- News Home
10 April 2014 11:44 am ,
Vol. 344 ,
Since 2002, researchers have reported that agricultural communities in the hot and humid Pacific Coast of Central...
Balkan endemic kidney disease surfaced in the 1950s and for decades defied attempts to finger the cause. It occurred...
The Pyrenean ibex, an impressive mountain goat that lived in the central Pyrenees in Spain, went extinct in 2000. But a...
Tight budgets are forcing NASA to consider turning off one or more planetary science projects that have completed their...
Ebola is not a stranger to West Africa—an outbreak in the 1990s killed chimpanzees and sickened one researcher. But the...
In an as-yet-unpublished report, an international panel of geoscientists has concluded that a pair of deadly...
Tropical disease experts tried and failed before to eradicate yaws, a rare disfiguring disease of poor countries. Now,...
- 10 April 2014 11:44 am , Vol. 344 , #6180
- About Us
Walk Before You Talk--or Chuckle
21 June 2001 7:00 pm
TORONTO--Watching chimps at play has led one researcher to conclude that humans must have started walking upright before they developed speech. A quadruped's breathing apparatus, according to a report here on 17 June at the American Psychological Society meeting, makes it impossible to talk and run at the same time.
Most laughter research is done on humor, said developmental neuroscientist Robert Provine of the University of Maryland, Baltimore County. But his research focuses on laughter's relationship to social relationships and play. This led Provine to Yerkes Regional Primate Research Center in Atlanta, where he observed what he believes is the evolutionary precursor of human laughter: the "ritualized panting" of chimps during play.
Chimps have to take a separate breath for each gasp, Provine notes, while humans can burst out with a "ha-ha-ha" all in one expiration. He also noted that when quadrupeds run they have to take a breath with every step, which makes it impossible to develop the sophisticated respiratory control necessary for speech. Thus, he says, bipedality, which allowed "the redirection of breathing in the service of soundmaking," enabled humans to evolve speech.
Other researchers have tied bipedality to speech for different reasons. Philip Lieberman of Brown University in Providence, who studies the evolution of the human vocal tract, says Provine's theory fits with his own research. Brain structures that regulate bipedal locomotion are also essential in regulating speech, he says. Thus walking on two legs may have helped shape the brain in a way that was later used for speech and syntax.