Compared to other animals, humans have built highly developed societies in terms of culture and technology. Historically this has been attributed to a hierarchical superiority of humans on a supposed evolutionary scale. For example, theories that claim that the human brain is larger or simply superior are still in vogue today.

The research and theory of Michael Tomasello have been the most relevant recent contributions of Comparative Psychology to a classic question: what makes us human? That is, what makes us different from other animals?

Michael Tomasello’s theory

Michael Tomasello, co-director of the Max Planck Institute for Evolutionary Anthropology, is a psychologist who researches social cognition, that is, the way in which people process social information, social learning and communication.

Tomasello, whose perspective is situated in constructivism, states that we humans differentiate ourselves from other species by our capacity to collaborate in activities when we share goals . Tomasello calls this “shared intentionality”.

Comparative studies with children and chimpanzees

In recent years, Tomasello has studied communication and shared intentionality in particular. To do this he compared the cognitive processes of children and chimpanzees , as they are the animals closest to humans.

In his experiments, Tomasello analyzed, among other aspects, how children and chimpanzees share the rewards after a collaborative effort. To do this, he compared the results obtained in collaborative tasks carried out by pairs of children or chimpanzees.

Although the chimpanzees studied were capable of working as a team, after achieving the reward, food in this case, the most dominant of the two kept the entire prize. This tendency to individualism makes it difficult for non-human primates to maintain cooperative relationships in a sustained way over time.

On the other hand the children shared the reward more or less fairly after collaborating to obtain it. Even if before they discussed or tried to keep all the food, there was a kind of negotiation that concluded, normally, with each of the children keeping half of the prize.

In another of the experiments, one of the partners got the prize before the other. In the case of the children, the first one to get the reward continued to collaborate with the other one until the latter got his too. On the contrary, the chimpanzee who got the food first did not care about his partner.

Differences between human and chimpanzee societies

Tomasello states from his experiments and observations that societies formed by great apes are much more individualistic than those of humans. He attributes this to the greater ability of people, even when they are very young, to collaborate and to attribute intentions to others.

This ability to “read the mind”, or imagine the emotions and thoughts of others and understand that they may be different from one’s own, is known as “theory of mind”. Great apes and other animals, such as crows or parrots, are also considered to possess this ability, but it is much less developed than in humans.

Tomasello claims that great apes often use the theory of mind to compete, for example to get sexual partners. They may also engage in altruistic or prosocial behavior to help other individuals, but they usually do so only if there is no competition for resources and minimal effort.

According to Tomasello, groups of chimpanzees are largely based on dominance and individual activity ; for example, food collection or care of offspring is carried out by a single individual.

In contrast, among humans, social relations and hierarchies are not determined only by selfishness and domination, but collaboration is more important. Tomasello argues that non-cooperative people (the parasites or “free riders”) tend to be left out of cooperative activities.

The development of culture and morality

Another fundamental difference between us and other primates is that humans create social norms and institutions . According to Tomasello, these are a consequence of our capacity to exchange information with other members of our group and to transmit culture from generation to generation, which allows us to progressively make our societies more complex.

The degree of collaboration and interdependence also increases as societies develop. Human groups tend to become larger and larger: in a few thousand years, a tiny period of time in the context of evolution, we have gone from being part of small hunter-gatherer tribes to today’s globalized world. This progress would have been unthinkable without the development of language and the cumulative progress of culture and technology.

According to Tomasello children are instinctively cooperative but as they grow up and are influenced by the surrounding culture they learn to discriminate with whom they collaborate, mainly so as not to be exploited by “free riders”.

Human children internalize the norms built by their society to such an extent that they bestow upon themselves the responsibility to make others comply with them, even if the opposite does not harm anyone. Tomasello argues that human culture encourages us to do things “the right way”, that is, the way most of the group we are part of does, and that those who do not comply with social norms get a bad reputation and are viewed with suspicion.

Human and animal intelligence

Historically, human intelligence has been considered quantitatively superior to animal intelligence because our brain is more developed. However, according to Tomasello’s studies children surpass chimpanzees in social intelligence but have a level of physical intelligence, for example spatial or corporal, equivalent to that of chimpanzees.

Tomasello and other authors have proven that great apes have cognitive abilities that until recently we would have attributed exclusively to humans. Among other things, they know that objects continue to exist even if they disappear from view (the Piagetian object permanence) and can differentiate quantities mentally.

Baby chimpanzees are also skilled at communicative gestures, but their variety and complexity are rare. Another ape, the Koko gorilla has been trained in the use of sign language by Francine Patterson. Koko has even been able to create complex concepts by combining several words. There are also examples of how non-human animals can pass on culture from generation to generation: for example, a group of chimpanzees in Côte d’Ivoire are taught to use stones as hammers to open nuts.

Cooperation makes us human

According to the constructivist Tomasello, people learn language through cumulative cultural transmission, which has made our verbal communication very complex. Furthermore our body is perfectly adapted to language , from the phonatory organs to specific areas of the brain. Just as marine animals have adapted to an aquatic context, we have adapted to a social context.

Humans need culture to develop. Without social interaction and language, not only would we not reach our full potential as a species, but our cognitive and social abilities would be very similar to those of other primates. Wild children, like Victor de Aveyron, serve as an example of this: without contact with other people, we humans lose what makes us special .

Bibliographic references:

  • Herrmann, E.; Call, J.; Hernández-Lloreda, M. V.; Hare, B. &Tomasello, M. (2007). “Humans Have Evolved Specialized Skills of Social Cognition: The Cultural Intelligence Hypothesis”. Science, 317 (5843): 1360-1366.
  • Tomasello, M.; Carpenter, M.; Call, J.; Behne, T. & Moll, H. (2005). “Understanding and sharing intentions: The origins of cultural cognition. Behavioral and Brain Sciences, 28 : 675-735.
  • Warneken, F.; Hare, B.; Melis, A. P.; Hanus, D. & Tomasello, M. (2007). “Spontaneous Altruism by Chimpanzees and Young Children”. PLoS Biology, 5 : 1414-1420.