Variation in Response to Artificial Selection for Light Sensitivity in Guppies (Poecilia reticulate)

Authors

John A. Endler, Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California 93106
Alexandra Basolo, University of Nebraska - LincolnFollow
Stan Glowacki, Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California 93106
Julianne Zerr, Department of Ecology, Evolution, and Marine Biology, University of California, Santa Barbara, California 93106

Document Type

Article

Date of this Version

7-2001

Comments

Published in Am. Nat. 2001. Vol. 158, pp. 36–48. Copyright © 2001 by The University of Chicago. 0003-0147/2001/15801-0003$03.00. Used by permission.

Abstract

We performed artificial selection on the visual system in guppies (Poecilia reticulate), using the optomotor reaction threshold as the selection criterion. Two lines were selected for increased sensitivity to blue light, two were selected for increased sensitivity to red light, and two were unselected controls. There was significant response to selection in all four selected lines and significant heritability for sensitivity. An examination of the spectral sensitivity function showed that the form of the response differed between the red and blue lines and among the red lines. Such divergence is likely because there are many different mechanisms allowing response to selection for spectral sensitivity. Diverse mechanisms allow a divergent response by different populations to the same selective pressures. Such a mechanism can promote diversity in vision and visual signals, and any multicomponent system where different components can respond to the same selective regime.