Group (sociology)
In sociology, a group is usually defined as a collection of humans who share certain characteristics, interact with one another, accept expectations and obligations as members of the group, and share a common identity. Using this definition, society can appear as a large group.
While an aggregate comprises merely a number of individuals, a group in sociology exhibits cohesiveness to a larger degree. Characteristics that members in the group may share include interests, values,  ethnic/linguistic background, and kinship ties.

# Types of groups
Primary groups consist of small groups with intimate, kin-based relationships: families, for example. They commonly last for years. They are small and display face to face interaction.
Secondary groups, in contrast to primary groups, are large groups whose relationships are formal and institutional. Some of them may last for years but some may disband after a short lifetime. The formation of primary groups happens within secondary groups.
Individuals almost universally have a bond toward what are known as "Reference Groups". These are groups to which the individual conceptually relates him/herself, and from which he/she adopts goals and values as a part of his/her self identity.

# Common uses of the terms
The dictionary gives the word group the meaning of "lump" or "mass." A general definition is "an assemblage of objects standing near together, and forming a collective unity; a knot (of people), a cluster (of things)." The dictionary quotation by the famous British author Walter Bagehot (1826-1877) offers an important and traditional perspective on the necessity of understanding groups: "Man can only make progress in cooperative groups."1
Muzafer Sherif (1916-1982)  formulated a more technical definition with the following elements:
- A social unit consisting of a number of individuals interacting with each other with respect to:
- Common motives and goals;
- An accepted division of labor, i.e. roles,
- Established status (social rank, dominance) relationships;
- Accepted norms and values with reference to matters relevant to the group;
- Development of accepted sanctions (praise and punishment) if and when norms were respected or violated.2
This definition is long and complex, but it is also precise. It succeeds at providing the researcher with the tools required to answer three important questions:
- "How is a group formed?";
- "How does a group function?";
- "How does one describe those social  interactions that occur on the way to forming a group?"

# Significance of the definition
The attention of those who use, participate in, or study groups has been focused on functioning groups, with larger organizations, or with the decisions made in these organizations. 3 Much less attention has been paid to the more ubiquitous and universal social behaviors that do not clearly demonstrate one or more of the five necessary elements described by Sherif.
Perhaps the earliest efforts to understand these social units has been the extensive descriptions of urban street gangs in the 1920s and 1930s, continuing through the 1950s, which understood them to be largely reactions to the established authority.4 The primary goal of gang members was to defend gang territory, and to define and maintain the dominance structure within the gang. There remains in the popular media and urban law enforcement agencies an avid interest in gangs, reflected in daily headlines which emphasize the criminal aspects of gang behavior. However, these studies and the continued interest have not improved the capacity to influence gang behavior or to reduce gang related violence.
The relevant literatures on animal social behaviors, such as work on territory and dominance, have been available since the 1950s. However, they have been largely neglected by policy makers, sociologists and anthropologists. Indeed, vast literatures on organization, property, law enforcement, ownership, religion, warfare, values, conflict resolution, authority, rights, and families have grown and evolved without any reference to any analogous social behaviors in animals. This disconnect may be the result of the belief that social behavior in humankind is radically different from the social behavior in animals because of the human capacity for language use and rationality. And of course, while this is true, it is equally likely that the study of the social (group) behaviors of other animals might shed light on the evolutionary roots of social behavior in humans.
Territorial and dominance behaviors in humans are so universal and commonplace that they are simply taken for granted (though sometimes admired, as in home ownership, or deplored, as in  violence). But these social behaviors and interactions between human individuals play a special role in the study of groups: they are necessarily prior to the formation of groups. The psychological internalization of territorial and dominance experiences in conscious and unconscious memory are established through the formation of personal identity, body concept, or self concept. An adequately functioning individual identity is necessary before an individual can function in a division of labor (role), and hence, within a cohesive group. Coming to understand territorial and dominance behaviors may thus help to clarify the development, functioning, and productivity of groups.

# Development of a group
If one brings a small collection of strangers together in a restricted space and environment, provide a common goal, and maybe a few ground rules, a predictable flow of behavior will follow. Interaction between individuals is the basic requirement. At first, individuals will differentially interact in sets of twos or threes while seeking to interact with those with whom they share something in common: i.e., interests, skills, and cultural background. Relationships will develop some stability in these small sets, in that individuals may temporarily change from one set to another, but will return to the same pairs or trios rather consistently and resist change. Particular twosomes and threesomes will stake out their special spots within the overall space.
Again depending on the common goal, eventually there will be integration of twosomes and threesomes into larger sets of six or eight, and corresponding revisions of territory, dominance ranking, and further differentiation of roles. All of this seldom takes place without some conflict or disagreement: for example, fighting over the distribution of resources, the choices of means and different subgoals, the development of what are appropriate norms, rewards and punishments. Some of these conflicts will be territorial in nature: i.e., jealousy over roles, or locations, or favored relationships. But most will be involved with struggles for status, ranging from mild protests to serious verbal conflicts and even dangerous violence.
By analogy to animal behavior, these behaviors can be termed territorial behaviors and dominance behaviors. Depending on the pressure of the common goal and on the various skills of individuals, differentiations of leadership, dominance, or authority will develop. Once these relationships solidify, with their defined roles, norms, and sanctions, a productive group will have been established.5,6,7
Aggression is the mark of unsettled dominance order. Productive group cooperation requires that both dominance order and territorial arrangements (identity, self concept) be settled with respect to the common goal and with respect to the particular group. Often some individuals will withdraw from interaction or be excluded from the developing group. Depending on the number of individuals in the original collection of strangers, and the number of hangers-on that are tolerated, one or more competing groups of ten or less may be formed, and the competition for territory and dominance will then also be manifested in the intergroup transactions.

# Dispersal and transformation of groups
Two or more people in interacting situations will over time develop stable territorial relationships. As described above, these may or may not develop into groups. But stable groups can also break up in to several sets of territorial relationships. There are numerous reasons for stable groups to malfunction or to disperse, but essentially this is because of loss of compliance with one or more elements of the definition of group provided by Sherif. The two most common causes of a malfunctioning group are the addition of too many individuals, and the failure of the leader to enforce a common purpose, though malfunctions may occur due to a failure of any of the other elements (i.e., confusions status or of norms).
In a society, there is obvious need for more people to participate in cooperative endeavors than can be accommodated by a few separate groups. The military has been the best example as to how this is done in its hierarchical array of squads, platoons, companies, battalions, regiments, and divisions. Private companies, corporations, government agencies, clubs, and so on have all developed comparable (if less formal and standardized) systems when the number of members or employees exceeds the number that can be accommodated in an effective group. Not all larger social structures require the cohesion that may be found in the small group. Consider the neighborhood, country club, or the megachurch, which are basically territorial organizations who support large social purposes. Any such large organizations may need only islands of cohesive leadership.
For a functioning group to attempt to add new members in a casual way is a certain prescription for failure, loss of efficiency, or disorganization. The number of functioning members in a group can be reasonably flexible between five and ten, and a long-standing cohesive group may be able to tolerate a few hangers on. The key concept is that the value and success of a group is obtained by each member  maintaining a distinct, functioning identity in the minds of each of the members. The cognitive limit to this span of attention in individuals is often set at seven. Rapid shifting of attention can push the limit to about ten. After ten, subgroups will inevitably start to form with the attendant loss of purpose, dominance order, and individuality, with confusion of roles and rules. The standard classroom with twenty to forty pupils and one teacher is a rueful example of one supposed leader juggling a number of subgroups.
Weakening of the common purpose once a group is well established can be attributed to: adding new members; unsettled conflicts of identities (i.e., territorial problems in individuals); weakening of a settled dominance order; and weakening or failure of the leader to tend to the group. The actual loss of  a leader is frequently fatal to a group, unless there was lengthy preparation for the transition. The loss of the leader tends to dissolve all dominance relationships, as well as weakening dedication to common purpose, differentiation of roles, and maintenance of norms. The most common symptoms of a troubled group are loss of efficiency, diminished participation, or weakening of purpose, as well as an increase in verbal aggression. Often, if a strong common purpose is still present, a simple reorganization with a new leader and a few new members will be sufficient to re-establish the group, which is somewhat easier than forming an entirely new group.

# Territory and dominance

## History
There were no concepts of territory and dominance to inform the theory of Sociology in its formative stages. Great bodies of literature have developed on social relations, family, property, law enforcement, aggression, and others with only slight mention of territory or dominance. It was not until the 1950s that scientists in human psychology, human socialization, and animal social behavior began to meet together to try to integrate their perspectives. But the professional disciplines traditions, basic concepts, and research methodologies were difficult to reconcile. Psychoanalysis, with its focus on introspection, and subjective data, had become the accepted theory for many psychologists and sociologists. However, the Macy Foundation did sponsor five annual scientific conferences, and published the proceedings in five volumes entitled Group Processes between 1954 and 1958.9
Territory and Dominance are basic, primitive, and well studied social behaviors in many animals, including humans and other primates. These two well-differentiated categories of social behavior can be considered as evolutionary and developmental twins in that they are profoundly connected. Its difficult to make observations about one without commenting on the other. Yet, they are clearly differentiated. Obviously, for example, territories can be invaded, captured, or destroyed by more dominant individuals. But an individual occupying his/her own territory does have an advantage in the struggle for possession of that territory, and is able to exert increased strengths when defending his own. Noah Fox

## Recognition of territorial behavior
Territory was initially  identified as a physical space which may be staked out by individuals singly or as mating pairs. The space is subsequently defended, sometimes quite vigorously, and when left by the owner there is the strong tendency to return to it. Territories may also be claimed by various aggregates of individuals such as families, tribes, or nations. Each species has well defined patterns of when, and how territory is defined and defended. Nesting behavior in birds, hunting territory in wolves, or home ownership in humans are easy phenomena to identify. However, this initial definition was elaborated to include not only other human objects such as friends, spouses, children, but domestic animals, pets of all kinds, and physical objects such as toys, jewelry, automobiles, and golf clubs. It can also mean, in a much broader sense, anything that has been claimed for a person or group. This includes intangible things like areas of business, market share, areas of research, social scenes, contacts and how a person or groups presents itself.
Territories are strongly defended. When they are lost, sold, stolen, intruded on or captured, there may be in humans an intense sense of loss, very much akin to depression, and a sense of anger. Animals also have analogous reactions, but are naturally devoid of the expressions of emotion in language. Territory is functionally related to the survival behaviors of seeking food, shelter, sex, and reproduction, but there is no effort here to establish the survival value of territory or dominance. The universal presence of these principles in a wide variety of species would seem to argue for survival value, but there is, as yet, no scientific methodology to establish either validity or falsification of survival value. Over the long period of evolutionary time, humankind has developed a most complicated array of territorial behaviors that range from personal social relationships, to possession of land, property, and physical objects. Through the intermediation of spoken and written language, territory can be extended to abstract and symbolic objects and ideas such as religion, school, value systems, and jobs. The most obvious human territorial behaviors are the establishment of a home base, and home ownership. This extends to the ownership of many objects considered as property such as furniture, car, clothes, golf clubs, and so on. The use of the possessive pronouns (mine, yours, his, hers, ours, theirs) is a valid signal of territorial behavior recognized in self and others.

## Recognition of dominance behavior
Dominance behavior was first scientifically identified as the pecking order in chickens. But, of course, authority, differences in strength, intellect, and social rank in humans have been identified in literature and history as far back as there are records. The simplest marker for dominance is that one individual is allowed to do something that others are not allowed to do. This may be anything from deciding a tied vote to kicking a person out of the group, or worse. Aggression and fighting are markers of the absence of an established dominance order in many cases (this includes politics). However, in small groups, there can exist a system where there is NO dominance, if the group is composed of people who will not abide by one trying to gain dominance over the others. Peaceful coexistence is the marker of the existence of a stable dominance order. Human beings have creatively defined, rationalized, and institutionalized many markers of dominance and authority, ranging from uniforms, titles, insignia of rank, to tone of language, mode of address, the corner office suite, size of bank account, make of car, and so on, to the next new word, symbol, or innovative marker.

## Family territory and dominance
The family is an available, familiar, and informative social structure to use as an exemplar of the interactions of territory and dominance. This section will explore some of the ways that families exhibit territory and dominance behaviors. For the purpose of exposition, it will leave aside an unresolved variety of opinions about some of the issues discussed, i.e., revised definitions of the family.
In heterosexual nuclear families, there is usually a preexisting bond and history of interaction (courtship or dating) between a man and a woman before a family is considered formed. Other research in social psychology has provided information on the great variations in the mating selection process; however, none of these variations contradict the basic necessity of a bonding interaction between a man and a woman for the purpose of species maintenance. Most often there is an implied intention to reproduce. Indeed, sexual intercourse is a specific, required type of interaction for reproduction which undoubtedly can contribute strength of purpose to the pair's bond. Additional strength is usually contributed by the lengthy pregnancy and birth of a child. This is not to deny that pair territorial bonds may be weakened, or disrupted by other factors before, during, and after the pregnancy and delivery. The birth of a baby creates the strongest of territorial bonds -- the mother-child relationship -- and is famous for affecting (for good or bad) the husband-wife bond.
The birth of the child into a family is a clear and uncontroverted example that many of the early and stronger territorial bonds of an individual are provided without personal selection or choice by the individual. The child immediately acquires many potential territories: a mother and a father, often siblings and other relatives, an important spacial relationship to the arms of the mother, perhaps the breast of the mother, a blanket, and a cuddle toy, and a geographical home. Likewise over time the child involuntarily acquires numerous attitudes: to life, religion, social relationships, sex, aggression, learning, and so on through the complicated life from zero to six years of age. Gradually the child has some choice and preference in the selection of some objects, such as toys, and some types of food. There are, of course, examples of some young babies rejecting their nurses. Whatever the theoretical and technical flaws of Freudian psychoanalysis and psychotherapy, the thousands of hours of observation and verbalizations by subjects in these procedures provides innumerable examples of the importance of these involuntary, but long durational territorial relationships, as well as the conflicts between them.  History, biography, and fiction provides the public with multiple examples of the variations in patterns over time, culture, and even next door neighbors. But the basic patterns of family territorial bonding remain unchallenged, including homosexual families with or without formal marriage. Body (self) image, and personal identity are two of the most important dynamic territories derived over the early and late interactions and territorial bonding that occur within the family structure.
Dominance relationships within marriage and family are as familiar and as inevitable as the territorial relationships. Aristotle described the man as being the master and manager of his household to include wife, children, slaves, the ox and plough, and property.10 Roman law specified this to include the power of life and death over children. This is no longer the accepted pattern today (unless you count a fetus as a child, in which case it depends on the laws of the local area), but not even the most unobservant can deny the existence of a dominance order within every family. Many of the subtleties of territorial or dominance behavior may be taken as "just the way things are" or "the kids always fight."
Dominance patterns are universal, but not rigidly determined. Learning, culture, circumstances, as well as individual intentional efforts are continuously molding the patterns. Many women may be the overall dominant individual in the family. Some men may be subordinate in earning income, but take the leading child care role. Most modern families will have a unique pattern of shared responsibilities and dominance, but some form of dominance is inevitable, or the family would be totally dysfunctional. The rule that a stable dominance order is required for a properly functioning group is equally pertinent to the family. Most families do not function as groups, and they are not considered as such, despite the suggestion of such in the introduction to this article.
Likewise, it is perhaps the rare family that doesnt manifest some conflict within it: conflict between the mother and father and assorted relatives; sibling conflict; conflict between children and parents; conflict over money and distribution of time and other resources; and adolescents are famous for their rebelliousness. Most conflict is over who can do what to whom, or who has what kind of access to some resource or privilege. Conflict does not necessarily weaken territorial bonds, even though some conflicts last for years, or forever. Every social worker who has responsibility for children is well aware that an abused child will often vigorously resist being removed from an abusing mother, and will return to the mother if allowed. The same territorial principle helps to explain why some abused wives return again and again to an abusive husband.

## Intensity, modification, and change of a territory
Human territorial bonds are formed by the dynamic interaction of individuals with objects whether other individuals, physical objects, abstract ideas, religions, schools, or football teams. Territorial bonds vary in intensity and duration depending on the frequency of interaction, the intensity of the interaction, and the duration of the interaction. It is unlikely that a child with a reasonable normal childhood will ever forget his or her mother, but the territorial child/ mother bond can be attenuated by separation in adulthood, by infrequency of face to face interaction, failures to visit or communicate, and so on. But most people remain alert to their maternal bonding for their lifetimes. Similarly the mating and marriage bond can  undergo severe dilution by divorces, deaths, and remarriages, and lack of interaction. But it is the rare man or woman who cannot cite chapter and verse about a series of marriages, or intense relationships if motivated to do so. It is important to realize that there is nothing imperative about territory. The tendency to act in a territorial manner is deeply inborn in humans, but it is also quite modifiable by culture, learning, custom, habit, time, and most of all by replacement territories. The average individual has weak territorial feelings, and a few active memories about primary school, stronger ones about high school, even stronger about college, and perhaps still stronger about professional schools such as law, and medicine. The latter schools' territorial bonding may be somewhat weaker as the individual transfers much of the territorial bonding to the profession that he or she actually practices, and interacts with on a daily basis. The territorial feeling about the practice of law or medicine can be quite strong and the territory vigorously defended. But one does not have to be a member of a profession to have a territorial bond to ones job. Many people from mechanics to secretaries and wallpaper hangers take  pride in their jobs and their job skills. Others are simply dependent on their jobs for their livlihood, and are frightened by any threat to their wellbeing or survival whatever the cause.

## Organization
Another clearly defined function of territoriality and dominance is portrayed as the span of supervision and authority, as well as the normal flow of decision making and implementation up and down the tables of organization for all types of  organizations, military, religious, or corporate with special reference to decisions under the designations of authority and identification.11 Perhaps it is not too late to consider territory and dominance as the unifying concepts that the early sociologists searched for so avidly and unsuccessfully in their comparative studies of different societies from primitive to the most complex.12