Social Learning and Animal Culture: How Traditions Pass Between Animals

Topic: Animal Behaviour & Ethology Subject: Social Learning, Traditions, and Culture in Non-Human Animals Last verified: 2026-09-23

Many animals do not have to work out everything for themselves. A young macaque can pick up a food-washing habit from its playmates, a great tit can learn how to open a feeder by watching its neighbours, and a humpback whale can switch to a new song because the males around it are singing one. When behaviour spreads in this way and then persists as a shared tradition, biologists describe it as culture: "all that is learned from others and is repeatedly transmitted in this way, forming traditions that may be inherited by successive generations" [Whiten 2021]. Once thought to be specific to humans, this cultural form of inheritance has been documented over the past 70 years in all major classes of vertebrates, and recent studies suggest it may extend to insects [Whiten 2021]. Field studies, controlled experiments and statistical tools for tracing how information moves through social networks have made animal culture a mainstream subject, with consequences for evolutionary biology and for conservation policy [Whiten 2021; Brakes et al. 2019].

This article explains how social learning and culture are defined and how animals learn from one another. It then looks at the classic cases, including Japanese macaques washing sweet potatoes and tits opening milk bottles, and at the honest caveats that come with them. It goes on to cover cultures in great apes, whales, fish, insects and migrating ungulates, and ends with why cultural knowledge is increasingly treated as something worth conserving. Birdsong learning, corvid tool use, dominance hierarchies and migration each have their own articles in this series and are mentioned here only where they connect.

Defining Social Learning and Culture

Social learning is learning that is influenced by observing or interacting with another animal or its products. It is distinguished from asocial (individual) learning, in which an animal learns by trial and error without any help from others [Hoppitt & Laland 2013]. Theoretical models of how social learning evolved led Kevin Laland to conclude that it cannot be indiscriminate. Individuals should instead adopt strategies that dictate when they copy others and from whom they learn [Laland 2004].

Social learning is necessary for culture but is not the same thing. A single animal copying another once is social learning; culture requires that the learned behaviour becomes shared within a group and is passed on repeatedly, forming a tradition [Whiten 2021]. A widely used working definition, adopted by an international group of researchers writing on conservation, describes animal culture as "information or behavior—shared within a community—which is acquired from conspecifics through some form of social learning" [Brakes et al. 2019].

Researchers have used two broad approaches to identify culture, especially in wild animals. The ethnographic approach looks for patterns of behavioural variation between populations that cannot be explained by genetic or environmental differences [Rendell & Whitehead 2001]. The experimental approach tests transmission mechanisms directly, for example by training a demonstrator and watching whether the behaviour spreads [Rendell & Whitehead 2001]. Luke Rendell and Hal Whitehead argued that for large, wide-ranging animals such as whales, relying too heavily on experimental evidence is not productive, and favoured the ethnographic approach [Rendell & Whitehead 2001]. Much of the progress described below came from combining the two approaches [Whiten 2021].

Whether animal traditions deserve the word "culture" has long been debated. In an influential critique, Bennett Galef reviewed studies of problem solving by captive primates and two widely cited field cases, sweet-potato washing by Japanese macaques and termite fishing by chimpanzees. He suggested that non-human primates do not learn to solve problems by imitation [Galef 1992]. He concluded that it may be misleading to treat animal traditions and human culture as homologous rather than analogous, and to call animal traditions cultural at all [Galef 1992].

How Animals Learn from One Another

Not all social learning involves copying another animal's actions. William Hoppitt and Kevin Laland describe a range of mechanisms and show how they can be told apart experimentally. They include stimulus enhancement, local enhancement, observational conditioning, response facilitation, social facilitation, imitation, emulation, and forms of coaching or opportunity providing [Hoppitt & Laland 2013]. The simplest mechanisms work by drawing an animal's attention. In local enhancement, a demonstrator draws an observer to a particular place, where the observer then learns for itself; in stimulus enhancement, it draws attention to a particular object or type of object [Hoppitt & Laland 2013]. In emulation, the observer learns about the results of another's actions, such as how an object moves, and then reaches the same result in its own way. In imitation, the observer copies the form of the action itself [Hoppitt & Laland 2013].

These distinctions matter because simple mechanisms can produce traditions that look sophisticated, as the fish and insect examples later in this article show [Laland & Williams 1997; Alem et al. 2016].

Animals also differ in when they rely on social information. Laland reviewed a number of strategies predicted by theoretical analyses, including "copy when uncertain", "copy the majority" and "copy if better", and considered the empirical evidence for each from both the animal and the human literature [Laland 2004]. He suggested that reliance on social learning may be organised hierarchically. Animals turn to it when unlearned and individually learned strategies prove ineffective, but before they resort to innovating [Laland 2004]. "Copy the majority", or conformity, has turned out to be especially important, because it can keep a group's tradition stable even when an equally good alternative is available [Aplin et al. 2015; Whiten et al. 2005].

Japanese Macaques and the "Hundredth Monkey" Myth

The best-known early example of an animal tradition comes from a troop of Japanese macaques (Macaca fuscata) on the small Japanese island of Kōshima [Kawai 1965]. Researchers provisioned the monkeys with sweet potatoes and wheat on the beach, which made them easier to observe [Kawai 1965; Amundson 1985]. In September 1953 a young female named Imo, then about one and a half years old, began washing sand off sweet potatoes in water, and the behaviour gradually spread to other members of the troop [Kawai 1965]. Masao Kawai recorded when each individual acquired the habit, and used the cautious term "pre-cultural" for such behaviour [Kawai 1965; Amundson 1985].

The pattern of spread was revealing. It passed first among Imo's young playmates and to her mother, so that in an unusual reversal older animals learned from younger ones [Amundson 1985]. By March 1958, 2 of 11 monkeys older than seven had learned to wash potatoes, compared with 15 of 19 monkeys aged between two and seven [Kawai 1965; Amundson 1985]. By 1962, 36 of 49 monkeys had the habit [Kawai 1965; Amundson 1985]. After 1958, as the young innovators grew up, the habit was passed mainly from mothers to their offspring, and Kawai distinguished this later period of "pre-cultural propagation" from the earlier period of "individual propagation" [Amundson 1985]. Imo is also credited with a second innovation, separating grains of wheat from sand by throwing handfuls into the water [Kawai 1965].

Kōshima later became the source of a popular myth. In his 1979 book Lifetide, Lyall Watson described a "hundredth monkey" effect: once a critical number of monkeys had learned potato washing in the autumn of 1958, almost the entire troop supposedly acquired it at once, and the habit was said to have appeared spontaneously on other islands and on the mainland [Amundson 1985]. The philosopher Ron Amundson checked this story against the scientific sources Watson cited and found no support for it [Amundson 1985]. The troop numbered 20 animals in 1952 and 59 by 1962, so there was never a hundredth monkey. Kawai's paper reported no sudden learning event in 1958, and only two monkeys learned potato washing that year [Amundson 1985]. Reports of the behaviour elsewhere described only a few individuals, not colonies that had suddenly adopted it [Amundson 1985]. The real Kōshima story is a gradual, well-documented spread along social and family lines, which is interesting in its own right.

The case has scientific caveats too. Galef questioned whether potato washing spread by imitation at all, and used it as one of his main examples when arguing against treating animal traditions as homologous to human culture [Galef 1992]. The behaviour also depended entirely on human provisioning. Kōshima is therefore best understood as an early and influential record of a novel behaviour spreading through a group, not as proof of any particular mechanism of learning [Kawai 1965; Galef 1992].

Birds: From Milk Bottles to Wild Experiments

In 1921, birds described as tits were seen prising open the tops of milk bottles left on doorsteps in Swaythling, near Southampton, and drinking the milk [Fisher & Hinde 1949]. James Fisher and Robert Hinde analysed records gathered through a British Trust for Ornithology enquiry and showed that the habit had since spread widely in England and to parts of Wales, Scotland and Ireland, with records involving at least eleven bird species, mainly blue tits and great tits [Fisher & Hinde 1949]. The records suggested that the habit was started by relatively few individual birds and that most others learned it from them in some way [Fisher & Hinde 1949]. Because many records came from places far from any earlier sighting, the habit also appeared to have arisen independently many times [Fisher & Hinde 1949]. Using captive black-capped chickadees (Poecile atricapillus), David Sherry and Bennett Galef later argued that the habit could have spread through simpler forms of social learning than imitation, such as birds encountering bottles that others had already opened [Sherry & Galef 1984].

The milk-bottle records were observational, so the mechanism of spread could not be tested directly. Nearly seventy years later, Lucy Aplin and colleagues ran the experiment in a wild population of great tits (Parus major) in Wytham Woods, Oxfordshire [Aplin et al. 2015]. In five local sub-populations they caught two males and trained them to open a puzzle box by sliding its door in one of two directions, left or right. Both solutions gave the same food reward. In three control sub-populations, males were caught but not trained [Aplin et al. 2015].

From only two trained birds in each sub-population, the new skill spread rapidly through social network ties to reach an average of 75% of individuals. In total, 414 birds learned to open the boxes and recorded 57,909 solutions across all replicates [Aplin et al. 2015]. Each sub-population was heavily biased towards the technique that had originally been introduced. These local traditions remained stable over two generations despite high population turnover [Aplin et al. 2015]. The study also found a strong effect of conformity. Birds disproportionately adopted the most common local variant when first learning, continued to favour social over personal information, and birds that moved into an area where the other variant was common tended to switch to it [Aplin et al. 2015]. The authors described this as the first experimental demonstration of conformity in a wild non-primate, and of cultural norms in foraging techniques in any wild animal [Aplin et al. 2015].

Birdsong, in which young birds learn their species' song from adult tutors and local dialects can form, is another major example of culture in birds. It is covered in this series' article on vocal learning in songbirds.

Great Ape Cultures

Chimpanzees (Pan troglodytes) were the first animals for which researchers described not just one tradition but a whole suite of them. Andrew Whiten and colleagues, together with researchers from the major long-term field sites, combined data from the seven longest-running chimpanzee studies across Africa, which together amounted to 151 years of observation [Whiten et al. 1999]. They identified 39 behaviour patterns, including forms of tool use, grooming and courtship, that were customary or habitual in some communities but absent in others, where ecological explanations for the absence had been ruled out [Whiten et al. 1999]. The combined repertoire of each community was itself distinctive, which the authors noted is characteristic of human cultures but had not previously been recognised in any other species [Whiten et al. 1999].

A similar ethnographic analysis was then carried out for orangutans. Carel van Schaik and colleagues documented geographic variation in orangutan behaviour and tested predictions of a cultural interpretation [van Schaik et al. 2003]. Cultural differences between sites increased with the geographic distance between them. Sites with more opportunities for social learning had larger local repertoires, and habitat had no effect on the content of the cultures [van Schaik et al. 2003]. The authors concluded that great-ape cultures exist and may have done so for at least 14 million years [van Schaik et al. 2003].

The ethnographic method has a weakness: geographic differences could still reflect undetected genetic or environmental factors. Whiten, Victoria Horner and Frans de Waal therefore tested transmission experimentally in captive chimpanzees [Whiten et al. 2005]. They trained a high-ranking female from each of two groups to use a different technique to obtain food from the same apparatus. One female learned to poke a blocking device so that the food rolled out at the back, and the other to lift it so that the food fell forwards [Whiten et al. 2005]. When each female was returned to her group, all but two of 32 chimpanzees mastered the technique used by their local expert, while none did so in a third group that had no trained expert [Whiten et al. 2005]. Some chimpanzees that discovered the alternative method went on to match the technique most common among their companions. This conformity bias had previously been regarded as a hallmark of human culture [Whiten et al. 2005]. Corvid tool use, which raises related questions about innovation and social learning in birds, is discussed in a separate article in this series.

Cultures in the Sea: Whales, Dolphins and Fish

Rendell and Whitehead's review of culture in whales and dolphins argued that there is good evidence for cultural transmission in several cetacean species [Rendell & Whitehead 2001]. They noted that only the bottlenose dolphin (Tursiops) had then been shown experimentally to have sophisticated social learning abilities, including vocal and motor imitation, and that there was observational evidence for imitation and teaching in killer whales (Orcinus orca) [Rendell & Whitehead 2001]. They described the complex and stable vocal and behavioural cultures of sympatric groups of killer whales as having no parallel outside humans [Rendell & Whitehead 2001]. Culture can also be conservative. Southern resident killer whales persist in their specialisation on Chinook salmon (Oncorhynchus tshawytscha), an example of cultural conservatism with direct conservation implications [Brakes et al. 2019]. In sperm whales (Physeter macrocephalus) in the eastern tropical Pacific, cultural transmission of vocal patterns has produced distinct vocal clans [Brakes et al. 2019].

Male humpback whales (Megaptera novaeangliae) sing a long, stereotyped song that changes over time, and all males in a population conform to the current version [Garland et al. 2011]. Michael Noad and colleagues recorded a radical change off the east coast of Australia, where the Pacific population's song was replaced rapidly and completely by the song of the west-coast population from the Indian Ocean [Noad et al. 2000]. The change was apparently triggered by the arrival of only a small number of "foreign" singers [Noad et al. 2000]. Ellen Garland and colleagues then showed that this was not a one-off. Over an 11-year period, multiple song types spread rapidly and repeatedly eastwards, in one direction, through populations in the western and central South Pacific, like "cultural ripples" [Garland et al. 2011]. This was the first documentation of repeated, dynamic cultural change across multiple populations at such a large geographic scale [Garland et al. 2011].

Humpbacks also have foraging traditions. Jenny Allen and colleagues used network-based diffusion analysis to trace the spread of lobtail feeding, a foraging innovation in which a whale strikes the water surface with its tail, through a humpback population over 27 years [Allen et al. 2013]. Models that included social transmission were 6 to 23 orders of magnitude better supported than models without it. The distribution of sand lance, a prey fish, also helped predict when whales acquired the behaviour [Allen et al. 2013].

Fish provided some of the earliest experimental evidence for animal traditions. French grunts (Haemulon flavolineatum) on coral reefs have social traditions of daytime schooling sites and twilight migration routes [Helfman & Schultz 1984]. Gene Helfman and Eric Schultz moved individual fish between populations. Transplanted fish that could follow residents at their new site learned the residents' routes and schooling sites and continued to use them, whereas control fish without that opportunity did not [Helfman & Schultz 1984]. In the laboratory, Laland and Kerry Williams trained guppies (Poecilia reticulata) to take one of two equally good routes to food, then gradually replaced the trained founders with untrained fish. Three days after all the founders had been removed, the groups still strongly preferred their founders' route [Laland & Williams 1997]. The authors concluded that arbitrary behavioural alternatives can be maintained as traditions in shoaling fish through very simple social mechanisms [Laland & Williams 1997].

Small Brains and Long Journeys: Insects and Ungulates

Culture has usually been studied in large-brained animals, but experiments with bumblebees (Bombus terrestris) challenged that assumption. Sylvain Alem and colleagues presented bees with a food reward that was out of reach and could be obtained only by pulling a string [Alem et al. 2016]. Only a small minority of bees solved the task spontaneously, but most could learn it when trained step by step, and naïve bees learned it by watching a trained demonstrator [Alem et al. 2016]. In cultural diffusion experiments, the skill spread from a single knowledgeable bee to most of a colony's foragers. It passed through several successive "generations" of learners, so the skill could outlast the bees that first knew it [Alem et al. 2016]. The authors concluded that a basic toolkit of associative and motor learning is enough for unusual skills to spread culturally, without sophisticated cognition [Alem et al. 2016].

At the other extreme of scale, culture may shape the migrations of large mammals. Ungulate migrations have long been assumed to depend on learned knowledge of where good forage appears through the seasons, but this had not been tested directly [Jesmer et al. 2018]. Brett Jesmer and colleagues compared bighorn sheep (Ovis canadensis) and moose (Alces alces) translocated into unfamiliar habitats with historical populations that had persisted for hundreds of years [Jesmer et al. 2018]. Animals from historical populations were largely migratory, but translocated animals initially were not. Over several decades, translocated populations learned to "surf" green waves of new plant growth and became more likely to migrate [Jesmer et al. 2018]. The authors concluded that learning and cultural transmission are the primary mechanisms by which ungulate migrations develop, and that losing a migration would erase generations of knowledge about where high-quality forage is found [Jesmer et al. 2018]. The navigation mechanisms that migratory animals use are covered in this series' article on animal migration.

Culture and Conservation

Conservation has traditionally been guided by genetic, ecological and demographic indicators of risk, such as population size and genetically defined units [Brakes et al. 2021]. A growing group of researchers argues that culture should be added to this toolkit, because social learning can influence population viability, help or hinder responses to human-caused change, and produce groups with distinct, socially learnt behavioural strategies [Brakes et al. 2021]. Social learning can spread helpful behaviour quickly, such as exploiting a new food source, but it can also spread behaviour that increases conflict with people, such as sperm whales learning to remove fish from longlines [Brakes et al. 2019].

This thinking has reached international policy. Under the Convention on the Conservation of Migratory Species of Wild Animals (CMS), a 2014 resolution formally recognised the importance of social learning and culture for the conservation of some highly social species, following a consultation focused on whales and dolphins [Brakes et al. 2019]. An expert group set up by the CMS Scientific Council concluded that social learning is relevant to conservation across a wide range of vertebrates, including birds, fishes and many marine and terrestrial mammals [Brakes et al. 2019]. After a cross-taxa workshop held in Parma, Italy, in 2018, the group made several recommendations. These included conserving individuals that are critical repositories of social knowledge, improving reintroduction schemes through strategic management of social knowledge, and systematically cataloguing cultural diversity [Brakes et al. 2019].

Evidence that human activity erodes animal culture is now emerging. Hjalmar Kühl and colleagues assembled data on 31 behaviours from 144 chimpanzee communities across Africa [Kühl et al. 2019]. In areas of high human impact, the mean probability of these behaviours occurring was reduced by 88% compared with low-impact areas, whichever way the behaviours were grouped or categorised [Kühl et al. 2019]. The authors concluded that human impact affects not only population numbers and genetic diversity but also how animals behave, and supported integrating "culturally significant units" into wildlife conservation [Kühl et al. 2019].

The same principles have practical applications. Translocated or reintroduced animals may lack knowledge that wild-born animals acquire socially. Translocated bighorn sheep and moose took decades to develop migrations [Jesmer et al. 2018], and captive-bred whooping cranes have been guided on their first migration by ultralight aircraft because the birds learn migratory routes socially [Brakes et al. 2019]. Older, experienced individuals can hold knowledge that younger animals depend on. The experience of African elephant matriarchs, for example, has been linked to higher fertility among younger females in their groups, which suggests that such individuals deserve particular protection [Brakes et al. 2019]. Where populations are divided into cultural units with different needs, such as sperm whale vocal clans whose feeding success differs during El Niño and La Niña cycles, a single management plan for the whole population may not fit every group [Brakes et al. 2019]. The lesson from the research on animal culture is that what an animal population knows, and how that knowledge is passed on, can matter for its survival alongside its numbers and genes.

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