The Occurrence and Ecological Significance of Color Responses in Some Marine Crustacea

Abstract

(1) Specific dances in response to red and blue light have been found in ten species of marine planktonic Crustacea including copepods, decapods, and stomatopods. A red dance involves relatively little activity and predominantly vertical movements while a blue dance involves greater activity and predominantly horizontal movements. (2) In general dancing forms tended to be more sensitive to red light than non-dancers. (3) Since only two species showed vertical movement with a spectral shift, slight upswimming with a shift toward red, color responses would seem to play little or no role in vertical migration. (4) Color responses, logically enough, do not occur in forms which enter the plankton only at night. Their absence in other zooplankters remains unexplained. Maturity and physiological state appear to be factors affecting them in those forms in which they occur only part of the time. (5) The function of color dances, where they occur, seems to be to assure the collection of a population in areas wher...