Variation in mate preference across a house mouse hybrid zone

Area of Science:

• Evolutionary biology
• Behavioral ecology
• Genetics

Background:

• Reproductive character displacement occurs at secondary contact zones between European house mouse subspecies (Mus musculus musculus and Mus musculus domesticus).
• Selection against hybridization drives divergence in reproductive traits, including mate preference.

Purpose of the Study:

• To investigate mate preference patterns in naturally occurring hybrids of European house mouse subspecies.
• To compare the cline of behavioral mate preference with the allozyme cline in a house mouse hybrid zone.

Main Methods:

• Mate odor choice was assessed in male and female mice sampled across the Jutland hybrid zone.
• Urine samples from geographically distant populations, carrying subspecies-specific signals, were used.
• Behavioral data were analyzed using a model of clinal variation and compared to allozyme data.

Main Results:

• Male house mice exhibited assortative mating preferences that shifted abruptly on the Mus musculus musculus side of the hybrid zone.
• No directional preference was detected in females, possibly due to variations in sexual receptivity.
• A genetic model suggested multiple genes and epistasis influence male preference, favoring Mus musculus domesticus-like traits.

Conclusions:

• The study provides insights into the genetic determination of mate preference in mammals.
• Reproductive character displacement in house mice involves complex genetic interactions influencing mate choice.