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Related Experiment Video

Updated: Mar 21, 2026

Methods of Pairing and Pair Maintenance of New Zealand White Rabbits Oryctolagus Cuniculus Via Behavioral Ethogram, Monitoring, and Interventions

Methods of Pairing and Pair Maintenance of New Zealand White Rabbits Oryctolagus Cuniculus Via Behavioral Ethogram, Monitoring, and Interventions

Published on: March 16, 2018

Do gray wolves (Canis lupus) support pack mates during aggressive inter-pack interactions?

Kira A Cassidy¹, Richard T McIntyre²

¹Yellowstone Wolf Project, Yellowstone Center for Resources, PO Box 168, Yellowstone National Park, WY, 82190, USA. kira_cassidy@nps.gov.

Animal Cognition

|May 20, 2016

Summary

Gray wolves exhibit altruistic behavior, intervening when pack mates are attacked by rivals. This costly defense, observed in Yellowstone, sheds light on the evolution of cooperation and sociality in mammals.

Keywords:

Aggression Altruism Canis lupus Cooperation Empathy Fighting Kin selection Reciprocal altruism Support

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Published on: January 24, 2025

Area of Science:

Ethology
Behavioral Ecology
Evolutionary Biology

Background:

Social coordination is crucial for group-living mammals, enhancing success in hunting, foraging, and defense.
Cooperation and costly altruistic behaviors are key factors in the evolution of sociality.
Gray wolf social structure relies on familiarity, communication, and cooperation for survival and resource protection.

Purpose of the Study:

To investigate instances of altruistic intervention during inter-pack conflicts in gray wolves.
To analyze the frequency and context of pack mates defending each other from rival attacks.
To discuss these observations in the framework of cooperation, sociality, and altruism evolution.

Main Methods:

Observation of 121 territorial aggressive inter-pack interactions in Yellowstone National Park over 16 years (1995-2011).
Detailed examination of interactions where a wolf intervened during an attack on a pack mate by a rival group.
Recording the frequency of such interventions and the relatedness of involved individuals.

Main Results:

Intervention by a pack mate during an attack by a rival group was recorded in six instances (17.6% of attacks).
These altruistic interventions often occurred between closely related individuals within the pack.
The behavior highlights costly defense, where an individual risks harm to protect a group member.

Conclusions:

The observed wolf behavior provides empirical evidence for altruism in a wild social mammal.
Inter-pack defense in wolves supports theories on the evolution of cooperation and social bonds.
Understanding these costly behaviors is essential for comprehending the adaptive significance of sociality.