behaviour
Tool use
Tool use means acting on the environment with an object held or manipulated for the purpose. It is rarer than popular writing suggests, and the harder standard — modifying an object to make it work better — is rarer still.
Tool use was once offered as the thing that separated humans from everything else. It has not held up, but the retreat has been orderly rather than total: the animals that genuinely make and modify tools are still a short list, and they are scattered across the tree of life rather than clustered near us. A crow on a Pacific island, an octopus on Indonesian sand and an elephant in Nepal have nothing in common except that each pays a cost now for a benefit later. That cost is what separates tool use from opportunism, and it is the criterion this page applies.
Quick facts
- The useful distinction
- Using an object, versus modifying one to work better
- Why the cost matters
- Carrying a shell slows an octopus down — that is what makes it a tool and not a shelter
- Among crows
- Two species out of roughly 45 use tools habitually
Where this appears
Assembled from the knowledge graph. Each entry carries its own evidence and its own limits.
Ants
high confidencecultivates a crop and manages its parasites
Scope: fungus-growing ants and their antibiotic-producing bacteria
Crows
high confidencemanufactures hooked tools — in two species only
Scope: two island crow species out of roughly forty-five — do not generalise further
Dolphins
high confidencecarries a sponge on the beak while probing the seafloor
Scope: one matriline in Shark Bay, Western Australia — do not generalise further
The narrowest tool-use edge in the graph: a handful of animals in one bay, almost all female.
Elephants
moderate confidenceshortens branches to make better fly switches
Scope: Asian elephants
Gorilla
moderate confidenceuses tools for balance and depth-testing, and almost never for food
Scope: western lowland gorillas; two observed instances
The edge exists partly to hold the contrast: chimpanzee tool use is extractive and routine, gorilla tool use is postural and rare, and the difference tracks what their food requires rather than what they can do.
Octopuses
high confidencecarries shells for shelter, at a cost to movement
Scope: veined octopuses
Definitions vary, but the working standard in the literature is close to this: an object, not attached to the substrate, held or carried and used to change the position or condition of something else. Two refinements do most of the work in practice.
- Manufacture. Shaping the object first — snapping a branch to length, bending a twig into a hook — is a considerably higher bar than using one as found.
- Cost. Carrying a tool to somewhere it might be needed, at a price paid now, is evidence that the behaviour is not simply opportunistic.
Neither criterion requires the animal to understand anything. They are behavioural standards, and an animal can meet them without holding a plan in any sense we would recognise.
Words used here
- Tool manufacture
- Modifying an object before use, rather than using it as found.
The organisms below are linked to tool use in the NatureHQ knowledge graph. Each carries its own evidence and its own scope, because the phrase "uses tools" means something quite different for a New Caledonian crow, which manufactures to a standard design, and for an octopus, which carries a found object.
Why do island species dominate the list of habitual tool users?
Why it matters: Both tool-using crow species are island birds. If isolation, or an empty ecological niche, is what drives it, that says something general about how the behaviour arises.
How much tool use goes unrecorded because nobody has watched closely enough?
Why it matters: Two of the clearest cases here — the coconut-carrying octopus and species-wide tool use in Hawaiian crows — were found only when someone looked properly.
The research behind this page
14 studies, newest first. Each one has a page explaining what it found and what it could not show.
2016 · Royal Society Open Science
Tool bending in New Caledonian crows
2016 · Nature
Discovery of species-wide tool use in the Hawaiian crow
2014 · PLoS ONE
Using the Aesop’s Fable paradigm to investigate causal understanding of water displacement by New Caledonian crows
2012 · Current Biology
Spontaneous innovation in tool manufacture and use in a Goffin’s cockatoo
2009 · Current Biology
Defensive tool use in a coconut-carrying octopus
2009 · Proceedings of the Royal Society B: Biological Sciences
Do New Caledonian crows solve physical problems through causal reasoning?
2008 · PLoS ONE
Why do dolphins carry sponges?
2005 · Proceedings of the National Academy of Sciences
Cultural transmission of tool use in bottlenose dolphins
2005 · PLoS Biology
First Observation of Tool Use in Wild Gorillas
2004 · American Journal of Primatology
Western gorilla diet: a synthesis from six sites
2002 · Science
Shaping of hooks in New Caledonian crows
2001 · Animal Behaviour
Cognitive behaviour in Asian elephants: use and modification of branches for fly switching
1999 · Nature
Cultures in chimpanzees
1996 · Nature
Manufacture and use of hook-tools by New Caledonian crows
Crows
They know your face. What that actually means is more specific — and more interesting — than the headline.
Octopuses
A second, independent invention of a complex mind — with two-thirds of its neurons in its arms.
Elephants
They can tell which people are dangerous by voice alone — and they may call each other by name.
A sense of number
A bird, an insect and a plant, all responding to number — by three completely different mechanisms.
Bumblebees
They feel the electric field around a flower — with their hair.
Ants
The colony solves problems no ant is solving. That is not a metaphor; it is the mechanism.
Dolphins
A dolphin invents its own whistle as a calf and answers to it forty years later — even when the voice is stripped out.
Gorilla
Nobody has ever measured a gorilla being ten times stronger than a person. What they can measure is each other, by ear.
What this page is still missing
NatureHQ publishes its own gaps. This record is at 67% completeness against what we would call a finished subject.
- 2 high-priority search intent(s) not yet covered
- no research from the last few years is attached — check for newer work
- more experiments could be explained in plain English
- no popular claim about this subject has been checked yet
- Primates, the most-studied tool users of all, are not yet represented as subjects.
- Sea otters, dolphins and Egyptian vultures all belong here.
Last reviewed 2026-08-09 · 9 claims · 13 search questions answered on this page