Figure 4. Photophobic Responses Result from Light Stimulus.

Graph showing behavioral responses over increasingly attenuated light, as measured by the number of worms in Q4 at 2 minutes. Worms were exposed to full light, 95% attenuated light, and 99% attenuated light (or optical densities of 0, 1.3 and 2.0 respectively). The trend shows that phototactic responses decreased along with diminished behavioral stimuli (light).