« Prev Next »
Cognition is the ability to interpret and connect information that is perceived in the world and to then apply this personal knowledge adaptively to future situations and problems (Cheney & Seyfarth, 1990). Importantly, this allows the animal to improve their fitness. All animals have to negotiate their environment to allow them to forage for food, avoid predation and find mates. Primates stand out among other taxa for their flexibility in how they deal with the world around them. They inhabit both complex physical and social worlds, which have each been posited as the major selective pressures driving the advancement of primate brain size and, by extension, their cognitive abilities (Byrne, 2000; Reader et al., 2011); accordingly we first describe their understanding of their physical environment and then go on to discuss social cognition.
Primate Cognition about the Physical World
Cognitive mapping
Across the world, primates have to master an array of environmental topographies, negotiate weather extremes, and move about their territory safely and efficiently. Within their home range, primates need to understand and recall the features that lie within it, which requires both cognitive mapping skills and a flexible memory. Importantly, cognitive mapping allows primates to remember not just where physical landmarks are (e.g., trees) but also salient and changing features (when that tree will bear fruit). When navigating their environment, primates do not travel aimlessly, but move about it in a directed manner. Monkeys (e.g. Hylobates lar and Cebus apella) and apes (e.g. Pan troglodytes and Gorilla gorilla)will take the most efficient routes, maximizing the available food that they pass (Asensio, et al., 2011; Bates & Byrne, 2009; Janson, 1998; Vedder, 1984), to reach preferred fruiting trees (Ban et al., 2014). Cognitive mapping is essential for increasing fitness, because in dense environments vision is often extremely limited,and fruiting trees (or other valuable resources) may not be easily visible; planning travel paths thus reduces energy expenditure and search costs. Of course, the foci of individual interest may vary, even within species, revealing flexibility in primate decision-making. For instance, chimpanzee females are more likely to plan routes following paths that will lead them to food sources whereas males appear more concerned with monitoring the border of their territory (Bates & Byrne, 2009).
Memory and future planning
The memory of primates has been studied fairly extensively, revealing, for example, that apes are able to recall locations of items after delays of up to 16 hours (Menzel, 1999) and replicate novel actions demonstrated to them over 24 hours previously (Hopper, 2010). Furthermore, like humans, monkeys (Macaca mulatta) and apes (Pan troglodytes) are able to recall serial lists of images (Inoue & Matsuzawa, 2007; Sands & Wright, 1980). Indeed, the working memory capacities of captive chimpanzees, in some cases, may outdo the performance of humans (Inoue & Matsuzawa, 2007; but see Cook & Wilson, 2010). Primates' memory also allows for future planning. Chimpanzees, for example, are able to select specific tools and save them to solve particular tasks at a later time (Mulcahy & Call, 2006a) and, when foraging for fruits in their environment, monkeys (Lophocebus albigena)have been reported to apply knowledge of the past days' temperatures to determine on which trees ripe fruit will now be likely found (Janmaat et al., 2006). This flexibility may require mental representation and both ape (Pan troglodytes) and monkey (Macaca fascicularis, Papio anubis and Saimiri sciureus) species are able to apply Roman numerals to specific quantities in ways comparable with young children, and use such numerals for simple arithmetic (Boysen & Berntson, 1989; Olthof, et al., 1997; Schmitt & Fischer, 2011).
Tool-use behavior and causal understanding
The sensory-motor cognition of primates is highlighted by their dexterous use of tools. Both ape and monkey species use tools to eat otherwise inaccessible foods (Ottoni & Mannu, 2001; Whiten, 2011). The ability of primates to manufacture tools to specific requirements demonstrates an understanding of causal relations and physical properties (causal understanding). White bearded capuchin monkeys (Cebus libidinosus), for example, select substrates of specific weight and material to use as hammers when cracking nuts (Visalberghi et al., 2008). This skill appears to be learnt during the monkey's development, with young brown capuchin monkeys (C. apella) showing indiscriminate and ineffectual preferences for tool material, and their skill increasing with age (Pouydebat et al., 2006). This learnt skill highlights the interplay of the material and social world that primates negotiate; individuals learn about the causal relations of their physical environment from both personal interaction and social observation. More formal tests of causal understanding with apes in captivity report that all four apes species show a clear understanding of causal relations (Mulcahy & Call, 2006b, but see Horner & Whiten, 2007), using tools flexibly to negotiate food around obstacles.
Social Cognition
The social world that primates inhabit adds another dimension to their cognitive demands. Tests of self-recognition have led to the hypothesis that some primate species have an understanding of theory of mind (Gallup, 1970), which further enables them to monitor their social world and their relation to it. Research reveals that primates can recognize and distinguish individuals (Parr et al., 2000), retain knowledge about social relations (Byrne & Whiten, 1988), and that chimpanzees (Pan troglodytes, Hare et al., 2001), but not capuchin monkeys (Cebus apella, Hare et al., 2003), recognize what others know. This knowledge of fellow members of their social group enables primates to determine who to associate with, cooperate with, and potentially learn from, and how to manipulate individuals or situations (Brosnan & Hopper, 2013).
Cooperation and prosocial behaviour
Primates cooperate on tasks as diverse as group hunting, territory defence, and rank acquisition through alliances, and, in some cases, showing quite complex behaviours (e.g., Boesch 1994). In some tasks, at least, non-human primates reach outcomes equivalent to those of humans (e.g. Brosnan et al., 2011). Primates are sensitive to task demands, for instance cooperating at a higher rate when rewards cannot easily be dominated by another individual (de Waal & Davis, 2006). Intriguingly, species which routinely cooperate with non-kin are also more likely to respond negatively to inequity, indicating that cooperation and an abilityto recognise inequity may have co-evolved in some species (Brosnan, 2011). Primates also appear to engage in only limited reciprocity; although reciprocity is seen in long-term analyses of wild populations (Gomes et al., 2008; Gomes & Boesch, 2009), short-term laboratory experiments have found little evidence for such behaviour (Melis et al., 2008; but see Melis et al., 2011). This may indicate that most reciprocity is based on longer-term relationships rather than immediate contingency.
While cooperation is common, prosocial behaviour is more rare. There is little evidence in apes that individuals change their behaviour to bring a partner food (e.g. Silk et al., 2005; but see Horner et al., 2011), although several monkey species do so (e.g. de Waal et al., 2008; Burkart et al., 2007; Massen et al., 2010), even in cases in which being prosocial actually results in inequity towards the provider (Brosnan et al., 2010). On the other hand, even among chimpanzees, behaviours which help a partner are seen outside of the food context (e.g., helping; Warneken & Tomasello, 2006). One hypothesis is that prosocial behaviours are more common among cooperative breeders, due to the unique costs and benefits related to their interactions with each other (Blaffer-Hrdy, 2009), leading them to more actively share food with partners (Jaeggi et al., 2010).
Machiavellian and social Intelligence
Primates are able to use their skills in social cognition to their advantage by manipulating the behaviour of others. In fact, one hypothesis for primates' unusual intelligence is that cognitive skills were strongly selected because of the necessity of outsmarting rivals (Byrne & Whiten, 1988). This may be most evident in the case of deception. Deception is rarely observed, partially because it is expected to be uncommon to avoid habituation by potential targets (Cheney & Seyfarth 1990). However, a field experiment with capuchin monkeys (Cebus apella) has demonstrated tactical deception (Wheeler, 2009). In cases of artificial provisioning, lower-ranking monkeys are more likely to give alarm calls in contested situations in which the departure of the dominant could result in more food for the caller. Thus the absence of an extensive literature on deception may equally be due to an absence of deception, or to the challenges of demonstrating what is by necessity a rare behaviour.
Social learning
The ability of primates to learn socially from one another, taking advantage of the knowledge of others, blurs the distinction between how they learn about their physical and social worlds (van Schaik & Burkart, 2011). The major importance of social learning is that it facilitates the transfer of information between individuals without the need for genetic inheritance and can bypass potentially costly and time-consuming trial-and-error learning. In humans, this has allowed for the emergence of our diverse cultural world. Social learning has been reported for many primate species but do they have cultures like us? Primates do indeed show evidence for socially-learned, behavioural traditions. Although undoubtedly not as rich as human culture, certain wild primate communities sustain multiple site-specific behaviours analogous to our culture with such traditions identified in ape (Pan troglodytes, Pongo pygmaeus) and monkey (Macaca fuscata, Cebus capucinus and Ateles geoffroyi) species in the wild (Santorelli et al., 2011).
There is clearly a marked difference, however, between human culture and the behavioural traditions of primates, and what underlies this contrast is currently a topic of much debate. Cumulative culture has been proposed to describe the underlying mechanism that has allowed for the development of our complex technologies. Without the ability for imitation or teaching, researchers argue, primates may not be capable of cumulative learning because the complex information required for such intricate behaviours cannot be transmitted faithfully (Dean et al., 2014; Tomasello, 1999). Experimental studies with humans, however, reveal that teaching and imitation are not prerequisite for cumulative culture (Caldwell & Millen, 2009; Caldwell et al., 2012). Given this, along with the mounting evidence that primates are able to copy even complex tool-use behaviours from observing others (Price et al., 2009), what can explain the relative paucity of the cultural worlds of our closest-living relatives, especially for the chimpanzee? It may well be that the very ability of chimpanzees to copy others leads to their limited ability to build on the knowledge of previous generations. After learning a specific method from observations of others, chimpanzees appear to become entrenched and unable to transition to a new behaviour, even if the introduced method is more efficient (Hopper et al., 2011). Although seemingly a limitation of their learning capacities, such as conformity and conservatism may enable chimpanzees to maintain strong social bonds and potentially avoid risks in the wild. Thus, the key ability here is not just in copying others, but determining when to do so (Rendell et al., 2011).
Conclusions
We are still learning much about the cognitive capacities of primates, informing us not just about our own evolutionary past and the capabilities of our common ancestor, but also about the specific and unique adaptations each species has for its own physical and social world. The cognitive capacities of primates should not just be used as a baseline for comparison to human capabilities, but also studied in their own right in order to better understand the cognitive repertoire of each species and the effects of differing environments on the evolution of cognition.
Glossary
causal understanding: The ability to "understand not just that two events are associated with one another in space and time, but also that there is some ‘mediating force' that binds the two events to one another which may be used to predict or control those events" (Visalberghi & Tomasello, 1998, p.189).
cognitive mapping: "The representation embodied in a cognitive map is typically assumed to encode distances and directions and to enable mental operations of them" (Shettleworth, 1998, p.296) allowing animals to calculate the optimum routes from point A to point B.
conservatism: Mastery of a skill inhibits further exploration to new alternative options or behavioural strategies which may be more efficient
cooperation: Two or more individuals increase their direct fitness more by working together than individually (Brosnan, Salwiczek & Bshary, 2010).
cooperative breeders: Social system in which young are cared for by both parents and, often, their mature offspring.
cumulative culture: The process by which generations build upon the knowledge of previous ones creating increasingly complex artefacts and technologies through the accumulation of design — the so-called "ratchet effect" (Tomasello, 1999).
deception: The provisioning of false information which affects another individual's behaviour in favour of the deceiver. While this may occur without intention on the part of the deceiver, resulting in functional, or tactical, deception, individuals may also do so intentionally.
fission-fusion: In which a group of individuals breaks ups and reforms over the course of a day or week meaning that each party size represents a subset of total group size.
fitness: The ability to survive and successfully reproduce (e.g., evolutionary fitness)
home range: The territory which a primate, or group of primates, occupies. Note, primates move about their territory but may only travel within small subsections each day. Furthermore, the degree to which a primates' home range overlaps with conspecifics and different primate species is affected not just by the specific primate but also by environmental and space pressures (e.g., food availability and deforestation).
imitation: Copying the exact behaviours demonstrated by another. Compare with ‘emulation' in which an individual merely replicates the goal or end-state of a novel behaviour performed by others.
inequity: A situation in which unequal rewards are received. The behavioural response studied is ‘inequity aversion' vis-à-vis a sense of unfairness (see Brosnan, 2006, for further discussion).
prosocial behaviour: Behaviour which results in a benefit to another individual.
teaching: "An individual actor A can be said to teach if it modifies its behaviour only in the presence of a naive observer, B, at some cost or at least without obtaining an immediate benefit for itself. A's behaviour thereby encourages or punishes B's behaviour, or provides B with experience, or sets an example for B. As a result, B acquires knowledge or learns a skills earlier in life or more rapidly or efficiently than it might otherwise do, or that it would not learn at all" (Caro & Hauser, 1992, p. 153).
theory of mind: The attribution of mental states such as beliefs, thoughts, desires and intentions to oneself and others. See Heyes (1998) for a detailed discussion about primate understanding of theory of mind.
traditions: "enduring behaviour patterns shared among members of a group that depend to a measurable degree on social contributions to individual learning, resulting in shared practices among members of a group" (Fragaszy & Perry, 2003, p.3)
working memory: The short-term retention of information which may sometimes incorporate elements of information processing.
References and Recommended Reading
Recommended Reading:
Byrne, R. W. The Thinking Ape: The Evolutionary Origins of Intelligence. Oxford, UK: Oxford University Press (1995).
de Waal, F. B. M. & Ferrari, P. F. The Primate Mind: Built to Connect with Other Minds. Cambridge, MA: Harvard University Press (2012).
Maestripieri, D. Primate Psychology. Cambridge, MA: Harvard University Press (2005).
Tomasello, M. & Call, J. Primate Cognition. Oxford, UK: Oxford University Press (1997).
References:
Asensio, N., Brockelman, W. et al. Gibbon travel paths are goal oriented. Animal Cognition 14, 395-405 (2011).
Ban, S., Boesch, C. & Janmaat, K. L. Taï chimpanzees anticipate revisiting high-valued fruit trees from further distances. Animal Cognition (EPUB 2014) doi:10.1007/s10071-014-0771-y.
Bates, L. A. & Byrne, R. W. Sex differences in the movement of free-ranging chimpanzees (Pan troglodytes schweinfurthii). Behavioral Ecology & Sociobiology 64, 247-255 (2009).
Blaffer-Hrdy, S. Mothers and Others: The Evolutionary Origins of Mutual Understanding. Cambridge, MA: Belknap Press of Harvard University Press (2009).
Boesch, C. Cooperative hunting in wild chimpanzees. Animal Behavior 48, 653-667 (1994).
Boysen, S. T. & Berntson, G. G. Numerical Competence in a Chimpanzee (Pan troglodytes). Journal of Comparative Psychology 103, 23-31 (1989).
Brosnan, S. F. Nonhuman species' reactions to inequity and their implications for fairness. Social Justice Research 19, 153-185 (2006).
Brosnan, S. F. A hypothesis of the co-evolution of inequity and cooperation. Frontiers in Decision Neuroscience 5, 43 (2011).
Brosnan, S. F. & Bshary, R. Cooperation and deception: from evolution to mechanisms. Philosophical Transactions of the Royal Society London B 365, 2593-2598 (2010).
Brosnan, S. F. & Hopper, L. M. Cooperation, behavioral diversity and inequity responses. In M. Banaji & S. Gelman (Eds.) Navigating the Social World: What Infants, Children, and Other Species Can Teach Us. (pp. 371-376). New York: Oxford University Press (2013).
Brosnan, S. F., Houser, D. et al. Competing demands of prosociality and equity in monkeys. Evolution & Human Behavior 31, 279-288 (2010).
Brosnan, S. F., Parrish, A. R. et al. Responses to the assurance game in monkeys, apes, and humans using equivalent procedures. Proceedings of the National Academy of Sciences 108, 3442-3447 (2011).
Burkart, J. M., Fehr, E. et al. Other-regarding preferences in a non-human primate: Common marmosets provision food altruistically. Proceedings of the National Academy of Sciences 104, 19762-19766 (2007).
Byrne, R. W. Evolution of primate cognition. Cognitive Science 24, 543-570 (2000).
Byrne, R. W. & Whiten, A. Machiavellian Intelligence: Social Expertise and the Evolution of Intellect in Monkeys, Apes, and Humans. Oxford, UK: Clarendon Press (1988).
Caldwell, C. A. & Millen, A. E. Social learning mechanisms and cumulative cultural evolution: Is imitation necessary? Psychological Science 20, 1478-1483 (2009).
Caldwell, C. A., Schillinger, K., Evans, C. L. & Hopper, L. M. End state copying by humans (Homo sapiens): Implications for a comparative perspective on cumulative culture. Journal of Comparative Psychology 126, 161-169 (2012).
Caro, T. M. & Hauser, M. D. Is there teaching in nonhuman animals? The Quarterly Review of Biology 67, 151-174 (1992).
Cheney, D. L. & Seyfarth, R. M. How Monkeys See the World: Inside the Mind of Another Species. Chicago, IL: University of Chicago Press (1990).
Cook, P. & Wilson, M. Do young chimpanzees have extraordinary working memory? Psychological Bulletin & Review 17, 599-600 (2010).
Dean, L. G., Vale, G. L. et al. Human cumulative culture: a comparative perspective. Biological Reviews 89, 284-301 (2014).
de Waal, F. B. M. & Davis, J. M. Capuchin cognitive ecology: Cooperation based on projected returns. Neuropsychologia 1492, 1-8 (2002).
de Waal, F. B. M., Leimgruber, K.& Greenberg, A. Giving is self-rewarding for monkeys. Proceedings of the National Academy of Sciences 105, 13685-13689 (2008).
Gallup, G. G., Jr. Chimpanzees: Self-recognition. Science 167, 86-87 (1970).
Gomes, C. M. & Boesch, C. Wild chimpanzees exchange meat for sex on a long-term basis. PLoS ONE 4, e5116 (2009).
Gomes, C. M., Mundry, R. & Boesch, C. Long-term reciprocation of grooming in wild West African chimpanzees. Proceedings of the Royal Society of London B. 276, 609-706 (2008).
Hare, B., Addessi, E. et al. Do capuchin monkeys, Cebus apella, know what conspecifics do and do not see? Animal Behaviour 65, 131-142 (2003).
Hare, B., Call, J. & Tomasello, M. Do chimpanzees know what conspecifics know? Animal Behaviour 61, 139-151 (2001).
Heyes, C. M. Theory of mind in nonhuman primates. Behavioral and Brain Sciences 21, 101-148 (1998).
Hopper, L. M. Deferred imitation in children and apes: Children imitate after a delay, but can apes ape in a similar fashion? The Psychologist 23, 2-5 (2010).
Hopper, L.M., Schapiro, S. J. et al. Chimpanzees' socially maintained food preferences indicate both conservatism and conformity. Animal Behaviour 81, 1195-1202 (2011).
Horner, V., Carter, J.D., Suchak, M., & de Waal, F.B.M. Spontaneous prosocial choice by chimpanzees. Proceedings of the National Academy of Sciences 108, 13847-13851 (2011).
Horner, V. & Whiten, A. Learning from others' mistakes? Limits on understanding a trap-tube task by young chimpanzees (Pan troglodytes) and children (Homo sapiens). Journal of Comparative Psychology 121, 12-21(2007).
Inoue, S. & Matsuzawa, T. Working memory of numerals in chimpanzees. Current Biology 17, R1004-R1005 (2007).
Jaeggi, A. V., Burkart, J. M.& Van Schaik, C. P. On the psychology of cooperation in humans and other primates: combining the natural history and experimental evidence of prosociality. Philosophical Transactions of the Royal Society of London B, 365, 2723-2735 (2010).
Janmaat, K. R. L., Byrne, R. W., & Zuberbühler, K. Primates take weather into account when searching for fruits. Current Biology 16,1232-1237 (2006).
Janson, C. H. Experimental evidence for spatial memory in foraging wild capuchin monkeys, Cebusapella. Animal Behaviour 55, 1229-1243 (1998).
Massen, J. J. M., van den Berg, L. M. et al. Generous leaders and selfish underdogs: Pro-sociality in despotic macaques.PLoS ONE 5, e9734 (2010).
Melis, A. P., Hare, B. & Tomasello, M. Do chimpanzees reciprocate received favours? Animal Behavior 76, 951-962 (2008).
Melis, A. P., Warneken, F. et al. Chimpanzees help conspecifics obtain food and non-food items. Proceedings of the Royal Society B 278, 1405-1413 (2011).
Menzel, C. R. Unprompted recall and reported of hidden objects by a chimpanzee (Pan troglodytes) after extended delays. Journal of Comparative Psychology 113, 426-434 (1999).
Mulcahy, N. J. & Call, J. Apes save tools for future use. Science 312, 1038-1040 (2006a).
Mulcahy, N. J. & Call, J. How great apes perform on a modified trap-tube task. Animal Cognition 9, 193-199 (2006b).
Olthof, A., Iden, C. M. & Roberts, W. A. Judgments of ordinality and summation of number symbols by squirrel monkeys (Saimiri sciureus). Journal of Experimental Psychology 23, 325-339 (1997).
Ottoni, E. B. & Mannu, M. Semifree-ranging Tufted capuchins (Cebus apella) spontaneously use tools to crack open nuts. International Journal of Primatology, 22, 347-358(2001).
Parr, L. A., Winslow, J. T. et al. Recognizing facial cues: individual discrimination by chimpanzees (Pan troglodytes) and rhesus monkeys (Macaca mulatta). Journal of Comparative Psychology 114, 47-60 (2000).
Pouydebat, E., Gorce, P. et al. Substrate optimization in nut cracking by capuchin monkeys (Cebus apella). American Journal of Primatology 68, 1017-1024 (2006).
Price, E. E., Lambeth, S. P. et al. A potent effect of observational learning on chimpanzee tool construction. Proceedings of the Royal Society B 276, 3377-3383 (2009).
Reader, S. M., Hager, Y. & Laland, K. N. The evolution of primate general and cultural intelligence. Philosophical Transactions of the Royal Society B 366, 1017-1027 (2011).
Rendell, L., Fogarty, L. et al. Cognitive culture: theoretical and empirical insights into social learning strategies. Trends in Cognitive Sciences 15, 68-76 (2011).
Sands, S. F. & Wright, A. A. Primate memory: retention of serial list items by a rhesus monkey. Science 209, 938-940 (1980).
Santorelli, C. J., Schaffner, C. M. et al. Traditions in Spider Monkeys Are Biased towards the Social Domain. PLoS ONE 6, e16863 (2011).
Schmitt, V. & Fischer, J. Representational format determines numerical competence in monkeys. Nature Communication 2, 257 (2011).
Shettleworth, S. J. Cognition, Evolution and Behaviour. Oxford, UK: Oxford University Press (1998).
Silk, J. B., Brosnan, S. F. et al. Chimpanzees are indifferent to the welfare of unrelated group members. Nature 437, 1357-1359 (2005).
Tomasello, M. The Cultural Origins of Human Cognition. Cambridge, MA: Harvard University Press (1999).
vanSchaik, C. P. & Burkart, J. M. Social learning and evolution: the cultural intelligence hypothesis. Philosophical Transactions of the Royal Society B 366, 1008-1016 (2011).
Vedder, A. L. Movement patterns of a group of free-ranging mountain gorillas (Gorilla gorillaberingei) and their relation to food availability. American Journal of Primatology 7, 73-88 (1984).
Visalberghi, E., Addessi, E. et al. Selection of effective stone tools by wild bearded capuchin monkeys (Cebus libidinosus). Current Biology 19, 213-217 (2008).
Visalberghi, E., & Tomasello, M. Primate causal understanding in the physical and psychological domains. Behavioural Processes 42, 189-203 (1998).
Warneken, F. & Tomasello, M. Altruistic helping in human infants and young chimpanzees. Science 311, 1301-1303 (2006).
Wheeler, B. Monkeys crying wolf? Tufted capuchin monkeys use anti-predator calls to usurp resources from conspecifics. Proceedings of the Royal Society B 276, 3013-3018 (2009).
Whiten, A. The scope of culture in chimpanzees, humans and ancestral apes. Philosophical Transactions of the Royal Society B 366, 997-1007 (2011).
