of marvelling at her work and accepting it gracefully, however, we began to think about other definitions that would continue to prove that humans were uniquely superior to all other non-human beings, something that is academically indefensible and scientifically unethical.
I therefore consider Frans to be in that tradition, which showed us, once again for the first time, that principles and practices of morality and ethics, hitherto considered uniquely human, were not, in any way, limited to us alone.
Having said this, a fundamental criticism of Frans’ work that I would like to put forward is that many of the terms he used cannot scientifically either be defined or defended as valid categories.
Yes, great apes possibly have emotions. But how do you define these emotions objectively and even more importantly, how do you detect their presence in non-verbalising beings? Would you, for example, know what emotions I am experiencing or if there are any emotions at all in me if I had tears streaming down my cheeks but could not speak to you?
Frans has thus told us that we have evolved traits which we share with other species like the great apes. They may indeed have complex codes of conduct, the behavioural manifestations and ways of expression of which we may think could be defined as being similar to human morality or ethics.
But can we assume that chimpanzees are indeed moral beings or believe in such codes of conduct? I am not sure at all about this and moreover, why then cannot the behavioural codes of conduct of macaques be defined as constitutive of their own unique sense of morality?
But the point remains that we must respect other beings for being far more complex than we have given them credit for, for being unique in their own ways. And Frans de Waal has been instrumental in pointing this out to us in his own unique ways.