Monkey Behavior Explained: Mimus the Chimpanzee and the Story by Vladimir Durov

Monkey behavior spans tool use, complex social politics, emotional lives, and rich communication — behaviors that often look strikingly human. Across great apes like chimpanzees and gorillas and monkeys such as macaques, capuchins, and baboons, primates solve problems, form alliances, grieve their dead, and learn throughout life. This page explains what monkeys do and why, drawing on classic observations and modern primate research.

Understanding Monkey Behavior

Monkey behavior is the full repertoire of how monkeys forage, socialize, communicate, play, and respond to stress — shaped by species, social structure, and environment. Primatologists study these behaviors to understand intelligence, emotion, and the deep similarities between monkeys and humans.

A useful starting point is the recognition that monkeys are not a single uniform group. Macaques, baboons, capuchins, vervet monkeys, spider monkeys, marmosets, and tamarins each show species-specific behavior patterns, while great apes such as chimpanzees, gorillas, orangutans, and bonobos display the most human-like cognition. Even Galen, the Roman physician who lived about one thousand eight hundred years ago, observed while studying macaques that monkeys are funny copies of humans.

Anthropomorphic Apes and Their Human-Like Traits

Anthropomorphic (or humanoid) apes — chimpanzees, gorillas, and orangutans — earn the label from the Greek "anthropos" (man) and "morphe" (form) because so much of their behavior resembles that of people. Anyone who has watched these great apes is struck by their cleverness and by gestures, expressions, and routines that mirror human conduct. The defining trait is that great apes, when needed, work out how to use objects such as sticks and stones as tools to reach a goal.

Durov's Chimpanzee Mimus: A Famous Example

The animal trainer Vladimir Leonidovich Durov kept a young chimpanzee named Mimus, whom he described in the story "Monkey Mimus" within his collection "My Animals." Durov's account captures how human-like a chimpanzee's daily behavior can appear. Two excerpts follow:

- Hello, Mimus!

- I say as I open the chimpanzee's cage in the morning.

Little furry arms wrap around my neck, and his trumpeted lips gently touch my lips. And behind me stands my wife. Mimus respectfully brings her hand to his lips and kisses it, but then feeling overtakes form, and he simply, unpretentiously, embraces her. His wife carries Mimus away in her arms..... We go to the bathroom to do our morning wash.

Mimus already feels the need for it. He can't stand dirty hands, he takes the soap himself, opens the faucet and washes himself, then puts the soap down and starts to wipe his hands with a towel. True, he has not yet gotten to washing his face, and my wife washes his face. But he doesn't resist. He even ridiculously reaches out to her face and only wrinkles and closes his eyes ....

Durov noted that Mimus reminded the household more of a human every day. When the chimpanzee needed something he expressed it precisely: he tapped a finger on the bottom of his plate when he saw a piece of apple or pear, pointed at the chain when he wanted out of the cage, and pressed the bell consciously. At the table he behaved no worse than a well-behaved five-year-old child, ate carefully with a spoon and fork, did not scatter food, and pulled his own chair to the table before dinner. He lacked only human speech, yet his intelligent, expressive eyes suggested he understood what was said around him.

Tool Use and Intelligence in Monkeys

Tool use is one of the clearest demonstrations of monkey intelligence, and it appears in both great apes and the so-called lower monkeys. Primates use sticks, stones, and improvised implements to obtain food, defend themselves, and solve problems they cannot solve by hand alone. The behaviors below are classic illustrations of that problem-solving ability.

The Chimpanzee Sultan and the Orange Experiment

The chimpanzee Sultan provided a textbook example of insight in primates. An orange was placed just out of reach in front of his cage; Sultan first tried to grab it through the bars, then struck the bars with bamboo sticks, then tried to rake the fruit closer with a single stick that proved too short. After a long struggle he discovered that one stick could be inserted into the hollow end of a thicker stick, and with this lengthened tool he pulled the orange to the bars and lifted it out by hand.

Gorillas Using Sticks to Solve Problems

A gorilla using a stick to push bait out of a tube shows an even subtler form of reasoning. To free the reward the gorilla must push it away from itself before it becomes reachable — a counter-intuitive move. That a gorilla grasps this indirect solution points to genuine problem-solving rather than trial-and-error luck.

Pavlov's Chimpanzees: Rose and Rafael

In the laboratory of Academician Ivan Petrovich Pavlov (1849–1936) lived two chimpanzees, Rose and Rafael, with Rafael solving notably complex tasks. Rafael used a long pole to climb from one raft to another, independently opened a cistern faucet, drew water into his mouth, and poured it onto a fire blocking his bait. What makes the case revealing is the emotional dimension: each success brought Rafael joy and jubilation, while failure left him despondent and hysterical, rolling on the floor like a capricious child and making pitiful sounds. These reactions show that primate intelligence is tightly bound to emotion.

Charles Darwin (1809–1882) documented similarly resourceful behavior in orangutans, which use sticks and stones to reach goals and learn to handle utensils and bedding.

Capuchin Monkey Tool Use and Problem Solving

Capuchin monkeys are among the most accomplished tool users of the New World, famous for cracking hard palm nuts with stone hammers and anvils. Wild bearded capuchins (Sapajus libidinosus) studied by Fragaszy and colleagues at Fazenda Boa Vista in Brazil select heavy stones, carry them to favored anvil sites, and place each nut carefully in a pit on the anvil before striking — strategic placement that reduces the chance the nut rolls away. This nut-cracking tradition depends on haptic perception: capuchins feel and adjust grip and force through touch, integrating tactile sensing with cognitive processing to land an effective blow. The BBC series Clever Monkeys helped popularize these behaviors, which place capuchins alongside chimpanzees in the small club of habitual stone-tool users among primates.

Social Behavior in Monkey Troops

Monkeys live in complex societies where status, alliances, and friendships determine access to food, mates, and safety. A group of monkeys is organized around dominance hierarchies, kin bonds, and shifting coalitions, and an individual's social position strongly affects its health and reproductive success. Understanding these social systems is central to understanding monkey behavior overall.

Alliance Formation and Social Bonds

Alliance formation lets monkeys gain and defend social rank that they could not achieve alone. Individuals back allies in disputes, reconcile after fights, and trade support for grooming, building coalitions that can override raw physical strength. In species such as baboons and macaques, the certainty of one's rank — how clearly settled the hierarchy is — shapes stress levels, with ambiguous or contested positions often the most stressful.

Close Social Partnerships and Affiliative Networks

Close affiliative partnerships, expressed mainly through grooming, are the connective tissue of a monkey troop. Allogrooming removes parasites but, more importantly, cements bonds, signals affection, and reduces tension, and monkeys invest the most grooming in their strongest partners. Research consistently links strong social connections to better health outcomes and longer survival, mirroring findings on social support in humans. Bonobos take affiliation furthest, maintaining notably peaceful, female-centered social networks in which tension is often defused through contact rather than aggression.

Aggression and Social Competence

Aggression in monkey troops is not simply a failure of order but a tool for negotiating status and resources. Socially competent individuals deploy aggression selectively, balance it with reconciliation, and read the troop's tensions accurately. Male baboons illustrate the cost side of this equation: maintaining and contesting high rank in a baboon hierarchy is physiologically taxing, and the stress of social competition leaves measurable marks on health.

Adult Play in Primates

Play is a fundamental primate behavior that persists well into adulthood in many species. Adult play — including gentle play fighting with restrained, turn-taking techniques — helps animals manage social tension, test relationships, and take low-stakes risks safely. Researchers such as Sergio Pellis have shown that play fighting requires behavioral inhibition and role reversal, the same self-control that underlies social competence. Retaining playfulness into adulthood is linked to self-domestication and neoteny, the carrying of juvenile traits into maturity, and play activates dopamine reward systems that make it intrinsically motivating.

How Monkeys Communicate

Monkeys communicate through a layered system of vocalizations, facial expressions, postures, and tail positions that convey threat, fear, affiliation, and identity. Reading these signals correctly is essential both for the animals themselves and for researchers decoding their social lives. The sections below break down the main channels.

Vocalizations and Communication Signals

Vocal signals let monkeys coordinate movement, defend territory, and broadcast emotional state across distance. Calls range from contact grunts that keep a foraging group together to loud, escalating screams during conflict, each shaped by the social context in which it occurs. The structure of these signals reflects the fission-fusion dynamics of many species, where subgroups split and rejoin and individuals must constantly announce their location and intentions.

Alarm Calls and Predator Warning Systems

Alarm calls are among the most sophisticated forms of monkey communication, in some species functioning almost like words. Vervet monkeys famously give acoustically distinct alarm calls for different predators — leopards, eagles, and snakes — and listeners respond with the appropriate escape behavior, running into trees, looking up, or scanning the ground. This referential signaling shows that monkeys can encode specific external information, not merely raw fear, in their vocalizations.

Facial Expressions and Lip Smacking

Affiliative facial expressions, especially the lip smack, signal friendly intent and ease social tension in macaques and many other monkeys. The lip smack — a rapid open-and-close of the lips, often during or before grooming — communicates appeasement and willingness to interact. A relaxed open-mouth play face invites play, while neutral facial expressions mark calm, non-committal states. Reading these affiliative signals correctly is a core social skill that young monkeys learn through experience.

Agonistic and Aggressive Expressions

Agonistic expressions warn of impending aggression and assert dominance. An open-mouth stare with a direct gaze is a classic threat in macaques, while a bared-teeth grimace — confusingly to human observers — usually signals fear and submission rather than hostility. Piloerection, the raising of body hair to make an animal look larger, accompanies high arousal during threats and conflicts. Crouching, freezing, and a fear grimace mark submission and attempts to avoid escalation. Tail positions add another layer: an erect or arched tail can broadcast confidence and dominance, while a lowered tail often accompanies subordinate or affiliative behavior.

Anxious Behaviors: Tense Mouth and Yawning

Anxious behaviors such as a tense, compressed mouth, repeated yawning, and self-directed scratching reveal underlying stress in monkeys. A tension yawn — distinct from a sleepy one — often appears in tense social moments or during conflict among males. Head shaking can function as both a communicative signal and a self-soothing or disciplinary gesture, while head-cocking is frequently tied to attention and learning. Recognizing these displacement behaviors lets caretakers and researchers gauge an animal's emotional state before overt distress appears.

Emotions and Affective Reactivity in Monkeys

Monkeys have genuine emotional lives, and their affective reactivity — how strongly and in what way they respond emotionally to events — can be measured systematically. Work in affective science, including research by Eliza Bliss-Moreau at the University of California Davis and the California National Primate Research Center, treats rhesus macaques (Macaca mulatta) as translatable animal models for human emotion. Standardized methods such as the human intruder paradigm and object responsiveness tests assess threat responsiveness and emotional regulation, providing windows into anxiety, fear, and reward processing that parallel human affective systems.

Emotions also shape how monkeys handle death and loss. Field reports describe monkey mothers carrying dead infants for days and group members showing subdued, attentive behavior around a dead companion — responses that look like a primate form of mourning and grief processing.

Behavioral Impacts of Maternal Separation

Maternal separation has profound, lasting effects on young monkeys, a finding central to comparative primate psychology. Infants deprived of normal maternal care show disrupted emotional development, heightened anxiety, and impaired social skills, and early isolation can leave long-term marks on stress physiology and social functioning into adulthood. Because mother-infant attachment in primates so closely resembles human attachment, these studies have profoundly shaped understanding of how early neglect affects emotional development in both monkeys and people.

Wild vs Captive Monkey Behavior

Wild and captive monkeys differ most visibly in how they spend their time, and comparing the two reveals what good welfare management requires. In the wild, much of the day goes to foraging and travel; in captivity, where food is provided, that time must be redirected or behavioral problems can emerge. Studies such as Jaman & Huffman (2013) on macaque activity budgets quantify these differences directly.

Activity Budgets and Time Allocation

Activity budgets describe how a monkey divides its day among foraging, resting, traveling, and social behaviors like allogrooming. Wild macaques typically spend large portions of the day searching for and processing food, while captive macaques, freed from that demand, often rest more and may show inflated grooming or, conversely, abnormal repetitive behaviors. Tracking these budgets gives a clear, comparable measure of how environment reshapes behavior.

Captive Environment Enrichment and Preventing Behavioral Problems

Environmental enrichment fills the behavioral gap left by easy food and limited space in captivity. Facilities such as the MRC Centre for Macaques use foraging puzzles, varied substrates, social housing, and structures for climbing to encourage natural foraging, play, and social interaction. Well-designed enrichment prevents stress-related and stereotyped behaviors, supporting both welfare and the validity of any research the animals take part in.

Studying Monkey Behavior: Methods and Tools

Researchers study monkey behavior through systematic observation, standardized coding, and quantitative analysis of social structure. Reliable findings depend on turning fleeting behaviors into consistent, comparable data, which requires both a shared vocabulary of behaviors and the right recording tools. Modern primatology combines field methodologies with video observation and statistical network analysis.

Behavioral Coding Schemes and Ethograms

An ethogram is a catalogue of defined, mutually exclusive behaviors that lets different observers code the same actions the same way. Behavioral coding schemes built on ethograms underpin reliable data collection, and software such as The Observer XT supports both live observation and frame-by-frame video analysis, including stationary observation systems that record animals continuously without a human present. These tools let researchers quantify rates and sequences of behaviors that the eye alone could never tally accurately.

Social Network Analysis in Primate Research

Social network analysis maps the web of relationships in a troop, turning grooming, proximity, and support into measurable structure. Metrics such as betweenness centrality identify individuals who connect otherwise separate parts of the network and may act as social brokers. Researchers including Brenda McCowan and Brianne Beisner have applied network analysis to captive rhesus macaque groups to predict instability and improve welfare management, showing how an individual's network position relates to its social role and the group's overall stability.

Comparative Primate and Human Behavior

Comparing monkeys and humans reveals deep continuities in social emotion, cognition, and behavior that make primates powerful models for understanding ourselves. Frans B.M. de Waal's work on fairness and food sharing showed that monkeys reject unequal rewards, reacting with what looks like a human sense of injustice when a partner receives a better payoff for the same task. Such findings, alongside parallels in attachment, grief, play, and social stress, explain why rhesus macaques and other primates serve as translatable animal models in affective science and psychology.

The extended juvenile period of primates is itself a shared signature: a long childhood gives time for muscle and brain development, social learning, and the lifelong cognitive flexibility seen in both monkeys and humans. Risk-taking in low-stakes contexts, turn-taking and behavioral inhibition during play, and the link between strong social connections and health all recur across the primate order, underscoring how much human behavior is rooted in our evolutionary kinship with monkeys and apes.

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What Do You Call a Group of Monkeys?

A group of monkeys is most commonly called a troop, though the terms barrel, tribe, and cartload are also used. Troop is the standard term in primatology because it captures the stable, organized social unit in which most monkeys live, complete with its dominance hierarchy, alliances, and grooming networks. Some species that live in fluid fission-fusion societies, such as spider monkeys, form subgroups that split and merge, but the larger social unit is still referred to as a troop.