The scientist squats on the ground and demonstrates a rudimentary use of tools. He digs into a nest of ants and deftly scoops the stick swarming with insects toward his mouth. Slurp! He gobbles the culinary treat and smacks his lips in pleasure.
"You can quite see why they like them," says anthropologist Dr. Richard Wrangham into the camera, as he wipes a stray ant or two from his chin.
The moment comes late in tonight's fascinating new National Geographic special, "The New Chimpanzees" (8 p.m.-9 p.m., WBAL, Channel 11), that documents how closely chimpanzees resemble humans in their behavior -- both admirable and regrettable.
Narrated by actress Linda Hunt, the program examines recent research and observations in Africa by a number of scientists who have taken up the work of pioneering primate researcher Jane Goodall.
Dr. Wrangham, for example, is pursuing a theory that chimpanzees may use a rudimentary form of medicine.
He has observed some chimps in the group he studies in Tanzania's Gombe National Park swallow a certain leaf, perhaps to eliminate worms.
"It's still an emerging story . . . but it became particularly clear that those individuals who had the parasites were the ones swallowing the leaves. They really do seem to know about dosing themselves," explains Dr. Wrangham in a recent telephone interview, from his office at Harvard University in Cambridge, Mass.
He appreciates the irony that chimpanzees have long been used in experiments to develop medicine for humans.
"My great dream is that, in fact, it would turn out we would gain a new medicine from them," he says, adding, "it would be great public relations" for a species that is endangered in the wild.
As for the on-camera eating of ants, the scientist says such behavior is part of his discipline in studying the species whose DNA, or genetic makeup, is 97 percent identical to that of humans.
"They're a little bit lemony," he says of the taste, explaining: "My rule in the wild is that I'll eat anything the chimps eat. This is one of the nicer things."
Earlier in the show, chimpanzees' use of sticks to chow down on ants is documented as not only a tool-manipulation skill, but one that is patiently taught to youngsters.
We also see remarkably human-like maternal behavior, especially a mother whose child has died.
And we are introduced to a previously little-known species of similar primate known as the bonobos, whose social structure has evolved into one notably different from that of chimps.
In the bonobos' society, females seem to have equal leadership status with males.
In addition, diverse and frequent hetero- and homosexual contact occurs among the animals, apparently as a means of forming bonds and mitigating conflict.
"It is amazingly close to the perfect human society," observes Dr. Wrangham of the bonobos, who have been studied for 22 years by Dr. Takayoshi Kano. Dr. Wrangham adds that these animals show a skill humans could use: "a capacity for men and women to live together without conflict."
Viewers should know that "The New Chimpanzees" has some unpleasant moments, also stemming from the species' similarity humans. Chimps make war, for example, and as seen in a particularly gruesome scene, sometimes engage in fratricide and cannibalism.
"It's so extraordinary that there are only two species in the world in which males bond and specifically go out to kill others of their species. It can hardly be chance that it's our closest relatives and ourselves," says Dr. Wrangham.
Taking note that a 10-year-old female in the newly opened "Chimp Forest" exhibit of the Baltimore Zoo gave birth last month, Dr. Wrangham says chimpanzees face an odd pair of problems.
Although endangered in their wild habitats, they are proliferating in captivity around the world.
"I'm all for the educational component [provided by zoos]," Dr. Wrangham says.
But he adds, "We're just desperate to stop breeding in captivity. . . . They're going to live 50 or 60 years."