Translator Disclaimer
1 April 2004 TWELVE YEARS OF CONTEMPORARY ARMOR EVOLUTION IN A THREESPINE STICKLEBACK POPULATION
Michael A. Bell, Windsor E. Aguirre, Nathaniel J. Buck
Author Affiliations +
Abstract

Loberg Lake, Alaska was colonized by sea-run Gasterosteus aculeatus between 1983 and 1988, after the original stickleback population was exterminated. Annual samples from 1990 to 2001 reveal substantial evolution of lateral plate (armor) phenotypes. The 1990 sample was nearly monomorphic for the complete plate morph, which is monomorphic in local sea-run populations; the low plate morph, which is usually monomorphic in local freshwater populations, was absent. By 2001, the frequency of completes had declined to 11%, and lows had increased to 75%. The partial plate morph and two unusual intermediate plate phenotypes were generally rare, but occurrence of the intermediates was unexpected. These intermediate phenotypes rarely occur in other, presumably older, polymorphic populations. When low morphs first appeared, they averaged 6.8 plates per side, indicating that the ancestral plate number of low morphs is high, and their mean has subsequently declined. Contemporary evolution in this population indicates that threespine stickleback adapt to freshwater habitats within decades after invasion from the ocean, and thus phenotypes in most populations are adapted to current conditions.

Michael A. Bell, Windsor E. Aguirre, and Nathaniel J. Buck "TWELVE YEARS OF CONTEMPORARY ARMOR EVOLUTION IN A THREESPINE STICKLEBACK POPULATION," Evolution 58(4), 814-824, (1 April 2004). https://doi.org/10.1554/03-373
Received: 24 June 2003; Accepted: 30 November 2003; Published: 1 April 2004
JOURNAL ARTICLE
11 PAGES

This article is only available to subscribers.
It is not available for individual sale.
+ SAVE TO MY LIBRARY

SHARE
ARTICLE IMPACT
RIGHTS & PERMISSIONS
Get copyright permission
Back to Top