Nut-bashing capuchin monkeys and human evolution


This 2013 video is called Brown capuchin monkeys breaking nuts – One Life – BBC.

From National Geographic:

Nut-Bashing Monkeys Offer Window Into Human Evolution

Brazil’s bearded capuchins know how much force is needed to crack open a nut—a surprisingly human-like skill, a new study says.

By Liz Langley

PUBLISHED July 18, 2015

Give me a hammer, and I’d probably end up bashing my thumb with it. When it comes to tool use, dexterity counts.

So when Saturday’s Weird Animal Question of the Week heard about the famous nut-crushing monkeys of Brazil, we took the prerogative to ask: “How can these monkeys crack nuts so accurately?”

First off, these bearded capuchins open tough palm nuts by putting them on “anvils,” including logs and boulders, and hammering at them, according to research by National Geographic explorer Dorothy Fragaszy of the University of Georgia at Athens.

Fragaszy and colleagues already knew the monkeys are choosy about their nut-cracking tools, for instance by selecting rocks that are heavier than themselves. (Related: “Hercules Monkeys Lift Stones to Crack Nuts.”)

But she didn’t know how the capuchins can skillfully get to their snack without smashing it to smithereens—until now. New observations in the southeastern state of Piauí, Brazil (map) reveal that the animals carefully regulate the force they use in nut-cracking.

After each strike, the monkeys evaluate the condition of the nut and then tailor the force of the next blow accordingly. (See National Geographic‘s monkey pictures.)

That’s called dexterity, “a very surprising skill we never expected to find in a non-human animal,” says Madhur Mangalam, also of the University of Georgia at Athens. (Read about how clever crows use one tool to acquire another.)

“We thought they’d try to break the nut with as much force as they can,” adds Mangalam, who’s a co-author with Fragaszy on a recent study published in the journal Current Biology.

Monkey Practice, Monkey Do

The monkeys’ impressive skill also offers some insight into the evolution of human tool use, the scientists say.

Take stone knapping, or using one stone to strike another in order to shape it into an arrowhead or other useful object—a strategy used by many early humans.

“A novice knapper sort of bangs one stone against another and produces nothing very much that’s usable,” Fragaszy says. (Read how a wrong discovery led to the discovery of the oldest stone tools.)

A skilled knapper, on the other hand, controls the force of the stone “hammer”—much like capuchins.

Our ancestors’ nut-cracking skills likely “allowed us to have a more complex skill of stone knapping,” Mangalam adds. (See “Human Ancestors May Have Used Tools Half-Million Years Earlier Than Thought.”)

Another thing the monkeys have in common with people: They both have to learn their expertise.

Capuchins take a couple of years to learn nut-cracking, which takes a lot of practice and playing with tools nuts and stones in different ways to get it right, Mangalam says.

Practice makes perfect—sounds anything but nutty to us.

7 thoughts on “Nut-bashing capuchin monkeys and human evolution

  1. Pingback: Ancient human species discovered in South Africa? | Dear Kitty. Some blog

  2. Pingback: Most threatened primates top 25 | Dear Kitty. Some blog

  3. Pingback: Howler monkeys’ eyes, new research | Dear Kitty. Some blog

  4. Pingback: Goffin’s cockatoos’ tool use | Dear Kitty. Some blog

  5. Pingback: Chimpanzees, hogs help monkeys, guineafowl | Dear Kitty. Some blog

  6. Pingback: Capuchin monkeys’ stone-tool use evolution | Dear Kitty. Some blog

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.