Low Illumination visual capabilities of the Red-backed Salamander, Plethodon cinereus.
Mark Nelson (Senior, 2015), Jon Treen (Senior, 2015), and Bryant Buchanan. 2014-2015.
Red-backed salamanders are important model organisms in the study of the evolution of behavior and ecological interactions. These salamanders are nocturnal and are important components of the forest floor ecosystem in the Northeastern United Sates. However, little is known about their ability to use vision at the low illuminations at which they are normally active. Based on the complexity of visual displays and visual interactions during territorial encounters and mating and the use of vision during foraging we hypothesize that these salamanders are capable of using vision even at the low environmental illuminations at which they are normally active at night. We are evaluating the ability of salamanders to detect moving, high contrast prey at normal nocturnal illuminations ranging from 0.00005 lx (starlight) to 0.005 lx (full moonlight). We have designed an apparatus that allows us to constistently present moving artificial prey stimuli to the salamanders at a variety of illuminations to assay the ability of the salamanders to detect the stimuli using vision alone. The information acquired in this study will be used by behavioral ecologists to understand how, when, and where vision might be used in territorial, predatory, and courtship behaviors.