Monkey experiments offer clues on origin of language

Green and vervet monkeys live on either side of Africa and their evolutionary paths diverged 3.5 million years ago, and yet the two species share a hard-wired vocabulary when faced with danger, clever experiments have shown.

The new research, published Monday, sheds light not only on how primates—including humans—respond to threats, but also on the building blocks of language itself.

Vervet monkeys in the savannah of east Africa utter three distinct cries depending on whether they spot a leopard, a snake or an eagle, their three main predators.

Fellow monkeys who hear the cries but cannot see the peril react accordingly: the leopard call sends them scurring up a tree, a snake call prompts them to stand motionless on two legs, and the eagle cry makes them scan the sky while seeking shelter. It’s as if a sentinel is shouting, “Freeze, it’s a snake!”, or “Get off the ground, it’s a leopard!” The discovery thirty years ago of these unique warning cries sparked debate as to whether they were like primitive words, noted Julia Fisher, head of the cognitive ethology laboratory at the German Primate Center in Gottingen, Germany and senior author of a study in Nature Ecology & Evolution. It also raised the question of where they came from. Did young vervets learn them through imitation, were the cries genetically imprinted? To deepen their understanding, Fisher and colleagues set up an experiment with a community of green monkeys in Senegal which they have been observing for more than a decade.

 

Monkey experiments offer clues on origin of language

Green and vervet monkeys live on either side of Africa and their evolutionary paths diverged 3.5 million years ago, and yet the two species share a hard-wired vocabulary when faced with danger, clever experiments have shown. The new research, published Monday, sheds light not only on how primatesincluding humansrespond to threats, but also on the building blocks of language itself. Vervet monkeys in the savannah of east Africa utter three distinct cries depending on whether they spot a leopard, a snake or an eagle, their three main predators. Fellow monkeys who hear the cries but cannot see the peril react accordingly: the leopard call sends them scurring up a tree, a snake call prompts them to stand motionless on two legs, and the eagle cry makes them scan the sky while seeking shelter. Its as if a sentinel is shouting, Freeze, its a snake!, or Get off the ground, its a leopard! The discovery thirty years ago of these unique warning cries sparked debate as to whether they were like primitive words, noted Julia Fisher, head of the cognitive ethology laboratory at the German Primate Center in Gottingen, Germany and senior author of a study in Nature Ecology Evolution. It also raised the question of where they came from. Did young vervets learn them through imitation, were the cries genetically imprinted? To deepen their understanding, Fisher and colleagues set up an experiment with a community of green monkeys in Senegal which they have been observing for more than a decade.