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Related Experiment Video

Updated: Jun 24, 2026

Manipulation of Ploidy in Caenorhabditis elegans

Manipulation of Ploidy in Caenorhabditis elegans

Published on: March 15, 2018

Sexually antagonistic chromosomal cuckoos.

William R Rice¹, Sergey Gavrilets, Urban Friberg

¹Department of Ecology, Evolution and Marine Biology, University of California, Santa Barbara, CA 93106, USA. rice@lifesci.ucsb.edu

Biology Letters

|April 15, 2009

Summary

Sibling competition drives sex chromosomes to harm siblings lacking them, impacting gene evolution. This study quantifies this selection and its role in sex chromosome decay.

Area of Science:

Evolutionary biology
Genetics

Background:

Sex chromosomes (X, Y or Z, W) are inherited unequally among siblings.
Genes on these chromosomes can lead to sibling conflict due to differing relatedness.

Purpose of the Study:

To quantify and contrast selection pressures on X and Y (or Z and W) sex chromosomes.
To propose a hypothesis for how this selection contributes to non-recombining sex chromosome decay.

Main Methods:

Comparative analysis of sex chromosome transmission and sibling interactions.
Modeling of selection pressures acting on sex-linked genes.

Main Results:

Sex chromosomes are selected to harm siblings that do not carry them, analogous to brood parasitism.

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Quantification of differing selection intensities on different sex chromosomes.

Conclusions:

Sibling competition is a significant evolutionary force shaping sex chromosome evolution.
This inter-locus sexual conflict provides a mechanism for the degeneration of non-recombining sex chromosomes.