Consider the exploits of Frenchman Joseph Pujol, history’s most melodic master of flatulence.
Early in life, in the 1860s, he discovered a rare ability to draw air into his rectum—to use as an organ of ingress one primarily given to egress. Expelling the air, he performed selections of up to 15 seconds of such animal sounds as a rooster’s crow, creditable imitations of such musical instruments as the violin and trombone, and even a rendition of “La Marseillaise”—the tune, not the lyrics—that moved his audiences to gales of laughter.
Hence, Pujol’s professional name, “Le Pétomane,” which translates as “fartomaniac.” His repertoire was so vast and compelling that in his glory days, at such venues as the Moulin Rouge, he earned far more than “The Divine Sarah” Bernhardt—“the most famous actress the world has ever known.”
For serving as a special case, Pujol has an honored place in Curious Behavior: Yawning, Laughing, Hiccupping, and Beyond, Robert R. Provine’s engaging and seriously amusing new book, just out from Harvard University Press.
With such chapter headings as “Tickling,” “Itching and Scratching,” and “Farting and Belching,” the book addresses often-embarrassing expressions of common humanity. As an electrophysiologist and more recently a “sidewalk scientist,” Provine, a professor of psychology and neuroscience at the University of Maryland, Baltimore County, has been studying innate human behaviors for more than 40 years.
Neither farting nor yawning, belching, or sneezing are, as Provine unsurprisingly notes, behaviors that have set the scientific world alight. They are instead generally considered undignified, for reasons he both seeks to explain and ultimately dismisses. He points out that, as instinctive or autonomic acts, they say much about humans’ evolutionary trajectory, and hence inner and social life.
Not that scientists’ relative neglect of such actions is surprising, he allows: Biologists focus on processes in physiology or genetics; social scientists consider environmental influences on behavior; physicians treat such symptoms as sneezes or coughs but seldom study them. But those same acts suggest ways to understand the functioning of the human brain, and how it differs from that of other species, suggests the author.
Why is it, for example, that yawning and other behaviors, including laughter, are contagious? That reveals a role for yawning in not only registering fatigue, but also in the development of human sociality and empathy, he writes.
His chapter on the yawn typifies his approach in others. He analyzes yawns’ physical characteristics—they resemble slow sneezes, and like sneezes are akin to orgasms, demonstrating that multiple innate acts tap a similar neuromuscular substrate and have a common evolutionary course. An ancient one, apparently. Virtually all vertebrates yawn, suggesting that it is “a relic of our developmental and evolutionary past.”
So contagious are yawns that “simply discussing yawns triggers yawns.” But his experiments have shown that it is not the yawning open mouth that triggers yawns in others, but rather “our neurological yawn detector responds to the overall pattern of the yawning face, including the squinting eyes.”
Mentioning yawning will induce yawning in test subjects in 92 percent of cases within 30 minutes. Reading about yawning for five minutes induces yawning in 20 percent of test subjects during the five minutes, versus 11 percent for a control group who read about hiccupping. “It’s amusing to see one-half of a large lecture class yawning while the other half is not,” he observes.
Evidence that yawning contagion is a factor in the development and evolution of sociality and perhaps empathy comes from consideration of “mirror neurons” in the human brain, he says. Those seem to play a role in imitation, intuition, empathy, language, and realizing that others have minds, too. He speculates that yawning could relate to synchronizing bedtime among members of tribes—it can transform group members into a “collective super-organism.”
Provine similarly analyzes tickling, which appears linked to various forms of play, including sex. It is related, then, to laughter, the sound of physical play—laughter is a form of primal, primate onomatopoeia in which patterns of expired air are harnessed to signal playfulness.
More generally, tickling—whether of the pleasurable or intrusive variety—serves as a neurological mechanism for allowing individuals to differentiate themselves from others, which in evolutionary terms would have been crucial for the emergence of personality and social life. He also suggests that it provides “the starting point of programming personhood into robots.”
As for laughter, its suggestive dimensions include that it requires bipedality—walking upright. Bipedality frees the thorax of its role of supporting the skeleton. Humans, unlike chimpanzees, for example, can breathe less often than they stride, and that permits them to use air in their lungs to make such sounds as laughter. Laughter, in that sense, appears to have been a step along the path to the evolution of speech.
Provine says he began his studies of often-marginalized, mundane human behaviors when he tired of inserting electrodes into nerve cells in a laboratory, but wished to retain rigorous approaches in what he calls a “sidewalk neuroscience” mode of inquiry. Cheaply and simply, he observed such subjects as graduate students, for example—to track their behaviors.
While akin to Freud’s study of the unconscious, or B.F. Skinner’s attention to how people behave rather than claim about their motives, Provine’s analysis of shared, instinctive behaviors owes much to ethology. That evolutionarily based, biological study of behavior, championed by the European researchers Konrad Lorenz, Nikolaas Tinbergen, and Karl von Frisch, “is more concerned with the adaptive (evolutionary) significance of behavior than is typical of American psychology, with its greater focus on learning, environmental influences, and carefully controlled laboratory experiments,” Provine writes.
Focusing on phenomena that offer insights into how the brain produces and controls behavior, including primal social behavior, he writes, it “reminds us that we are sometimes unaware, neurologically programmed herd animals.”
