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Title: Parallel shifts of visual sensitivity and body coloration in replicate populations of extremophile fish
Abstract

Visual sensitivity and body pigmentation are often shaped by both natural selection from the environment and sexual selection from mate choice. One way of quantifying the impact of the environment is by measuring how traits have changed after colonization of a novel habitat. To do this, we studiedPoecilia mexicanapopulations that have repeatedly adapted to extreme sulphidic (H2S‐containing) environments. We measured visual sensitivity using opsin gene expression, as well as body pigmentation, for populations in four independent drainages. Both visual sensitivity and body pigmentation showed significant parallel shifts towards greater medium‐wavelength sensitivity and reflectance in sulphidic populations. Altogether we found that sulphidic habitats select for differences in visual sensitivity and pigmentation. Shifts between habitats may be due to both differences in the water's spectral properties and correlated ecological changes.

 
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Award ID(s):
1931657
NSF-PAR ID:
10446424
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley-Blackwell
Date Published:
Journal Name:
Molecular Ecology
Volume:
31
Issue:
3
ISSN:
0962-1083
Page Range / eLocation ID:
p. 946-958
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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