Sex‐specific inbreeding depression: A meta‐analysis. (21st January 2022)

• Record Type: Journal Article
• Authors: Vega‐Trejo, Regina; de Boer, Raïssa A.; Fitzpatrick, John L.; Kotrschal, Alexander
• Editors: Sánchez‐Tójar, Alfredo
• Is Part Of: Ecology letters. Volume 25:Number 4(2022)
• Page Start: 1009
• Page End: 1026
• Publication Date: 2022-01-21
• Subjects: heterogamous -- homozygosity -- incest -- sexual conflict -- sexual selection; Ecology -- Periodicals; 577
• DOI: 10.1111/ele.13961
• Languages: English
• ISSNs: 1461-023X

Abstract

Abstract: Inbreeding depression, the reduced fitness of the offspring of related individuals, can affect males and females differently. Although a comprehensive theoretical framework describing the causes of sex‐specific inbreeding depression is lacking, empirical evidence suggests that often one sex tends to be more vulnerable than the other. However, the generality, direction, and degree of sex‐specific difference in inbreeding depression remains enigmatic as studies on this topic have reported conflicting results. Here, we conduct a meta‐analysis to test for sex‐specific differences in the magnitude of inbreeding depression. We synthetised 321 effect sizes of experimental studies across 47 species and found a small difference in inbreeding depression between the sexes: females suffered slightly higher inbreeding depression than males. Furthermore, a higher inbreeding coefficient was correlated with higher inbreeding depression. However, there was a large amount of heterogeneity that remained unexplained, even when considering different factors that could affect inbreeding between the sexes, such as sexual size dimorphism, heterogamety, the type of trait measured and whether animals were tested in a stressful environment. As such, we highlight the need to further explore inbreeding depression across different species to determine the occurrence and causes of sex differences to increase our understanding of the evolutionary consequences of sex‐specific inbreeding depression. Abstract : Our meta‐analysis across experimental studies found evidence for general inbreeding depression for both males and females and, although the difference between the sexes was not substantial, females were slightly more sensitive to inbreeding depression than males. Our study highlights the need to further explore the effects of inbreeding depression due to intrinsic biological differences between males and females.