Chicago, IL January 27, 2010 -- Humans and their primate cousins parted ways along the evolutionary road millions of years ago, but despite their divergent paths they still have a few things in common.
That’s part of the news from two special reports on recent scientific findings just published by Encyclopaedia Britannica.
To varying degrees primates respond to tickling, floss their teeth, distinguish right from wrong and appreciate good music. In an article now available on the company’s Web sites, Professor Stephen L. Zegura of the University of Arizona reports on Ardipithecus, the 4.4-million-year-old hominin species discovered in the early 1990s that scientists say constitutes a distinct and structurally more primitive genus from the more famous early human ancestor Australopithecus, which has been known to anthropologists for many years. Evidence suggests that Ardipithecus was only about four feet tall, walked upright when on the ground but still swung from trees. Males of the species were similar in size to females, were invested in child rearing and showed less aggression toward their fellow males than their evolutionary ancestors.
Summarizing recent research, much of it reported last fall in the journal Science, Zegura says that Ardipithecus, fossils of which were unearthed at the Aramis excavation site in Ethiopia, extends our knowledge of human origins back further in time and gets us closer to “the approximately seven-million-year-old hypothetical common ancestor of humans and chimpanzees.”
Seven million years is a long time, but the origins of laughter in humans harkens back even further: 10-16 million years, in fact, according to research described in another Britannica article by Lisa Newbern of the Yerkes National Primate Research Center at Emory University. In “Primate Research: A Key to Understanding What It Means to Be Human,” Newbern reviews recent scientific work from England, Germany, Sweden, the United States and elsewhere that sheds new light on similarities and differences between people and non-human primates.
Scientists have found, among other things, that orangutans, gorillas, chimpanzees and bonobos respond to tickling with laughter. To varying degrees primates also floss their teeth, distinguish right from wrong and appreciate good music. And in a discovery sure to resonate with parents of young children, one study found that infant rhesus macaques manipulate their parents by throwing temper tantrums.
Large differences between us and our nearest non-human relatives do remain, of course, and the article treats those as well.
These and other special reports, which are available online now, will be published next month in the 2010 Britannica Book of the Year.
About Encyclopaedia Britannica
Encyclopaedia Britannica, Inc. is a leader in educational publishing. The company’s encyclopedias and other products can be found in many media, from the Internet to wireless devices to books. A pioneer in electronic publishing since the early 1980s, the company still publishes the 32-volume Encyclopaedia Britannica, along with educational online services such as Britannica SmartMath and Britannica Online School Edition and new printed products such as Britannica Illustrated Science Library. The company makes its headquarters in Chicago.
