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Related Experiment Video

Updated: Mar 24, 2026

Manipulation of Color Patterns in Jumping Spiders for Use in Behavioral Experiments

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Published on: May 21, 2019

Negative-assortative mating for color in wolves.

Philip W Hedrick¹, Douglas W Smith², Daniel R Stahler²

¹School of Life Sciences, Arizona State University, Tempe, Arizona, 85287. philip.hedrick@asu.edu.

Evolution; International Journal of Organic Evolution

|March 19, 2016

Summary

This summary is machine-generated.

Yellowstone wolves exhibit strong negative-assortative mating, where gray and black wolves preferentially mate with the opposite color. This mating pattern is crucial for maintaining the wolf population's color diversity.

Keywords:

Beta-defensin MHC disassortative mating fixation index heterozygote advantage polymorphism selection

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Area of Science:

Ecology
Evolutionary Biology
Behavioral Ecology

Background:

Pelage color polymorphism in Yellowstone wolves is a well-known phenomenon.
Understanding the mating preferences and their genetic consequences is key to explaining this polymorphism.

Purpose of the Study:

To investigate the mating patterns of gray and black wolves in Yellowstone National Park.
To determine if negative-assortative mating plays a role in maintaining coat color diversity.

Main Methods:

Analysis of 261 documented wolf matings between 1995 and 2015.
Statistical correlation analysis of mate color pairings.
Population genetic modeling to estimate mating frequencies and allele frequencies.

Main Results:

A significant negative correlation (-0.266) was found between the pelage color of mated wolves.
63.6% of observed matings were between gray and black wolves, indicating strong negative-assortative mating.
Population genetic models supported negative-assortative mating as a primary driver for stable color polymorphism.

Conclusions:

Negative-assortative mating is strongly evident in Yellowstone wolves, favoring gray-black pairings.
This mating strategy is a significant factor in the long-term maintenance of coat color variation in this population.
This study provides the first evidence of significant negative-assortative mating in mammals for coat color.