, Volume 43, Issue 2, pp 539-547
Date: 14 Mar 2008

Phototactic response and light sensitivity in an epigean and a hypogean population of a barb (Garra barreimiae, Cyprinidae)

Rent the article at a discount

Rent now

* Final gross prices may vary according to local VAT.

Get Access

Abstract

We investigated the response of two populations of the barb Garra barreimiae to different light intensities (0.5–2000 lx) from a light source. Adults of both the surface (epigean) and cave (hypogean) G. barreimiae populations show photophobic behavior. A photophobic response in the cave form was seen only at higher light intensities because the cavefish are eyeless and rely on extra-retinal light receptors to detect light. In contrast, juveniles (surface and cave) showed photophilic behavior, and their preference for the photic zone of the test tank decreased with increasing age. We discuss the potential role played by photophobic behavior for the colonization of caves by previously surface-dwelling fishes.