High reproductive skew in tropical hover wasps

Area of Science:

• * Social behavior and reproductive strategies in animal societies.
• * Insect social dynamics and evolutionary biology.

Background:

• * Models exploring genetic and environmental factors influencing reproductive partitioning (skew) in animal societies are abundant.
• * Empirical data on reproductive skew remains notably scarce across various species.

Purpose of the Study:

• * To empirically estimate reproductive skew in the Malaysian hover wasp, Liostenogaster flavolineata.
• * To investigate factors contributing to high reproductive skew in a social insect species with small group sizes.

Main Methods:

• * Microsatellite loci were utilized to assess genetic relatedness and estimate reproductive skew.
• * Thirteen nests of Liostenogaster flavolineata were analyzed to quantify egg-laying contributions.

Main Results:

• * Reproductive skew was uniformly high across all analyzed nests, with dominant females laying the vast majority of eggs.
• * On 11 out of 13 nests, a single dominant female laid all female eggs.
• * Likelihood analysis indicated that dominant females also laid approximately 90% of male eggs, with slight variations possibly linked to relatedness.

Conclusions:

• * High reproductive skew in Liostenogaster flavolineata is likely driven by strong ecological constraints.
• * The potential for subordinates to inherit the dominant's position may also contribute to the observed high skew.
• * Findings provide crucial empirical data on reproductive skew in social insects, complementing theoretical models.