changingminds.org

How we change what others think, feel, believe and do

| Menu | Quick | Books | Share | Search | Settings |

Dunbar's Number

 

Explanations > Groups > Dunbar's Number

Description | Discussion | See also

 

Description

Dunbar's number is 150. This is approximate number of people we are programmed by evolution to know with some reasonable degree of familiarity.

Discussion

In the very long and relatively stable history of human evolution, people lived in loose communities in which they knew everyone. The Social Brain Hypothesis (originally the Machiavellian Intelligence Hypothesis) suggests that the human brain is larger because it allows us to live in socially complex societies. This is noted particularly in the size of the frontal lobe of the neocortex where social juggling takes place.

This is one reason why small communities and companies thrive well up to around Dunbar's number. After that, they go through a barrier beyond which not everyone knows everyone that well and the social dynamics change.

Dunbar is an anthropologist who studied the size of groups (as well as the development of language and brain size). By correlating group size and brain size across a range of 36 types of primate, he interpolated the human 'mean group size' as 147.8. Given natural variation, 150 is a reasonable round number.

Dunbar also concluded that, in order for a group of this size to remain together, 42% of its members' time should be spent in social grooming, building trust and social capital. A key point about this is that grooming time steadily increases with group size, and that there is a natural crossover point where a larger group would result in conflict in time spent between grooming and other sustaining activities.

See also

Dunbar, R. I. M. (1995). Neocortex size and group size in primates: A test of the hypothesis. Journal of Human Evolution, 28, 287-296.

Whiten, A., and R. W. Byrne. (1988). The Machiavellian intellect hypotheses. In R. W. Byrne and A. Whiten, Eds., Machiavellian Intelligence. Oxford: Oxford University Press, 1-9.

 

Site Menu

| Home | Top | Quick Links | Settings |

Main sections: | Disciplines | Techniques | Principles | Explanations | Theories |

Other sections: | Blog! | Quotes | Guest articles | Analysis | Books | Help |

More pages: | Contact | Caveat | About | Students | Webmasters | Awards | Guestbook | Feedback | Sitemap | Changes |

Settings: | Computer layout | Mobile layout | Small font | Medium font | Large font | Translate |

 

You can buy books here

More Kindle books:

And the big
paperback book


Look inside

 

Please help and share:

 

Quick links

Disciplines

* Argument
* Brand management
* Change Management
* Coaching
* Communication
* Counseling
* Game Design
* Human Resources
* Job-finding
* Leadership
* Marketing
* Politics
* Propaganda
* Rhetoric
* Negotiation
* Psychoanalysis
* Sales
* Sociology
* Storytelling
* Teaching
* Warfare
* Workplace design

Techniques

* Assertiveness
* Body language
* Change techniques
* Closing techniques
* Conversation
* Confidence tricks
* Conversion
* Creative techniques
* General techniques
* Happiness
* Hypnotism
* Interrogation
* Language
* Listening
* Negotiation tactics
* Objection handling
* Propaganda
* Problem-solving
* Public speaking
* Questioning
* Using repetition
* Resisting persuasion
* Self-development
* Sequential requests
* Storytelling
* Stress Management
* Tipping
* Using humor
* Willpower

Principles

* Principles

Explanations

* Behaviors
* Beliefs
* Brain stuff
* Conditioning
* Coping Mechanisms
* Critical Theory
* Culture
* Decisions
* Emotions
* Evolution
* Gender
* Games
* Groups
* Habit
* Identity
* Learning
* Meaning
* Memory
* Motivation
* Models
* Needs
* Personality
* Power
* Preferences
* Research
* Relationships
* SIFT Model
* Social Research
* Stress
* Trust
* Values

Theories

* Alphabetic list
* Theory types

And

About
Guest Articles
Blog!
Books
Changes
Contact
Guestbook
Quotes
Students
Webmasters

 

| Home | Top | Menu | Quick Links |

© Changing Works 2002-
Massive Content — Maximum Speed

Site Menu

| Home | Top | Quick Links | Settings |

Main sections: | Disciplines | Techniques | Principles | Explanations | Theories |

Other sections: | Blog! | Quotes | Guest articles | Analysis | Books | Help |

More pages: | Contact | Caveat | About | Students | Webmasters | Awards | Guestbook | Feedback | Sitemap | Changes |

Settings: | Computer layout | Mobile layout | Small font | Medium font | Large font | Translate |

 

 

Please help and share:

 

Quick links

Disciplines

* Argument
* Brand management
* Change Management
* Coaching
* Communication
* Counseling
* Game Design
* Human Resources
* Job-finding
* Leadership
* Marketing
* Politics
* Propaganda
* Rhetoric
* Negotiation
* Psychoanalysis
* Sales
* Sociology
* Storytelling
* Teaching
* Warfare
* Workplace design

Techniques

* Assertiveness
* Body language
* Change techniques
* Closing techniques
* Conversation
* Confidence tricks
* Conversion
* Creative techniques
* General techniques
* Happiness
* Hypnotism
* Interrogation
* Language
* Listening
* Negotiation tactics
* Objection handling
* Propaganda
* Problem-solving
* Public speaking
* Questioning
* Using repetition
* Resisting persuasion
* Self-development
* Sequential requests
* Storytelling
* Stress Management
* Tipping
* Using humor
* Willpower

Principles

+ Principles

Explanations

* Behaviors
* Beliefs
* Brain stuff
* Conditioning
* Coping Mechanisms
* Critical Theory
* Culture
* Decisions
* Emotions
* Evolution
* Gender
* Games
* Groups
* Habit
* Identity
* Learning
* Meaning
* Memory
* Motivation
* Models
* Needs
* Personality
* Power
* Preferences
* Research
* Relationships
* SIFT Model
* Social Research
* Stress
* Trust
* Values

Theories

* Alphabetic list
* Theory types

And

About
Guest Articles
Blog!
Books
Changes
Contact
Guestbook
Quotes
Students
Webmasters

 

| Home | Top | Menu | Quick Links |

© Changing Works 2002-
Massive Content — Maximum Speed