Humans share the tool belt
Once upon a time, we were taught that humans are the only
animals that fashion tools.
We were separate from the beasts. We might be earthbound, slower
than many other animals, hairless and weak. But we were divinely
endowed with large brains, and hands that allowed us to shape the
environment around us, to make tools and weapons as no other
creature can.
Humans share the tool belt
Once upon a time, we were taught that humans are the only animals that fashion tools.
We were separate from the beasts. We might be earthbound, slower than many other animals, hairless and weak. But we were divinely endowed with large brains, and hands that allowed us to shape the environment around us, to make tools and weapons as no other creature can.
That gap just closed a little. First, as we came to understand the structure of life by probing DNA, we began to realize how little separates us from many animals. Observers long ago watched apes using twigs to fish tasty termites from their burrows. Even birds have been spotted using objects at hand (beak?) in pursuit of their quarry.
Now, biologists in the West African savannah report observing chimpanzees not just using tools, but also fashioning them.
Naturally, the tools are weapons. I would guess that the first human to craft a tool might sharpen a stick and harden it in the embers of a fire. The need for food would be a powerful motivator. The stone knives and scrapers would have followed the advent of weapons.
So go the chimps.
According to a story last Friday in the Washington Post, researchers in Senegal watched as the apes used a multi-step spear-making technique. The researchers also revealed that the innovators of the process tend to be the females, an observation that should prove profoundly satisfying to about half the readers of this column.
Using hands and teeth, the chimps were seen tearing off side branches of long, straight sticks, peeling back the bark and sharpening one end.
The spears were then used like harpoons, as the apes thrust them into hollows in branches and trees in attempts to spear bush babies – small monkeylike animals that spend their days sleeping in, you guessed it, tree hollows.
The evidence of tool use among chimpanzees is decades old, but creating hunting weapons is a breakthrough described as “stunning” by Craig Stanford, a primatologist and USC anthropology professor.
The apes that found adoring audiences in old movies have been seen throwing rocks and using branches as clubs, but “really fashioning a weapon to get food – I’d say that’s a first for any nonhuman animal,” Stanford said.
While most chimpanzees inhabit forested sites, the animals studied are in more open savannah, a landscape believed to be very much like the one in which humans first evolved.
Perhaps the relative lack of concealment forces the development of tool-making. The article noted the standard chimpanzee hunting technique is to chase a monkey or other prey, grab it by the tail and then slam its head against the ground.
Adrienne Zihlman, a UC Santa Cruz anthropologist, said the work supports existing evidence that female chimps are most likely to be the innovators in a troop, and the ones most likely to share the knowledge, according to the Post report.
“Females are the teachers,” Zihlman said. “They are efficient and innovative, they are problem-solvers, they are curious.”
Before anyone gets two smug in this emerging gender skirmish, there’s a reason for the apparent difference, and it’s born of necessity.
“They are pregnant or lactating or carrying a kid for most of their life,” Zihlman said. “And they’re supposed to be running around in the trees chasing prey?”
Thanks, Professor Zihlman. I feel better about being a guy already.
