Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Robbers Cave

Robbers Cave

During the 1950s, the landmark Robbers Cave experiment demonstrated that when groups must compete with one another, intergroup conflict, hostility, and even violence may result. At the Oklahoman summer camp, two troops of boys—termed the Rattlers and the Eagles—took part in a week-long tournament. During this time, their negativity culminated in derogatory name-calling, fistfights, and even vandalism and destruction of property. However, this work also revealed that such tension...

Social Facilitation

Social Facilitation

Not all intergroup interactions lead to negative outcomes. Sometimes, being in a group situation can improve performance. Social facilitation occurs when an individual performs better when an audience is watching than when the individual performs the behavior alone. This typically occurs when people are performing a task for which they are skilled.

Group Polarization

Group Polarization

Group polarization is the strengthening of an original group attitude following the discussion of views within a group (Teger & Pruitt, 1967). That is, if a group initially favors a viewpoint, after discussion the group consensus is likely a stronger endorsement of the viewpoint. Conversely, if the group was initially opposed to a viewpoint, group discussion would likely lead to stronger opposition.

Agonism and Antagonism: Quantification

Agonism and Antagonism: Quantification

When drugs are administered, they can elicit either an agonist or antagonist effect on the body. Agonism occurs when a drug activates a specific receptor, triggering a biological response. On the other hand, antagonism happens when a drug binds to the same receptors but blocks their activation, thereby preventing a biological response.
To quantify these effects, researchers use a dose-response curve, which provides valuable information about the potency and efficacy of a drug. Potency refers to...

Combined Effects of Drugs: Synergism

Combined Effects of Drugs: Synergism

Synergism is a useful mechanism where combining two or more drugs is more effective than each constituent used alone. Such combinations are also called supra-additive interactions. The drugs collectively enhance the final therapeutic effect by acting on different targets. Another advantage is that the low dose of each constituent drug is sufficient to achieve the desired effect. This helps reduce the duration of therapy and lower the adverse effects of these drugs.
Such synergistic combinations...

Social Loafing

Another way in which a group presence can affect performance is social loafing—the exertion of less effort by a person working together with a group. Social loafing occurs when our individual performance cannot be evaluated separately from the group. Thus, group performance declines on easy tasks (Karau & Williams, 1993). Essentially individual group members loaf and let other group members pick up the slack. Because each individual’s efforts cannot be evaluated,...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Narcissism as an Adaptive Trait for Successful Migration.

Evolutionary psychology : an international journal of evolutionary approaches to psychology and behavior·2026

Same author

Philip G. Zimbardo (1933-2024).

The American psychologist·2025

Same author

Philip G. Zimbardo (1933-2024).

The American psychologist·2025

Same author

Dispositional Fear and Political Attitudes.

Human nature (Hawthorne, N.Y.)·2020

Same author

Ethics in field experimentation: A call to establish new standards to protect the public from unwanted manipulation and real harms.

Proceedings of the National Academy of Sciences of the United States of America·2020

Same author

Making America less.

Nature human behaviour·2019

Search research articles

Related Experiment Video

Updated: Jul 5, 2025

A Task for Assessing the Impact of a Partner on the Speed and Accuracy of Motor Performance in Rats

A Task for Assessing the Impact of a Partner on the Speed and Accuracy of Motor Performance in Rats

Published on: October 17, 2019

Enhanced cooperation increases the capacity for conflict.

Rose McDermott¹

¹Department of Political Science, Brown University, Providence, RI, USA Rose_McDermott@Brown.eduhttps://watson.brown.edu/people/faculty/mcdermott.

The Behavioral and Brain Sciences

|January 15, 2024

Summary

This summary is machine-generated.

Enhanced cooperation in humans enables large-scale warfare and male coalitionary behavior. The study questions if female cooperation evolved similarly, noting unstable leadership in coalitions can spark conflict.

More Related Videos

Diagonal Method to Measure Synergy Among Any Number of Drugs

Diagonal Method to Measure Synergy Among Any Number of Drugs

Published on: June 21, 2018

High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method

High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method

Published on: May 21, 2018

Related Experiment Videos

Last Updated: Jul 5, 2025

A Task for Assessing the Impact of a Partner on the Speed and Accuracy of Motor Performance in Rats

A Task for Assessing the Impact of a Partner on the Speed and Accuracy of Motor Performance in Rats

Published on: October 17, 2019

Diagonal Method to Measure Synergy Among Any Number of Drugs

Diagonal Method to Measure Synergy Among Any Number of Drugs

Published on: June 21, 2018

High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method

High-throughput Identification of Synergistic Drug Combinations by the Overlap2 Method

Published on: May 21, 2018

Area of Science:

Evolutionary anthropology
Behavioral ecology
Social dynamics

Background:

Human cooperation facilitates large-scale warfare capabilities.
Male coalitionary behavior is a key aspect of human social evolution.
The evolutionary trajectory of female cooperation remains less understood.

Purpose of the Study:

To investigate the evolutionary parallels and divergences of cooperation in human males and females.
To explore the role of cooperation in the development of coalitionary behavior and leadership structures.
To understand the inherent instability within hierarchical leadership and its link to conflict.

Main Methods:

Comparative analysis of cooperative strategies across sexes.
Theoretical modeling of coalition formation and stability.
Review of anthropological and primatological data on social behavior.

Main Results:

Cooperation significantly enhances capacities for group conflict and warfare.
Male coalitionary behavior is foundational, but female cooperation's evolutionary drivers require further study.
Hierarchical leadership within coalitions is prone to instability, increasing conflict potential.

Conclusions:

Cooperation is a double-edged sword, enabling both complex social structures and intense conflict.
Understanding sex-specific evolutionary pathways of cooperation is crucial for comprehending human sociality.
The inherent instability of leadership in cooperative groups is a significant factor in conflict emergence.