(full paper is archived in the Miller Library)
Title: Visual ecology of Tripedalia cystophora (Class Cubuzoa)
Student Author(s): Landfield, Ryan Elliott
Faculty Advisor(s): Thompson, Stuart
Location: Final Papers Biology 175H
Date: June 2000
Abstract: The purpose of my experiments was to test the behavioral response and capabilities of the cubomedusan Tripedalia cystophora to various visual stimuli. My hypothesis was that the cubomedusae would respond more strongly (be more attracted to) color toward the blue end of the visual spectrum as well as to reflective small objects within the water that mimic their food sources. Lab experiments showed that T. cystophora did indeed favor blue light (440 nanometers, 480 nanometers) over red light (700 nanometers) when a tight cone of light of a given color was placed at a the end of a rectangular tank. Green light was intermediately favored (515 nanometers, 540 nanometers) as was violet light (385) nanometers. Experiments also showed that T. cystophora were attracted to long wave Ultra Violet Light (360 nanometers) but not significantly to short wave Ultra Violet (254). Also, in experiments testing preference for texture of the light cone, T. cystophora favored reflective bodies within the light cone (chemically neutral brine shrimp, small T. Cystophora) over only the light cone. A uniform rising movement was also noticed upon the onset of darkness.