Causes of covariation of phenotypic traits among populations
Article first published online: 11 DEC 2002
Journal of Evolutionary Biology
Volume 9, Issue 3, pages 261–276, May 1996
How to Cite
Armbruster, W. S. and Schwaegerle, K. E. (1996), Causes of covariation of phenotypic traits among populations. Journal of Evolutionary Biology, 9: 261–276. doi: 10.1046/j.1420-9101.1996.9030261.x
- Issue published online: 11 DEC 2002
- Article first published online: 11 DEC 2002
- Received 6 April 1994; accepted 17 November 1995.
- Cited By
- Among-population covariation;
- genetic correlation;
- population differentiation;
- quantitative genetics;
- selective covariance
Morphological and life-history traits often vary among populations of a species. Traits generally do not vary independently, but show patterns of covariation that can arise from genetic and environmental influences on phenotype. Covariance of traits may arise at an among-population level when genetically influenced traits diverge among populations in a correlated manner. Genetic correlations caused by pleiotropy and/or gene linkage can cause traits to evolve together, but among-population covariance can also arise among traits that are not genetically correlated. For example, “selective covariance” can arise when natural selection directly causes correlated change in a suite of traits. Similarly, mutation, migration, and drift may also sometimes cause correlated genetic changes among populations. Because covariation of traits among populations can arise by several different processes, the evolution of suites of traits must be interpreted with great caution. We discuss the sources of among-population covariance and illustrate one approach to identifying the sources' using data on floral traits of Dalechampia scandens (Euphorbiaceae).