Arnold Library

Reverse evolution of armor plates in the threespine stickleback.

Kitano, Jun and Bolnick, Daniel I and Beauchamp, David A and Mazur, Michael M and Mori, Seiichi and Nakano, Takanori and Peichel, Catherine L (2008) Reverse evolution of armor plates in the threespine stickleback. Current biology : CB, 18 (10). pp. 769-774. ISSN 0960-9822

[thumbnail of Complete manuscript]
Text (Complete manuscript)
Available under License Creative Commons Attribution Non-commercial No Derivatives.

Download (8MB) | Preview
Article URL:


Faced with sudden environmental changes, animals must either adapt to novel environments or go extinct. Thus, study of the mechanisms underlying rapid adaptation is crucial not only for the understanding of natural evolutionary processes but also for the understanding of human-induced evolutionary change, which is an increasingly important problem [1-8]. In the present study, we demonstrate that the frequency of completely plated threespine stickleback fish (Gasterosteus aculeatus) has increased in an urban freshwater lake (Lake Washington, Seattle, Washington) within the last 40 years. This is a dramatic example of "reverse evolution,"[9] because the general evolutionary trajectory is toward armor-plate reduction in freshwater sticklebacks [10]. On the basis of our genetic studies and simulations, we propose that the most likely cause of reverse evolution is increased selection for the completely plated morph, which we suggest could result from higher levels of trout predation after a sudden increase in water transparency during the early 1970s. Rapid evolution was facilitated by the existence of standing allelic variation in Ectodysplasin (Eda), the gene that underlies the major plate-morph locus [11]. The Lake Washington stickleback thus provides a novel example of reverse evolution, which is probably caused by a change in allele frequency at the major plate locus in response to a changing predation regime.

Item Type: Article or Abstract
Additional Information: Not eligible for PMC deposit. See for Author Right's.
DOI: 10.1016/j.cub.2008.04.027
PubMed ID: 18485710
Keywords or MeSH Headings: Adaptation, Biological; Animals; Ecosystem; Ectodysplasins/genetics; Evolution; Gene Flow; Predatory Behavior; Selection (Genetics); Smegmamorpha/anatomy & histology/genetics; Trout; Washington;
Subjects: Cellular and Organismal Processes > Evolution
Organisms > Model organisms
Depositing User: Library Staff
Date Deposited: 29 Sep 2008 23:08
Last Modified: 14 Feb 2012 14:42

Repository Administrators Only

View Item View Item