Behavioral evidence for intraspecific signaling with achromatic and polarized light by cuttlefish (Mollusca: Cephalopoda)

Abstract

AbstractIntraspecific visual communication was studied quantitatively by testing the behavior of Sepia officinalis, the common cuttlefish, as senders and receivers of body pattern signals. These signals can be achromatic and/or linearly polarized and are produced by specialized dermal cells. Experiment 1 addressed whether the presence of conspecifics affected the visible, achromatic body patterns of males. These patterns tended to vary among conditions, suggesting limited sensitivity to audience. One set of body patterns varied with the number of conspecifics viewed while an uncorrelated set of body patterns varied with the sex of conspecifics viewed. Males showed high-contrast zebra banding when viewing another male, supporting previous studies of body patterns in male-male agonistic behavior. Experiment 2 addressed the relationship of polarized light patterns with visible body patterns of males and females, and tested whether senders modified their polarization patterns in response to conspecifics. Polarization patterning was only weakly associated with visible body patterns. Females showed more polarized body patterns than did males, but polarized patterns did not differ among conditions; thus, no sensitivity to audience by senders was found. Experiment 3 addressed whether conspecific receivers used information from polarized body patterns. Limited evidence was found for changes in the behavior of female but not male observers, suggesting that female receivers may use polarized patterns as a source of information about conspecifics. The information contained in polarization patterning may complement that contained in zebra patterning such that both males and females advertise their species, sex, location, and size to conspecific receivers.