Summary
From previously published demographic data of the age distributions and reproductive rates of the pale, intermediate and dark phenotypes of the Arctic Skua, revised estimates are obtained of the intrinsic rates of increase and selective coefficients of the phenotypes in each sex. Two significant components of selection are variation in age of maturity and variation in reproductive success. Sexual selection is a component of the variation in reproductive success. Dark and intermediate birds have a greater reproductive success than pales, partly as a result of their advantage in sexual selection. Pale birds have an overall advantage, however, because they are younger when they first breed. Given the estimated selective coefficients, a computer model predicts that pale birds will gradually replace the others. So far there are not enough data collected over a sufficiently long time to test the model rigorously.
Similar content being viewed by others
Article PDF
References
Cavalli-Sforza, L L, and Bodmer, W F. 1971. The Genetics of Human Populations. W. H. Freeman and Co., San Francisco.
Dublin, L I, and Lotka, A J. 1925. On the true rate of natural increase. J Amer Stat Ass, 20, 305–339.
O'Donald, P. 1976. Mating preferences and their genetic effects in models of sexual selection for colour phases of the Arctic Skua. Population Genetics and Ecology, ed. Karlin, S., and Nevo, E. Academic Press, New York.
O'Donald, P, and Davis, J W F. 1975. Demography and selection in a population of Arctic Skuas. Heredity, 35, 75–83.
O'Donald, P, Wedd, N S, and Davis, J W F. 1974. Mating preferences and sexual selection in the Arctic Skua. Heredity, 33, 1–16.
Pielou, E C. 1969. An Introduction to Mathematical Ecology. John Wiley and Sons, New York.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
O'Donald, P., Davis, J. A demographic analysis of the components of selection in a population of Arctic Skuas. Heredity 36, 343–350 (1976). https://doi.org/10.1038/hdy.1976.41
Received:
Issue Date:
DOI: https://doi.org/10.1038/hdy.1976.41
This article is cited by
-
Mating preferences and sexual selection in the Arctic Skua
Heredity (1977)