When we look at ourselves next to our closest evolutionary cousins — the chimpanzees, with whom we humans share some 99 percent of our DNA — what strikes us most are the enormous differences. Above all, we tend to celebrate the superiority of our minds, which are capable of discovering the Pythagorean theorem, building a spaceship, and painting the Mona Lisa; our minds are what take us out of the animal world and into the world of culture and history. But the contributors to The Primate Mind, a new collection that showcases cutting-edge thinking about primate psychology and neurology, urge us to put aside the differences for a moment, and think instead about the similarities. As primates, our brains share deep structures with those of chimps and baboons; if you go even further back on the evolutionary tree, we have things in common with dogs and birds. Do these animals, too, have minds in any meaningful sense? And if so, how would we know it?
These are the questions addressed by most of the contributions to The Primate Mind, which range from fairly accessible, wide-ranging essays to technical descriptions of experiments. They share what Frans de Waal and Pier Francesco Ferrari, the volume’s editors, call “a bottom-up approach to the primate mind.” Rather than focus on what separates humans from “lower” species of primates, or try to make primates do human tasks — such as gorillas painting pictures or learning language — these scientists ask what basic mental structures all primates share.
The answer turns out to be surprising: all primates, and many more primitive animals, are capable of empathy, cooperation, learning, and deduction. Take an experiment described by Ludwig Huber, in his paper “What, Whom, and How: Selectivity in Social Learning.” Six species — marmosets, ravens, jackdaws, dogs, keas, and human children — were shown members of the same species searching for hidden food. It turns out that keas and marmosets are almost as good as humans at observing the search and figuring out how to replicate it. And there is reason to think that such animals are not simply copying the actions they see but actually thinking in goal-oriented terms. This is suggested by another experiment involving dogs: dogs who watched a dog use his paw to push a lever for food preferred to use their own mouths to push a similar lever, suggesting that they were not following blindly but understood the logic of the process.
The central concern of The Primate Mind, however, is empathy. Can we say that chimps truly enter into one another’s point of view, the way humans do? Here the exciting development has to do with the discovery of “mirror neurons” in the primate brain. These neurons are activated when an individual watches another individual perform an action or display an emotion, thus replicating the experience in its own brain. “Mirror neurons,” writes Marco Iacoboni, “gracefully solve the problem of other minds, which is fundamentally a problem of having access to the mind of other people.” Even for non-specialists, The Primate Mind offers the excitement of seeing science begin to offer concrete answers to such fundamental and ancient human questions.
Scott Hubbard is NASA’s “Mars Czar,” in charge of a series of spectacular scientific missions to the Red Planet over the last decade. In Exploring Mars: Chronicles from a Decade of Discovery, Hubbard explains what we have learned about our nearest neighbor in space, including the possibility that Mars harbors water and even traces of life.
Who decided that boys should wear blue and girls should wear pink? Cultural historian Jo Paletti solves the mystery in Pink and Blue: Telling the Boys from the Girls in America, using catalogues, dolls, and vintage clothes to show how children’s dress became gendered in the twentieth century.
The last hundred years were also The Ellington Century, argues David Schiff in a new study of Duke Ellington’s music, using his jazz compositions to help explore the evolution of modern classical and popular music.