Raven (Corvus corks) in Southern California. Photo: Ingrid Tyler / Flickr, CC BY-NC 2.0.
Some time ago, I read a great book with a provocative title: Are we smart enough to know how smart animals are? Probably not, says the author – Frans de Val, a well-known Dutch-American primatologist. I agree, but I think we should keep trying. After all, human intelligence is largely due to trial and error.
The inability to know how smart animals are can be a serious professional handicap for those of us who study animals and build theories to explain their behavior. Our theories can be far from a sign if our intelligence limits our belonging to animal intelligence. But hopefully there are some (insufficient, I worry) maverick scientists brave enough to continue pushing the boundaries of their imagination.
The main evolutionary paradox concerns why animals are beautiful to each other. Many of my fellow humanists think that we scientists are corrupt to think so. What they do not understand is that our best theories have difficulty adapting to beauty. We love beautiful things for sure, but that is not enough. Our understanding of animals from the first principles and our mathematics of what evolution should make them do should predict beauty – but they often do not.
You might say that the problem is in our theories. You are right, of course, but how do we make our theories consistent with evolutionary logic on the one hand and the awakened beauties of the animal kingdom on the other?
Enter the # 1 scientist, Johnon Bourdon Sanderson Haldan (1892-1964). In the words of his student Johnon Maynard Smith:
„[Though] Haldan will be remembered for his contributions to the theory of evolution difficult to classify. A liberal individualist, he was best known as a leading communist and contributor to a weekly article in the Daily Worker. A double first class in Oxford classics and mathematics, he made his name in biochemistry and genetics. “The captain of the Black Watch, who admitted that he enjoyed World War I more, spent the rest of his life in India writing in defense of non-violence.”
Haldan (c. 1953) is thought to have said: “If one or two of my brothers drowned in a river, I might not have risked my life to save them, but if more than two of my brothers drowned, I might try to save them. put them at risk for my life, ”or something close to him. This ridicule is at the heart of modern gender selection theory. But if Haldan was maverick enough to think of it, he was also maverick enough to leave it – no more than one subject.
Enter the scholar # 2, William Donald Hamilton (1936-2000), who wrote an essay entitled “My Intentional Funeral and Why,” in which he said:
“I will leave a sum in the last will for my body to be transferred to Brazil and these forests. It will be placed in a way safe from possums and vultures, just as we make our chickens safe; and this is great Coprophane a beetle will bury me. They will come in, bury me, live according to my body; and in the form of their children and mine, I will escape death… And finally I too will shine like a purple beetle under a stone ”.
And then he went on an expedition (which some would say was stupid) to the Democratic Republic of the Congo, looking for evidence of the origins of AIDS, and died of complications from cerebral malaria he contracted there.
But before all this, he developed the idea in 1964 – probably conceived largely independently of Haldan – that being handsome, even altruistic, to close genetic relatives could reconcile with Charles Darwin’s theory of natural selection. Today, we recognize that this is perhaps the most significant modification of Darwin’s theory of natural selection to date, and we mark it as Hamilton’s rule. And since then we have discovered that most organisms – bacteria, plants, insects, worms, fish, frogs, lizards, birds and mammals, and many others – have developed clever ways of saying who their relatives are.
But the problem is that animals are often nice to non-relatives, and that means disobeying Hamilton’s rules.
Enter scientist # 3, Robert Travers. Travers is an American scientist who has been described as “arguably the most original thinker of today in evolutionary theory.” In 1974, Travers proposed the theory of “reciprocal altruism,” a simple idea that no act of helping or altruism is evolutionarily harmful to the actor until it is reversed in the future.
Theorists have since conceived of different types of reciprocity: direct reciprocity (“I will help you because you have helped me in the past”), indirect reciprocity (“I will help you because I saw you help someone else”), and generalized reciprocity. “I’m helping you because I generally feel good that someone helped me.”
Unfortunately, the idea of reciprocal altruism as a solution to the paradox of altruism towards foreigners has been gathering dust for a long time. Why? Because most people were not smart enough to think that animals – let alone bacteria and plants – could be smart enough to keep track of who helped whom, when and how much, and to determine how much return aid is now commensurate with the good deeds of the past.
I am happy to say that over the last few decades, we have gradually become smart enough to know how smart animals are.
In 1984, erarald S. Wilkinson, then at the University of California, San Diego, gave the first clear example of direct reciprocity in the context of sharing food between vampire bats (Desmodus rotundus) studied in Costa Rica. These bats live together in small groups of 8-11 people, until they are 2-11 years old. They go out every night to drink the blood of cattle and horses. If they are lucky, they can inject an amount of blood equal to their body weight. But some are always unlucky and return on an empty stomach.
Those who do not eat for three consecutive nights will die, which implies that those who had a good meal today have reserves worth three days and, therefore, something to spare. Bats clean each other’s bellies, making it difficult for well-fed bats to bluff. Thus, they have all the appropriate conditions for the evolution of reciprocal altruism. But do they have the cognitive ability to perform honest transactions?
Using field and laboratory experiments, Wilkinson showed that vampire bats met all three necessary conditions for reciprocal altruism. They had (1) repeated blood exchange interactions with the same individuals; (2) the benefits of donating blood outweighed the costs; and (3) most importantly, they recognized those who had donated blood in the past and preferred to donate blood, regardless of kinship, and refused to donate to those who had been rejected in the past. His student, Erarald Carter, currently at Ohio State University at Columbus, has since confirmed this result with larger samples and more rigorous experiments.
Indirect reciprocity requires animals to be accountable for what others do to them, as well as the result of what others do to others. This seems to be even further than expected from animals. And yet, some people were brave enough to look for it and found that it was not entirely beyond the ability of some animals.
In the tropics, many large fish have their own, including the inside of the mouth, cleaned of smaller fish, which feed on dead skin and ectoparasites. This relationship between the cleaner and the client is delicate. Both sides can betray: cleaners can bite healthy tissue and clients hug cleaning agents, but they usually trust each other. Depending on the relative levels of supply and demand, there may be a long line of customers waiting for the cleaning service or a long line of cleaners waiting for work. This provides opportunities, especially for those waiting, to awaken and evaluate the results of others.
Redouane Bshari of the University of Neuchчеtel in Switzerland and Alexandra S. Grutter of the University of Queensland, Australia, have teamed up to show that customers care about the work ethic of different cleaners and prefer to service more honest ones. Cleaners can also eavesdrop on customers, assessing their propensity to be careful and stay honest while cleaning those customers who tend to eavesdrop on cleaners at work.
Generalized reciprocity requires animals not only to feel good when someone helps them, but also to have a desire to be nice to strangers in such moments. Instead of dismissing this as too anthropomorphic, Claudia Rutte and Michael Taborski of the University of Bern put theory to the test. They trained Norwegian rats (Rattus norvegicus) in the lab to pull a stick to produce food for another rat, even though they got nothing for themselves. Using this experimental setting, they showed that rats were more likely to help unknown rats if they had previously been helped by other unknown rats.
Therefore, animals seem to be smart enough to show direct, indirect, and generalized reciprocity. With this knowledge, scientists have become motivated to explore the frontiers of knowledge and memory of animals with newly discovered enthusiasm and confidence. Some really cool and fun experiments are now being done with corvidas (birds from the crow family).
A research group in Austria is experimenting with ravens (Corvus corks) in large housings. A trainer gives a raven a piece of bread, but ravens are better than a piece of cheese. Another experimenter offers a piece of cheese in exchange for a piece of bread. Ravens love this and immediately jump at the good Samaritan experimenter and exchange their bread for cheese. But some experimenters are “unfair”: they accept the bread and in full, given the raven they are waiting for, they eat the cheese themselves. Ravens remember the identities of “fair” and “unfair” human experimenters for up to a month, even after a single interaction. Then they avoid “unfair” experimenters and prefer to bring bread to “fair” experimenters.
A new way of thinking among scientists, open to the possibility of knowing animals beyond our expectations and perhaps beyond our own capabilities, has created new hope for understanding the logic of animal behavior. I think it is fair to say that animals do not make us smart! But we also need to adapt our education system and our social norms to create and tolerate more fraud.
Ragavendra Gadagar is Professor in the Department of Science and Technology (VCT) Year of Science, Professor at the Center for Environmental Sciences at the Indian Institute of Science, Bengaluru.