1 March 2009 Temperature-Based Extrinsic Reproductive Isolation in Two Species of Drosophila
Daniel R. Matute, Caroline J. Novak, Jerry A. Coyne
Author Affiliations +

Drosophila santomea and D. yakuba are sister species that live on the African volcanic island of São Tomé, where they are ecologically isolated: D. yakuba inhabits low-altitude open and semiopen habitats while D. santomea lives in higher-elevation rain and mist forest. To determine whether this spatial isolation reflected differential preference for and tolerance of temperature, we estimated fitness components of both species at different temperatures as well as their behavioral preference for certain temperatures. At higher temperatures, especially 28°C, D. santomea was markedly inferior to D. yakuba in larval survival, egg hatchability, and longevity. Moreover, D. santomea females, unlike those of D. yakuba, become almost completely sterile after exposure to a temperature of 28°C, and conspecific males become semisterile. Drosophila santomea adults prefer temperatures 2–3°C lower than do adults of D. yakuba. Drosophila santomea, then, is poorly adapted to high temperature, partially explaining its restriction to cool, high habitats, which leads to extrinsic premating isolation and immigrant inviability. Rudimentary genetic analysis of the interspecific difference in egg hatchability and larval survival showed that these differences are due largely to cytoplasmic effects and to autosomal genes, with sex chromosomes playing little or no role.

© 2009 The Society for the Study of Evolution.
Daniel R. Matute, Caroline J. Novak, and Jerry A. Coyne "Temperature-Based Extrinsic Reproductive Isolation in Two Species of Drosophila," Evolution 63(3), 595-612, (1 March 2009). https://doi.org/10.1111/j.1558-5646.2008.00588.x
Received: 11 June 2008; Accepted: 1 November 2008; Published: 1 March 2009

This article is only available to subscribers.
It is not available for individual sale.

habitat isolation
premating isolation
temperature tolerance
Get copyright permission
Back to Top