THE ANIMAL FILES

Sumatran orangutan

Pongo abelii

A branch can be a path—or a carefully prepared tool.

For a Sumatran orangutan, the canopy is both a route and a store of food.[1]

Follow the evidence ↓
Sumatran orangutan
Image: Andrew Regan · Commons · CC BY 3.0
Moving through flexible trees
Multiple supports help canopy travel.[1]
Sticks with a purpose
Prepared sticks help obtain some hidden foods.[1]
Fruit with other courses
Fruit is important, but insects also contribute.[1]

Moving through flexible trees

Slow movements, long contact with branches and multiple supports characterise canopy travel. A branch bends under weight, so the route must accommodate moving rather than rigid footholds.[1]

Sticks with a purpose

At Suaq Balimbing, wild orangutans have been observed modifying sticks for food extraction. Tasks include reaching insects and dealing with hairs around Neesia seeds. Tools differ with the task, making preparation part of the behaviour. These are observations from a studied population, not a claim that every individual carries an identical toolkit.[1]

Fruit with other courses

Figs, jackfruit and other fruits appear in the diet alongside insects and additional plant material. Natural hollows in trees can provide collected water.[1]

A COMMON MIX-UP

Does observing tool use once mean all individuals use that tool?

No. The behaviour is documented in particular contexts and populations; distribution of a skill needs its own evidence.[1]

TRY A LITTLE REASONING

Why is a flexible branch unlike a fixed ladder rung?

Reveal the explanation

It moves under the ape's weight, so support choice, contact and movement must accommodate bending.[1]

Sources & editorial notes

Adapted and translated from the cited Wikipedia revisions, with source-linked reasoning. Image credit and licence are listed separately above.

Adapted and translated from Wikipedia contributors; exact revisions are linked below. CC BY-SA 4.0

  1. Wikipedia contributors — Sumatran orangutan (cited revision)
  2. NCBI Taxonomy — Pongo abelii

Last fact check:

One discovery leads to another

Western gorillaA large ape follows a changing fruit calendar.Gorilla gorilla ↗BonoboFruit eaten today can become a seed journey through the forest.Pan paniscus ↗ChimpanzeeA stick can become a feeding tool, but not every group uses it alike.Pan troglodytes ↗