Behaviour and cognitionbehaviour
Tool use
Not "which animals pick things up" — which ones pay a price now for a payoff later.
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
Every organism below has been linked to this page because the evidence links them. Each one 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 case of tool use here: 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
Set side by side for 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 are capable of.
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.
Every organism below has been linked to tool use because the evidence links it. 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.
Royal Society Open Science
Tool bending in New Caledonian crows
Birds routinely bent plant material while making tools, and hooked tools were produced as a matter of course rather than as a rare feat.
Nature
Discovery of species-wide tool use in the Hawaiian crow
The great majority of adults used tools proficiently, and juveniles developed the behaviour without being taught, indicating a species-wide predisposition rather than an individually learned trick.
PLoS ONE
Using the Aesop’s Fable paradigm to investigate causal understanding of water displacement by New Caledonian crows
Crows chose sinking over floating objects, solid over hollow, and water over sand.
Current Biology
Spontaneous innovation in tool manufacture and use in a Goffin’s cockatoo
The bird spontaneously broke splinters from a wooden beam and used them to rake the nut within reach, then repeated and refined the behaviour, adjusting the material it selected and shaped.
Current Biology
Defensive tool use in a coconut-carrying octopus
Octopuses excavated, cleaned and carried coconut shell halves across the sea floor — walking awkwardly on stiffened arms while holding them — then assembled them into a shelter when threatened.
Proceedings of the Royal Society B: Biological Sciences
Do New Caledonian crows solve physical problems through causal reasoning?
Crows that had learned to avoid the trap transferred correctly to versions that looked different but worked the same way, and failed on versions that looked the same but worked differently — but performance was inconsistent across individuals and tasks.
PLoS ONE
Why do dolphins carry sponges?
Sponging is concentrated in particular matrilines, is learned almost exclusively by daughters from their mothers, and lets dolphins forage in deep channels for fish that lack swim bladders and cannot be found by echolocation alone.
Proceedings of the National Academy of Sciences
Cultural transmission of tool use in bottlenose dolphins
Nearly all spongers descended from a single matriline and shared a mitochondrial haplotype, with the pattern not explained by nuclear genetic relatedness or by habitat — consistent with vertical social transmission from mother to calf.
PLoS Biology
First Observation of Tool Use in Wild Gorillas
One female used a branch as a walking stick, apparently testing water depth ahead of her while wading.
American Journal of Primatology
Western gorilla diet: a synthesis from six sites
Western gorillas are substantially frugivorous where fruit is available, falling back on leaves, stems and pith when it is not.
Science
Shaping of hooks in New Caledonian crows
The bird bent straight wire into a hook and used it to lift the bucket out, repeatedly and in several variations.
Animal Behaviour
Cognitive behaviour in Asian elephants: use and modification of branches for fly switching
Elephants routinely shortened branches or removed side shoots to produce a more effective switch, and modified branches were associated with better fly control.
Nature
Cultures in chimpanzees
Thirty-nine behaviours, many of them involving tools, varied between sites in ways that ecology did not explain.
Nature
Manufacture and use of hook-tools by New Caledonian crows
The birds manufacture two distinct tool types to a consistent design, including hooked twigs, and use them to winkle out grubs.
This page is a stop on a longer route
A guided journey reads several subjects in a deliberate order, with an argument for why one follows another. You can join in the middle.
Where to go from here
Each of these follows from something on this page — a relationship in the evidence, a claim people ask about, or the next mechanism along.
They know your face. What that actually means is more specific — and more interesting — than the headline.
Crows · species group
A second, independent invention of a complex mind — with two-thirds of its neurons in its arms.
Octopuses · species group
They can tell which people are dangerous by voice alone — and they may call each other by name.
Elephants · species group
They feel the electric field around a flower — with their hair.
Bumblebees · genus
The colony solves problems no ant is solving. That is not a metaphor; it is the mechanism.
Ants · higher taxon
A dolphin invents its own whistle as a calf and answers to it forty years later — even when the voice is stripped out.
Dolphins · species group
How complete this page is, and what it is still missing
NatureHQ publishes its own gaps. This page is at 68% completeness against what we would call a finished subject, and was last reviewed on 2026-08-09. It carries 9 claims and answers 14 mapped search questions.
- 1 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.