Are we really different from animals?

Our brains represent about 2% of our overall body mass

CNN News Wire | 11/21/2013, 2:03 p.m.
Chimpanzees from the former Coulston Foundation in Alamogordo, New Mexico were moved to Save the Chimps sanctuary in Ft. Pierce Florida.

So what are the differences that enabled us to dominate the planet?

In my book, I examine the most common proposals about what sets us fundamentally apart from the rest: language, foresight, mind-reading, intelligence, culture and morality.

On inspection it becomes clear that various animals, in particular our closest animal relatives, the great apes, have some sophisticated capacities in even these domains. Nonetheless, the human ability in each of these contexts is special in certain respects. Two characteristics in particular keep re-emerging as critical: our deep-seated drive to exchange our thoughts, and our ability to think about alternative situations and embed them into larger narratives.

Humans rely on a uniquely flexible, but also risky, way to control behavior through clever thinking. We can travel mentally in time and consider how events unfolded or what the future might hold. We can compare alternative routes to the future and deliberately select one plan over another — giving us a sense of free will and an edge over creatures with less foresight.

This also burdens us, however, with the responsibility for getting it right. The future is uncertain and, of course, we often get it wrong.

The key to making this a successful strategy has been our fundamental urge to link our minds together, to look to one another for useful information. We ask questions and give advice. We bond through sharing experiences. We can use our imagination to entertain the perspectives of others as well as to consider entirely fictional scenarios.

This allows us to take advantage of others’ experiences, reflections and imaginings to prudently guide our own behavior.

These two attributes appear to have been essential to our ancestors’ transforming common animal traits into distinctly human ones — communication into open-ended language, memory into strategic planning and social traditions into cumulative culture. Our extraordinary powers do not derive from our muscles and bones, but from our collective wit. Together, our minds have spawned civilizations and technologies through which we have changed the face of the Earth, while even our closest animal relatives live quietly in their dwindling forests.

Why only us?

If these traits are so useful, you may rightly wonder why other creatures did not evolve them, too. As it turns out, other creatures did — but they have gone extinct. The gap between humans and other creatures on this planet previously was not as vast as it is today.

Chimpanzees and other apes have not always been our closest living relatives. Some 40,000 years ago, we still shared this planet with several smart, upright-walking, stone tool-carrying cousins, including Neanderthals, Denisovans and the “Hobbits” of Flores.

Go back further to around 2 million years ago and there were three distinct genera of hominins (Australopithecus, Homo, and Paranthropus), each likely comprising several species. Though there are debates about how many species need to be distinguished, it is clear that for much of our past our ancestors were but one of a group of diverse hominins.

A gap is defined by both its sides: We appear so different from other animals because all our closest relatives have become extinct. And our ancestors may well have contributed to their fate.

Note that all our closest animal relatives today, the apes, are endangered because of human activity. They may eventually join Neanderthals and Paranthropus as half-forgotten creatures of the past. And so, if we do not manage to stop this from happening, our descendants may be even more baffled by their own apparent uniqueness.

Thomas Suddendorf | CNN