ALTERNATIVE ROUTES TO THE EVOLUTION OF COMPETITIVE ABILITY IN TWO COMPETING SPECIES OF DROSOPHILA

Amitabh Joshi; John N Thompson

doi:10.1111/j.1558-5646.1995.tb02298.x

ALTERNATIVE ROUTES TO THE EVOLUTION OF COMPETITIVE ABILITY IN TWO COMPETING SPECIES OF DROSOPHILA

Evolution. 1995 Aug;49(4):616-625. doi: 10.1111/j.1558-5646.1995.tb02298.x.

Authors

Amitabh Joshi¹, John N Thompson²

Affiliations

¹ Department of Genetics and Cell Biology, Washington State University, Pullman, Washington, 99164.
² Departments of Zoology and Botany, Washington State University, Pullman, Washington, 99164.

PMID: 28565141
DOI: 10.1111/j.1558-5646.1995.tb02298.x

Abstract

The evolution of components of interspecific competitive ability was examined in three different environments for three replicate pairs of Drosophila melanogaster and D. simulans populations. Populations evolved enhanced competitive ability in three ways: (1) increased effectiveness at reducing the numbers of the competitor species; (2) increased resistance to the inhibitory effects of the competitor species; or (3) a combination of the two. Considerable variation was seen in the evolutionary outcomes of competition among environments, and also among replicate populations within environments. Significant replicate-by-environment interactions were also observed. The results suggest that the evolutionary routes to the evolution of enhanced competitive abilities can potentially differ among subdivided populations, creating a geographic mosaic of outcomes.

Keywords: Competitive ability; Drosophila; geographic structure; variable outcomes.