The physical signature of human happiness is the D smile. The D smile did not originate in contexts that we today think are fast tracks to happiness. The D smile did not originate in experiences of sensory pleasure—Cro-Magnon individuals savoring fresh meat or the ripest of berries. It did not originate in contexts where our hominid predecessors enjoyed shifts upward in social status. The first D smile did not originate in contexts in which one individual enjoyed the accumulation of important resources. In fact, Christopher Boehm has summarized studies of hunter-gatherer hierarchies, and found that they systematically downplay any sudden abundance in resources through modesty and generosity.
In our primate evolution, the D smile was the first vocabulary of friendly intent and affection, in particular between near-equals. High jen ratios and the roots of human happiness are found in those moments when individuals moved toward one another toward cooperative and intimate ends. Our ultrasociality required this, as well as an all-purpose signal of cooperative intent, one that is highly visible and unambiguous, and one that could preempt conflict and spread cooperative relations potently and quickly, faster than a stranger could cock his arm and throw the first punch. Evolution’s answer to the question of how to most powerfully communicate our capacity for jen was like that of the classical Greeks: the smile.
7Laughter
IN THE 1982 FILMQuest for Fire, three hapless Neanderthal males leave their marsh-dwelling tribe in search of fire—the source of their haphazard provision of food and the hierarchical organization of their group. During their quest the three travelers escape from saber-toothed tigers, encounter towering woolly mammoths, and scare off a potential attack from a small tribe of paunchy, red-haired Neanderthals. In this last escapade, they rescue a different kind of early human. She is a more evolved female Homo habilis, finer in bone structure and facial morphology, lacking the carpet of hair covering the body, and adorned in patterned, tribal paints.
This female leads the three males on a primordial Jules and Jim road trip to her village. In this adventure, several distinctions between the Neanderthals and the Homo habilis come into sharp focus. The Homo habilis have developed special tools: a small board with a hole in it and a rounded stick to twist to create fire whenever needed—a radical innovation appreciated even by the dim-witted Neanderthals. They have more complex vocalizations than the grunts, groans, and growls of the Neanderthals. They beautify themselves with rudimentary paints. They live in sophisticated huts, organized in patterns comparable to that of the friendliest cul-de-sacs. They cultivate plants and animals—so critical, Jared Diamond argues, to shifts in the evolution of human culture. They prefer face-to-face sex. And they laugh.
In one scene, the three Neanderthals and their new consort are reclining in the dappled light of a shady tree, grooming, scanning the environment, picking bugs out of the air to eat. Out of the blue a rock bounces off one of the male’s jutting foreheads, prompting a scratch on the head, a cursory look around, and then a return to a quiet state of mindless digestion. The Homo habilis witnesses this simplest form of humor (I spent a good part of my youth bouncing harmless objects—acorns, olives, Good & Plenties—off my brother’s head), and breaks into laughter. The three Neanderthals have no idea what to make of the weird sounds emanating from her mouth.
The thesis that laughter represents a critical evolutionary shift in hominid evolution is not as far-fetched as one might imagine. It is a point that evolutionists Matthew Gervais and David Sloan Wilson have made. The laugh might rightfully lay claim to the status of toolmaking, agriculture, the opposable thumb, self-representation, imitation, the domestication of animals, upright gait, and symbolic language—an evolutionary signature of a great shift in our social organization, accompanied by shifts in our nervous system. What separates mammals from reptiles are the raw materials of laughter—play, and the ability to communicate with the voice (when’s the last time you heard the family gecko howl for a nibble of your salmon or purr for a scratch behind the ears?).