QUT ePrints

4000 years of phenotypic change in an island bird: heterogeneity of selection over three microevolutionary timescales.

Clegg, S.M. , Frentiu, F.D., Kikkawa, J. , Tavecchia, G. , & Owens, I.P. (2008) 4000 years of phenotypic change in an island bird: heterogeneity of selection over three microevolutionary timescales. Evolution, 62(9), pp. 2393-2410.

View at publisher

Abstract

Pronounced phenotypic shifts in island populations are typically attributed to natural selection, but reconstructing heterogeneity in long-term selective regimes remains a challenge. We examined a scenario of divergence proposed for species colonizing a new environment, involving directional selection with a rapid shift to a new optimum and subsequent stabilization. We provide some of the first empirical evidence for this model of evolution using morphological data from three timescales in an island bird, Zosterops lateralis chlorocephalus. In less than four millennia since separation from its mainland counterpart, a substantial increase in body size has occurred and was probably achieved in fewer than 500 generations after colonization. Over four recent decades, morphological traits have fluctuated in size but showed no significant directional trends, suggesting maintenance of a relatively stable phenotype. Finally, estimates of contemporary selection gradients indicated generally weak directional selection. These results provide a rare description of heterogeneity in long-term natural regimes, and caution that observations of current selection may be of limited value in inferring mechanisms of past adaptation due to a lack of constancy even over short time-frames.

Impact and interest:

22 citations in Scopus
Search Google Scholar™
19 citations in Web of Science®

Citation countsare sourced monthly from Scopus and Web of Science® citation databases.

These databases contain citations from different subsets of available publications and different time periods and thus the citation count from each is usually different. Some works are not in either database and no count is displayed. Scopus includes citations from articles published in 1996 onwards, and Web of Science® generally from 1980 onwards.

Citations counts from the Google Scholar™ indexing service can be viewed at the linked Google Scholar™ search.

ID Code: 54093
Item Type: Journal Article
Keywords: adaptation, microevolution, silvereyes, island biology
DOI: 10.1111/j.1558-5646.2008.00437.x
ISSN: 0014-3820
Subjects: Australian and New Zealand Standard Research Classification > BIOLOGICAL SCIENCES (060000)
Divisions: Current > QUT Faculties and Divisions > Faculty of Health
Current > Institutes > Institute of Health and Biomedical Innovation
Deposited On: 12 Oct 2012 11:08
Last Modified: 12 Oct 2012 11:08

Export: EndNote | Dublin Core | BibTeX

Repository Staff Only: item control page