Animal communication

Biologists generally describe communication as a signal produced by one individual that influences the behaviour of another, where the signalling structure is associated with that effect rather than arising by accident. A signal is a trait — a call, a posture, a chemical, a colour patch — that is associated with conveying information; the receiver then responds. Defining it this way keeps the focus on what can be observed: the signal sent and the response that follows.

This framing deliberately stays cautious about inner states. When a ground squirrel calls and others flee, we can document the call and the flight reliably; we cannot directly observe whether the caller "intends" to warn anyone, and careful researchers separate the behaviour they measure from any inference about intention or feeling. Signalling is also not always cooperative — some signals function in deception, manipulation, or competition — so "communication" should not be read as a friendly conversation by default.

It also helps to remember that signals are shaped by an animal's sensory world, which differs from ours. A scent mark, an ultraviolet wing patch, or an infrasonic rumble may carry information an unaided human cannot perceive at all, which is one reason these systems took so long to study and remain partly understood.

Alarm calls are among the best-studied vocal signals. In long-term work on vervet monkeys, researchers reported that different calls were associated with different predator types and with different escape responses — one pattern linked to aerial threats, another to ground threats. This led to the idea of "functionally referential" signals: calls that behave as if they pick out something in the world. The interpretation remains debated, and researchers are careful not to equate such calls with words; the calls are produced in particular contexts and reliably change listeners' behaviour, which is a strong claim on its own without invoking language.

Bird song is a classic case where both inherited tendencies and learning matter. In several studied songbirds, young birds need to hear adult song during a sensitive period to develop normal song, and isolated birds develop abnormal song — evidence that learning is involved, not pure instinct. Song is commonly associated with territory and mate attraction, and some species show regional "dialects." These patterns are documented in particular species and should not be generalised to all birds, many of which use simpler calls rather than complex learned song.

Whale song is best known in humpback whales, where males within a population sing long, hierarchically structured songs that change over time, with the shared version gradually shifting across a season and across populations. The song's full function is not settled and is usually linked to breeding context. It is a striking, structured acoustic display — but structure and change over time are not the same as language, and researchers describe it as a communication and possibly socially transmitted signal rather than speech.

The honeybee waggle dance is one of the most famous animal signals. A forager returning to the hive can perform a looping run with a central "waggle" segment; across many observations, the angle of that segment relative to gravity is associated with the direction of a resource relative to the sun, and the duration of the waggle is associated with distance. Other bees attend to the dance and are more likely to fly out toward the indicated area. The behaviour was characterised in detail by Karl von Frisch and has been examined extensively since.

This is remarkable precisely because it conveys information about something distant and out of sight, using a shared, somewhat standardised code within the colony. At the same time, it is narrow: it concerns foraging-related locations and a few related contexts, the "vocabulary" is not open-ended, and bees do not appear to recombine dance elements to express arbitrary new ideas. It is a powerful, specialised communication system — and a clear example of why communication need not be language.

Descriptions of colonies should also avoid human-society analogies. Phrases borrowed from human monarchy or governance are misleading for insect colonies, whose coordination arises from many individuals responding to local cues and signals, not from deliberation in the human sense.

Chemical signalling is widespread and easy to underestimate because humans rely on it less. Many mammals scent-mark, and many insects release pheromones; these chemical signals are associated with information such as identity, reproductive state, or the presence of an individual in an area. Because chemicals persist, scent can carry a message after the sender has gone — a property sound and most visual displays lack. The specifics vary enormously between species, so claims should stay tied to the species actually studied.

Visual displays include postures, movements, and colour. A spread tail, a raised crest, a flash of bright colour, or a rapid skin-pattern change (as in some cephalopods) can all function as signals in courtship, competition, or warning. Some colour signals are "honest" indicators tied to condition, while others function in bluff or mimicry; the point is that a display's appearance and its function are separate questions that have to be tested, not assumed.

Many species combine channels — a display paired with a call, or a scent paired with a posture — and the same signal can serve more than one function depending on context. This multimodal, context-dependent quality is part of why simple one-signal-one-meaning descriptions are usually too tidy.

Linguists have long described human language using a set of design features. Several are especially useful here: displacement (referring to things distant in space or time), productivity or open-endedness (combining a finite set of elements into endless new messages), and arbitrary, learned, recombinable units organised by grammar-like rules. Human language has all of these together; most animal communication systems, as currently understood, show some features in limited form but not the full combination.

The honeybee dance shows a kind of displacement yet is not open-ended. Alarm calls can be context-specific yet are not freely recombined into new sentences. Some songbird and whale songs are structured and learned yet are not used to express arbitrary new propositions. Saying these systems are "not language" is not a put-down; it is a precise statement that they work differently from human speech, and they are impressive on their own terms.

Studies of language-trained animals (for example great apes or some parrots) have produced genuinely interesting results about learning and association, but they are also heavily debated, and researchers caution against over-reading them as evidence of human-style grammar. Whatever such studies show about trained behaviour, they do not establish that any non-human species uses full human language in the wild. The careful position is to credit each species with what is observed and stop there.

A few habits keep claims about animal communication honest. Describe what is observed — the signal and the response — and treat statements about intention, meaning, or emotion as inferences that need evidence and caveats. Avoid generalising from one well-studied species to a whole group: "some studied songbirds learn their songs" is defensible; "all birds learn language" is not. And be wary of viral clips and confident headlines, which often outrun what the underlying research actually supports.

It is also worth separating instinct and learning less rigidly than popular accounts do. Bird song again illustrates this: many species combine an inherited predisposition with learning during a sensitive period, so framing a behaviour as purely one or the other usually distorts it. Similarly, avoid "evolved in order to" phrasing; a signal is better described as associated with, or as appearing to function in, a given role.

For deeper reading, rely on institution-backed sources — peer-reviewed ethology and animal-behaviour literature, university museum species accounts, and similar references — rather than pet blogs or social media. FaunaHub's approach to choosing and reading such sources is described in the animal research sources guide.

How the claims on this topic are studied and read:

• Communication vs languageHow rich animal signalling differs from human language — bee dance, whale song, and bird song.

How whole groups of animals show this behavior:

• Parrot learning
• Cetacean behavior
• Amphibian communication
• Eusocial insects

This guide is part of FaunaHub's animal intelligence & behavior cluster. For how these claims are sourced, see animal research sources, and for the biology behind behavior, see animal senses & adaptations.