Emiliano Bruner, paleoneurobiologist: ‘With this big brain, we are intelligent and sad monkeys’

Evolution is only interested in one thing: procreating and perpetuating the species, says paleoneurobiologist Emiliano Bruner. Nothing more. It does not care about our suffering or our emotional discomfort, only about our reproduction: “Evolution does not care about our well-being, but rather our evolutionary success,” the scientist concludes. And, depending on how you look at it, the journey of Homo sapiens — which now have eight billion individuals on the planet — is an evolutionary success. As long as it is compared, of course, with other hominids. Because if you are looking at cockroaches, for example, which have been on Earth longer and have an infinitely greater capacity to spread, what modern humans have achieved is a trifle. It is all a question of perspective.

Bruner works with ancient and modern human brains. Although he began studying spiders and beetles during his biology degree, he made the leap to humans three decades ago with a PhD in paleoanthropology, studying the evolution of the species by analyzing and reconstructing the internal cavity of the skull in ancient fossils. He then moved to cognitive archaeology, examining the behavior of extinct hominids through their traces in the environment.

The scientist — who works as a paleobiologist at the National Museum of Natural Sciences in Spain — spoke to EL PAÍS after giving a lecture in Barcelona as part of a conference held by the Obesity and Bariatric Surgery Unit at the Hospital del Mar. Bruener — who is an expert in visuospatial integration, i.e. how the brain receives and processes visual and somatic information — warns that humans have a brain that is three times larger than what a primate of our size should have. He suggests that perhaps “the structure is not prepared for so much power,” explaining in his talk that the brain “thinks a lot and the body suffers because it is not prepared for an engine that forces so much.” He goes into more detail with EL PAÍS.

Question. You have studied the brain anatomy and behavior of the species that preceded us. How have we changed?

Answer. Evolution used to be seen as a linear and progressive process. So, if we are the last, either you are like me or you are worse than me. And that’s not the case. You have to understand that evolution is not gradual or progressive: there are different lineages and each one evolves its own independent traits. Imagine, for example, us, Homo sapiens; the Neanderthals, who are extinct cousins; and the chimpanzees, who are current cousins. Well, these three stories have had different paths. Each one has changed, depending partly on chance and partly on the contingent situation in which they found themselves. It is impossible to think that the chimpanzee is a primitive human or that the Neanderthal is a less evolved Homo sapiens. Each one has evolved its own capacities and its own traits, both anatomical and cognitive. Thus, we have to assume that Neanderthals or chimpanzees may have had or have cognitive abilities that we have either lost or never even evolved.

Q. For example?

A. Neanderthals had a brain that was the same size as ours. It is true that the parietal lobes were less complex, so it is true that their visuospatial and attentional capacity was less specialized. But, then, that engine was full of other things: they may have had different cognitive abilities from us, a different way of thinking. We have invested in attention, mental imagination and language, on that triad we base our ability to think. It is possible that Neanderthals made another choice that we obviously do not know.

Q. You suggest that “excessive mind wandering between past and future has created the pandemic of stress and depression.” If Neanderthals did not develop our capacity for attention, were they more of a carpe diem kind of person?

A. Absolutely. My bet is that they had a more holistic-intuitive way of reasoning, that is, intuition linked with the present moment and perceptual response. They may have invested more in this and we, more in a conceptual approach. If this hypothesis is true, they suffered much less from all the ruminations, problems, frustration and psychological stress. You can’t say that they were more attentive, more carpe diem or more mindful, because they probably didn’t do it intentionally.

Q. But the Neanderthals went extinct and we did not. Doesn’t that put us in a certain degree of superiority?

A. Homo sapiens are probably 200,000 years old. Homo erectus, a hominid with a 1,000 cubic centimeter brain [Homo sapiens has, on average, more than 1,300 cubic centimeters] and extremely basic, naive, and simple technology, lasted almost two million years. So if we’re going to measure evolutionary success, we’re nothing compared to Homo erectus. Let alone cockroaches or sharks or turtles.

Why did the Neanderthals become extinct? We don’t know. The first possibility is that Homo sapiens are violent and slaughtered and preyed on the other species, but there is no evidence for this. The second possibility is that we started competing for the same resources — we were all hunter-gatherers — and we did better and took their sandwich, and they became extinct because they were not ecologically competitive with this new species. The third possibility is that, as is always the case in evolution, the Neanderthals became extinct on their own and Homo sapiens simply colonized lands that were becoming empty.

Q. In an interview in Jot Down magazine, you said that humans have evolved “superpowers,” but without an instruction manual, these powers could backfire. Does great power come with great responsibility?

A. In all mythologies, humans are given a superpower that makes them special. But often the superpower gets out of hand, and we end up shooting ourselves in the foot. And this is probably what happens with our capacity for mental projection. We are so good at projecting into the past and the future that we start to create worlds that do not exist and, finally, the present becomes small, while the past and future become gigantic. And this past and future begin to be tinged with insecurity, fear, uncertainty, sadness, melancholy and this crushes our present and, above all, crushes our capacity for psychological response.

Q. Would that explain the global rise of emotional distress that some scientists have warned of?

A. In my opinion, if the problem is due to our ability to project — the relationship between attention, mental imagination and language — it is pandemic, regardless of your culture. And it’s not something that’s happened today, but we don’t know when Homo sapiens evolved this way of suffering. We began to find the modern brain around 80,000 years ago, long after the origin of Homo sapiens, which is around 200,000 years ago. If this hypothesis is true, this is when suffering was established, this ability to never be in the present because you are always in the past and in the future. It is a superpower, because it allows you to develop a super complex technology and society, but it creates constant psychological stress throughout your life.

Q. Can this superpower end up unbalancing us?

A. It depends. Evolution is doing great, because it only wants you to reproduce, and there is only one species that has a worldwide distribution and has eight billion individuals. This is a total success, no primate has done better, although, compared to cockroaches, we are terrible. How about in terms of quality of life? Very bad, but evolution is not interested in that, it is the individual that has to have a say and decide what is most important.

Q. In your talk, you mentioned the existence of evolutionary imbalances. Are pathologies such as obesity the result of an evolutionary imbalance? Has our social context, such as the way we eat or our access to food, evolved faster than our brain to adapt to the amount of food it needs?

A. In the case of obesity, it is very clear it is a case of evolutionary imbalance. You were programmed for a certain type of environment and this environment has changed too quickly and your programming clashes tremendously with your evolutionary environment. All this anxiety, stress or, simply, a search for pleasure, was also triggered by food before, but with food that was what a hunter-gatherer could get. We have been hunter-gatherers for 200,000 years, farmers for 10,000 years and supermarket customers for the last 50 years. We are not programmed to have all this at hand and, what’s more, in a society economically based on the incentive to consume and eat. You had been programmed to vent your anxiety for food, but in a situation where there was no food, so it was a harmless programming.

Q. Are there more evolutionary imbalances?

A. A hundred. For example, the musculoskeletal and locomotor systems. We are programmed to be hunter-gatherers, not to sit 14 hours a day. Our body, our metabolic, physiological and anatomical system, was programmed by hunter-gatherers to run, not to sit still in a chair.

Q. What is your greatest concern about our species?

A. With this big brain, what makes us human is that we are intelligent and sad monkeys. My hope is that one day we can overcome this condition. My biggest fear is that this condition is so natural, we will never overcome it.

Sign up for our weekly newsletter to get more English-language news coverage from EL PAÍS USA Edition