24 Primate behaviour

Mr. Vineet Kumar Verma and Prof. A.K. Kapoor

 

Contents:

  • Introduction
  • Definition of primate
  • Anthropological concerns in study of Primatology
  • Primate Studies
  • Disciplinary Identity of Primatology
  • Behavioural ecology
  • Behavioural genetics
  • Evolution of Behaviour
  • Chief characteristics of primate
  • Why Be Social?
  • Social group
  • Dominance
  • Communication
  • Common Topography
  • Sense of Unity
  • Food dependency on their specific environment
  • Aggressive Interactions
  • Chimpanzee facial expressions
  • Affiliation and Altruism
  • Grooming
  • Reproduction and Reproductive Behaviours
  • Female and Male Reproductive Strategies
  • Sexual selection
  • Primate Cultural Behaviour
  • Language
  • Body Size
  • Diet
  • Predation
  • Relationships with Other, Non predatory Species
  • Dispersal
  • Distribution and Types of Sleeping Sites
  • Activity Patterns
  • Summary

 

Learning Objectives:

  • To determine the Disciplinary identity of primatology
  • To able to define the concept of Primate that have been made in Anthropology
  • To determine the distinct general and specific characteristics of Primate
  • To be able to define and distinguish between Primate and non human primate
  • To able to define an exclusive social behaviour of primates.
  • An attempt to classify the course of primate evolutionary development.
  • To able to define the process of examining source integrated approach to the study of Primate group
  • Anthropological concerns in primate population and their distribution

 

Introduction

 

As the world becomes more complex it is increasing important to understand primate behaviour and their diversity. An anthropological perspective on primate includes a consideration of all aspects of social habits of the population. It not only includes the ways in which species live but also how it is affected on the local surrounding arenas. There are so many things new about the study of primate by the scientific approach on the origins, the behaviour and the physical, development of primates.

 

One of the major goals of primatology is to determine how behaviours influence reproductive fitness and how ecological factors have shaped the evolution of these behaviours. While the actual mechanics of behavioural evolution aren’t yet fully understood, new technologies are beginning to help scientists answer many questions. For example, genetic analysis has recently been used to establish paternity in a few primate groups and this has helped support hypotheses about some behaviour; but in general, an evolutionary approach to the study of behaviour doesn’t provide definitive answers to many research questions. Rather, it provides a framework within which primatologists analyze data to generate and test hypotheses concerning behavioural patterns.

 

The fundamental principle of behavioural evolution is that aspects of behaviour (including social behaviour) are influenced by genetic factors. And because some behavioural elements are therefore inherited, natural selection can act on them in the same way it acts on physical and anatomical characteristics.

 

Because primates are among the most social of animals, social behaviour is one of the major topics in primate research. This is a broad subject that includes all aspects of behaviour that occur in social groupings, even some you may not think of as social behaviours, like feeding or mating. To understand the function of one behavioural element, it’s necessary to determine how it’s influenced by numerous interrelated factors.

 

Definition of primate

 

On the basis of certain universal characteristics contained in various definitions, proposed definition of primate claiming; stated that primitive man, in his own development, had already taken that vital step of shifting from natural arithmetic to the use of signs; found the same shift in the development of memory and thinking, therefore assume that this is the general direction taken by the historical development of human behaviour.

 

Primates are characterized by large brains relative to other mammals, as well as an increased reliance on stereoscopic vision at the expense of smell, the dominant sensory system in most mammals. These features are more developed in monkeys and apes and noticeably less so in lorises and lemurs.

 

Relation to the earliest time history or stages, development and primitive is related to the word prime, and the root of both words is primus, which is Latin for “first.” Since the phrase “primitive man” refers to the world’s first people, the word primate has something to do with the similarity between early humans and monkeys, but it doesn’t. Monkey, apes, and humans are called primates because they’re seen as standing on the first, or highest, rung of the animal-kingdom ladder.

 

Anthropological concerns in study of Primatology

 

Primate studies often use an ecological approach to explain variation in primate behaviour between different species and within a single species. The focus is on habitat, specifically contrasting terrestrial and arboreal species. At the same time, ethological studies address animal behaviours in a scientific fashion. Behaviour is anything organisms do that involves action in response to internal or external stimuli. The response can be that of an individual, group, or species to its environment. Such responses may or may not be deliberate, and they aren’t necessarily the results of conscious decision making.

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Disciplinary Identity of Primatology

 

Primatology is a developed sub-branch of Anthropology; refers to the application of anthropological perspectives to the multidisciplinary branch of primate studies. In addition, they are interested in biological origins, evolution and variation. They give primary attention to investigating questions having to do with evolutionary theory, our place in nature, adaptation and biological variation. To understand these processes, biological anthropologists study other primates (primatology), the fossil record (paleoanthropologist), prehistoric people (bio archaeology), and the biology e.g., health, cognition, hormones, growth and Development) and genetics of living populations.

 

Anthropologists are highly specialized in research interests, yet remain generalists in observations of the primate condition and advocate for anthropology that is committed to bringing knowledge to broad audiences.

  • Studying first hand and reporting about the ways of living of primate behaviour.
  • Trying to understand how various dimensions of communication, and so forth—relate to one another in generally.
  • Understanding the causes and consequences of behavioural change
  • Finally, enhancing understanding and appreciation of their differences and diversity
  • Through analyzing fossils, comparing DNA sequences and other methods, the outlines of human evolution are becoming clear.

Behavioural ecology

 

Primate studies by the mid-1980 had shifted toward behavioural ecology and so the science of behavioural ecology. Behavioural ecology studies the relationship between behaviours, natural environment, and biological traits of the species. The ecological perspective pertains to relationships between organisms and all aspects of their environment (temperature, predators, vegetation, availability of food and water, types of food, disease organisms, parasites, etc.). Behaviours and behavioural patterns have been selected because they increase reproductive fitness in individuals in specific ecological contexts. These studies are based on the assumption that animals, plants, and microorganisms evolved together.

 

Scientists study behaviour in free-ranging primates from an ecological and evolutionary perspective, meaning that they focus on the relationship between behaviours, the natural environment, and various physiological traits of the species in question. This approach is called behavioural ecology, and it’s based on the underlying assumption that all of the biological components of ecological systems (animals, plants, and even microorganisms) evolved together. Therefore, behaviours are adaptations to environmental circumstances that existed in the past as much as in the present.

Source: http://www.sfu.museum

 

Briefly, the cornerstone of this perspective is that behaviours have evolved through the operation of natural selection. But in many vertebrates, especially birds and mammals, the proportion of behaviour that’s due to learning is substantially increased, and the proportion under genetic control is reduced. This is especially true of primates; and in humans, who are so much a product of culture, most behaviour is learned.

 

Behavioural genetics

 

Behavioural genetics, the study of how genes influence behaviour, is a fairly new field. This lands right in the middle of the nature-nurture question in that complex relationships exist between genetic and environments components. Behaviour constitutes a phenotype and so individuals whose behavioural phenotypes increase reproductive fitness pass on their genes at a faster rate. Genes do not code for specific behaviours, however (i.e. aggression, cooperation, etc. Species vary in their limits and potentials for learning and behavioural flexibility, set by genetic factors. Natural selection acts on genetic factors shaped by ecological setting of past and present.

 

Evolution of Behaviour

 

A major goal of primatology is to determine how behaviours influence reproductive fitness and how ecological factors have shaped the evolution of these behaviours. Because primates are among the most social of animals, social behaviour is a major topic in primate research. Technically, what we are talking about is the study of primate social structure

 

A social structure is defined as the composition, size, and sex ratio of a group of animals. Social structures guide individual interactions and social relationships. The subject is broad, including all aspects of behaviour that occur in social settings

 

Chief characteristics of primate

 

The Primates have characteristics of their own. They differ from the species population both in character and passing through an accelerated phase of transformation and equilibrium Anthropological approach to human and nonhuman primate behaviour and cognition predicts biological specializations for social life. Focusing on nonhuman primates, its describe how the primate brain might implement social functions by co-opting and extending pre existing mechanisms that previously supported non social functions.

 

These specializations for social behaviour reflect a rich evolutionary heritage of adaptation to group life. Like humans, many other primates also live in large groups characterized by patterns of primate behaviour are the following:

  • grooming,
  • imitative
  • cooperative foraging,
  • differentiated affiliative relationships,
  • ritualized courtship
  • mating behavior, and
  • competitive interactions structured by social dominance.
  • Not  surprisingly,  the  ability  to  deftly  navigate  the  social  environment  has  observable consequences for reproductive success in some primates.

 

Anthropological approach to the study of primate social behaviour is powerful in the extent to which it is encompassing and holistic. By presenting the evolution of social behaviour through a lens of social functions, and have provided evolutionarily parsimonious lines of reasoning and evidence, along with tractable avenues for future changes.

 

Why Be Social?

 

The costs of competition are offset by the benefits of predator defence provided by associating with others. Groups made up of several adult males and females are advantageous in areas where predation pressure is high, particularly in mixed woodlands and on open savannas. Leopards are the most significant predator of terrestrial primates. Where members of prey species occur in larger groups, the chances of early predator detection and avoidance are increased simply because there are more pairs of eyes looking about. There really is safety in numbers.

 

Primate Social Behaviour

 

Because primates solve their major adaptive problems in a social context, should expect several behaviours that reinforce group integrity, all these behaviours have evolved as adaptive responses during millions of years of primate evolution.

 

Social group

 

There are advantages: facilitation of reproduction; predator avoidance and defence; help with foraging for food; help with learning; and a division of labor: males and females do slightly different things. Savannah baboons are an excellent example of these advantages. Social evolution (sociality) has occurred among several forms of life, but by no means all Social life, to have evolved at all, must have enhanced the chances of individual organisms to survive and reproduce.

 

Dominance

 

Many primate societies are organized into dominance hierarchies, which impose certain degree of order by establishing parameters of individual behaviour. Although aggression is frequently a means of increasing one’s status, dominance usually serves to reduce the amount of actual physical violence. Not only are lower-ranking animals unlikely to attack or even threatening a higher-ranking one, but dominant animals are usually able to exert control simply by making a threatening gesture.

 

Communication

 

Communication is universal among animals and includes scents and unintentional, autonomic responses and behaviours that convey meaning. Such attributes as body posture convey information about an animal’s emotional state. Moreover, autonomic responses to threatening or novel stimuli, such as raised body hair (most species) or enhanced body odour (gorillas), indicate excitement. All nonhuman animals use various body postures, vocalizations, and facial expressions to transmit information. But the array of communicative devices is much richer among nonhuman primates, even though they don’t use language the way humans do. Communication is important, because it makes social living possible. Through submissive gestures, aggression is reduced and physical violence is less likely. Likewise, friendly intentions and relationships are reinforced through physical contact and grooming. Indeed, humans can see ourselves in other primate species most clearly in their use of nonverbal communication, particularly because some of their gestures and facial expressions carry the same meaning as ours do.

 

Common Topography

 

They live within a definite topography and it is a common place for occupying that region. In the absence of a common but definite living place,

 

Sense of Unity

 

Sense of unity is an invariable necessity for a true life. The very existence of depends upon each other show sense of unity.

 

Food dependency on their specific environment

 

In many cases, primate more adjusted to their physical environment sources of subsistence and livelihood; starting from the pure and simple parasitic habit for the food who depend mostly on nature for the sources of subsistence.

 

Aggressive Interactions

 

Within primate societies, there is interplay between aggressive behaviours, which can lead to group disruption, and affiliative behaviours, which promote group cohesion. Conflict within a group frequently develops out of competition for resources, including mating partners or food. Instead of actual attacks or fighting, most aggression occurs in the form of various signals and displays, frequently within the context of a dominance hierarchy. Therefore, the majority of tense situations are resolved through various submissive and appeasement behaviours. However, not all conflicts are resolved peacefully. Competition between males for mates can result in injury and even death. Females also compete with each other, frequently for resources, and especially low-ranking females may starve when food supplies are short .

 

Chimpanzee facial expressions

Affiliation and Altruism

 

As you’ve just seen, even though it can be destructive, a certain amount of aggression helps maintain order within groups and protect resources. Fortunately, to minimize actual violence and to defuse potentially dangerous situations, there are much behaviour that reinforce bonds between individuals and enhance group stability. Common affiliative behaviours include reconciliation, consolation, and simple amicable interactions between friends and relatives. These involve various forms of physical contact; in fact, physical contact is one of the most important factors in primate development, and it’s crucial in promoting peaceful relationships in many primate social groups.

 

Grooming

 

Grooming is one of the most important affiliative behaviours in many primate species, although grooming occurs in other animal species, social grooming is mostly a primate activity, and it plays an important role in day-to-day life. Because grooming involves using the fingers to pick through the fur of another individual to remove insects, dirt, and other materials, it serves hygienic functions. But it’s also an immensely pleasurable activity that members of some species (especially chimpanzees) engage in for long periods of time.

 

Altruism, behaviour that benefits another while involving some risk or sacrifice to the performer, is common in many primate species, and altruistic acts sometimes contain elements of what might be interpreted as compassion and cooperation.

 

Reproduction and Reproductive Behaviours

 

In most primate species, sexual behaviour is tied to the female’s reproductive cycle, with females being receptive to males only when they’re in oestrus. Oestrus is characterized by behavioural changes that indicate that a female is receptive. In Old World monkeys and apes that live in multi male-multi female groups, oestrus is also accompanied by swelling and changes in colour of the skin around the genital area. These changes serve as visual cues of a female’s readiness to mate.

 

Female and Male Reproductive Strategies

 

Primates are among that individuals produce only a few young, in whom they invest a tremendous amount of parental care. Primates are completely helpless at birth, and because they develop slowly, they’re exposed to expanded learning opportunities within a social environment. This trend has been elaborated most dramatically in great apes and humans, especially the latter. So human and primate relatives (and presumably in our more recent ancestors) is a strategy in which at least one parent, usually the mother, makes an extraordinary investment to produce a few “high-quality,” slowly maturing offspring.

 

Sexual selection

 

Sexual selection in primates is most common in species in which mating is polygynous and there is considerable male competition for females. In these species, sexual selection produces dimorphism with regard to a number of traits, most noticeably body size. Conversely, in species that live in pairs (such as gibbons) or where male competition is reduced, sexual dimorphism is either reduced or nonexistent. For this reason, the presence or absence of sexual dimorphism in a species can be a reasonably good indicator of mating structure.

 

Primate Cultural Behaviour

 

One important trait that makes primates, and especially chimpanzees, attractive as models for behaviour called cultural behaviour. Although many cultural anthropologists and others prefer to use the term culture to refer specifically to human activities, most biological anthropologists consider it appropriate to use the term in reference to nonhuman primates too.

 

Language

 

One of the most significant events in human evolution was the development of language; already described several behaviours and autonomic responses that convey information in primates. But although we emphasized the importance of communication to nonhuman primate social life, we also said that nonhuman primates don’t use language the way humans do. The view traditionally held by most linguists and behavioural psychologists has been that nonhuman communication consists of mostly involuntary vocalizations and actions that convey information solely about the emotional state of the animal (anger, fear, and so on).

 

Factors influence Social Structure

 

Body Size

 

As a general rule, larger animals require fewer calories per unit of weight than smaller animals because they have a smaller ratio of surface area to mass than smaller animals. Since body heat is lost at the surface, larger animals can retain heat more efficiently, and so they require less energy overall.

 

Diet

 

Since the nutritional requirements of animals are related to the previous two factors, all three have evolved together. Therefore, when primatologists study the relationships between diet and behaviour, they consider the benefits in terms of energy (calories) derived from various food items against the costs (energy expended) of obtaining and digesting them. While small-bodied primates focus on high-energy foods, larger ones don’t necessarily need to. For instance, gorillas eat leaves, pith from bamboo stems, and other types of vegetation, and they don’t need to use much energy searching for food, since they are frequently surrounded by it.

 

Predation

 

Primates, depending on their size, are vulnerable to many types of predators, including snakes, birds of prey, leopards, wild dogs, lions, and even other primates. Their responses to predation depend on their body size, social structure, and the type of predator. Typically, where predation pressure is high and body size is small, large communities are advantageous.

 

Relationships with Other, Non predatory Species

 

Many primate species associate with other primate and non primate species for various reasons; including predator avoidance. When they share habitats with other species, they exploit somewhat different resources.

 

Dispersal

 

Dispersal is another factor that influences social structure and relationships within groups. As is true of most mammals, members of one sex leave the group in which they were born their natal group about the time they reach puberty. Male dispersal is the most common pattern in primates (ring-tailed lemurs and macaques, to name a few. Female dispersal is seen in some species, baboons, chimpanzees, and mountain gorillas. This commonality has led primatologists to conclude that the most valid explanations for dispersal are probably related to two major factors: reduced competition for mates particularly between males and, perhaps even more important, the decreased likelihood of close inbreeding.

 

Distribution and Types of Sleeping Sites

 

Gorillas are the only nonhuman primates that sleep on the ground. Primate sleeping sites can be in trees or on cliff faces and their spacing can be related to social structure and predator avoidance.

 

Activity Patterns

 

Most primates are diurnal, but several small-bodied prosimians and one new world monkey owl monkey are nocturnal. Nocturnal primates tend to forage for food alone or in groups of two or three, and many hide to avoid predators.

 

Summary

 

Primatology as a field within the broad discipline of social sciences and humanities dealing with the relationship between the primate and their behaviour; its subject of the evolution of behaviour is extremely complex because it requires research into the interactions of dozens, if not hundreds, of ecological and physiological variables; treats as separate various substantive spheres of human development and also about different places of primitive world(physical, perceptual, cognitive, linguistic, personality, and social), as it does various temporal phases of development (prenatal life,infancy, childhood, adolescence, adulthood, and old age). However, human beings are coherent wholes, and behavioural development is unified, so that development in any one arena of life at any one time is ineluctably interrelated with development in other arenas at the same and at other times in patterns of mutual influence.

 

References

  • Ankel-Simons,F (2000): Primate Anatomy: an Introduction. Academic Press, London.
  • Benefit,BR; M.L. McCrossin,ML (1997): Earliest known Old World Monkey skull. Nature 388: 368—371.
  • Conroy,GC (1990): Primate Evolution. Norton, London.
  • Dean,C (1992): Jaws and teeth. In: The Cambridge Encyclopedia of Human Evolution (Jones,S; Martin,R; Pilbeam,D, eds.) Cambridge University Press, Cambridge, 56—59.
  • Fleagle,JG (1999): Primate Adaptation and Evolution. Academic Press, London.
  • Gingerich,PD (1986): Plesiadapis and the delineation of the order Primates. In: Major topics in primate and human evolution. (Wood,B; Martin,L; Andrews,P, eds.) Cambridge, Cambridge University Press, 32—46.
  • Jurmain,R; Nelson,H (1994): Introduction to physical anthropology. West Publishing Company, St. Paul, Minneapolis.
  • Kelley,J (1992): Evolution of Apes. In: The Cambridge Encyclopedia of Human Evolution (Jones,S; Martin,R; Pilbeam,D, eds.) Cambridge University Press, Cambridge, 223—230.
  • Lambert,D (1985): The Cambridge Guide to Prehistoric Life. Cambridge University Press, Cambridge.
  • Lambert,D (1987): The Cambridge Guide to Prehistoric Man. Cambridge University Press, Cambridge. Missing Links 20 Primate Evolution
  • Martin,RD (1986): Primates: a definition. In: Major topics in primate and human evolution. (Wood,B; Martin,L; Andrews,P, eds.) Cambridge, Cambridge University Press, 1—31.
  • Martin,R; Soligol,C; Tavare,S; Will,O; Marshall,C (2000): New Light on the Dates of Primate Origins and Divergence. Primate Eye 72.
  • McKenna,M (1980): Early history and biogeography of South America’s extinct land mammals. Plenum, New York.
  • Rowe,N (1996): The Pictorial Guide to Living Primates. Pogonias Press, New York.
  • Strickberger,MW (1990): Evolution. Jones and Bartlett, Boston.
  • Szalay,FS (1977): Phylogenetic relationships and a classification of the eutherian Mammalia.
  • In: Major Patterns of Vertebrate Evolution. (Hecht,MK; Goody,PC; Hecht,BM, eds.) Plenum Press, New York, 315—374.
  • Szalay,F; Delson,E (1979): Evolutionary History of the Primates. Academic Press, New York.
  • Valen,LV; Sloan,R (1965): The Earliest Primates. Science 150: 743—745