Many people still bristle at the idea that chimpanzees can have “cultures.” The evidence is accumulating, however, as documented in “Almost Human,” an article found in the April, 2008 edition of National Geographic. The article was written by Mary Roach, with incredible photos by Franz Lanting.

In 2007, an Iowa State University anthropologist named Jill Pruetz reported that while studying chimpanzees in the field (two years earlier) she noticed a female chimp:

Sharpening a branch with her teeth and wielding it like a spear. She used it to stab at a bush baby–a pocket-sized, tree dwelling nocturnal primate that springs from branch to branch like a grasshopper. Until that report, the regular makings of tools for hunting and killing mammals had been considered uniquely human behavior. Over a span of 17 days at the start of the 2006 rainy season, Pruetz saw the chimps hunting bush babies 13 times. There were 18 sightings in 2007. It would appear the chimps are getting creative.

Pruetz has spent more than four years studying the Fongoli chimpanzees (they are savanna-woodland chimps from eastern Senegal, across the border from western Mali). Pruetz has been habituating the Fongoli chimps (allowing them to get used to her) for the past three summers. She has done this hot, filthy and exhausting work six days a week, from dawn to dusk. She has gotten sick with malaria seven times. In the course of watching the Fongoli champs, she has also noticed them engaging in other behaviors unique to these Fongoli chimps: “soaking in a water hole and passing the afternoon in caves.”

Spearing bush babies is only the most recent of the many cultural behaviors documented regarding chimpanzees. Jane Goodall was the first to report seeing chimps making tools (for termite fishing). The world-famous bonobo named Kanzi has learned hundreds of symbols to communicate. This National Geographic article reports numerous other behaviors unique to various communities of chimpanzees have been documented. Some communities of chimpanzees use rocks to smash open nuts much like we would use hammers and anvils. Other champs chew leaves into a spongy wad to soak up water for drinking. Several communities of chimps cool down by a wading into pools of water. Numerous communities of chimpanzees throw rocks, sometimes as weapons and other times as part of displays.

The article notes that chimpanzees and humans share between 95 and 98% of their genomes. The article cautions, however, that this is “less meaningful than it sounds. Humans share more than 80% of their gene sequence with mice, and maybe 40% with lettuce.”

The author of this article, Mary Roach, was surprised to learn that chimpanzees’ yawns are contagious, “both among each other and to humans.” In the course of writing this article, she also learned that chimps laugh, and even get upset if someone laughs at them. They sometimes spit in disgust. Some chimps have been known to adopt other species of animals (one chimp named Tia adopted a small kitten).

Chimps get up to get snacks in the middle of the night. They lie on their backs and do “the airplane” with their children. They kiss. Shake hands. Pick their scabs before they’re ready.

The observations reported in this article certainly blur the cultural boundary between humans and chimpanzees. These sorts of observations will make many people upset, however. They want to believe that humans are sui generis among animals, of their own kind and that there is no real comparison, certainly no cultural comparison between humans and animals of any other species.  In fact, there are hordes of people who resist thinking of humans as animals at all (and see here) (and here and here).

Perhaps it won’t soothe the critics to view the situation in the way suggested by a famous evolutionary biologist:

It is perhaps less problematic to view the situation as does The Third Chimpanzee author Jared Diamond: Not that chimps are a kind of human, but that humans are a kind of chimp.

This is an article that truly transported me around the world. It made me feel that I was almost there, observing these magnificent animals. As I’ve commented before, this type of writing and photography is nothing out of the ordinary for the National Geographic.