The evolution of infertility: does hatching rate in birds coevolve with female polyandry?
Article first published online: 21 AUG 2002
Journal of Evolutionary Biology
Volume 15, Issue 5, pages 702–709, September 2002
How to Cite
Morrow, E. H., Arnqvist, G. and Pitcher, T. E. (2002), The evolution of infertility: does hatching rate in birds coevolve with female polyandry?. Journal of Evolutionary Biology, 15: 702–709. doi: 10.1046/j.1420-9101.2002.00445.x
- Issue published online: 21 AUG 2002
- Article first published online: 21 AUG 2002
- Received 6 March 2002;revised 1 May 2002;accepted 7 June 2002
- extrapair paternity;
- genetic incompatibility;
- hatching success;
- sexual conflict
Natural levels of infertility in many taxa are often remarkably high, amounting to a considerable fitness cost which one expects to be minimized by natural selection. Several mechanisms have been proposed as potential causes of infertility, including inbreeding depression, genetic incompatibilities and selfish genetic elements. Infertility may also be an inherent result of conflict over fertilization between the sexes in polyandrous species, either because too many sperm enter the egg or because of over-efficient barriers to such polyspermic fertilizations. We generated phylogenetic independent contrasts to examine the variation in hatching success for a maximum of 58 species of birds in relation to two measures of female polyandry. Hatching success varied enormously across species (range: 61–100%), with a mean of 12% of eggs failing to hatch, but was not related to either the rate of extrapair paternity or to relative testes size. Thus, the causes of this significant fitness cost remains unclear and merits further examination by evolutionary biologists.