Meeting Abstract

77-6   14:45 - 15:00  Does lizard display behavior follow the principles of signal efficacy? Johnson, LE*; Ladner, JT; Singhal, S; Losos, JB; Johnson, MA; Washington University, St. Louis, MO; Northern Arizona University, Flagstaff, AZ; California State University, Dominguez Hills, CA; Washington University, St. Louis, MO; Trinity University, San Antonio, TX lauren@planetjohnson.com

Visual displays in animals can communicate many aspects of individual identity, status, ability, or motivation. Yet, to effectively share information, these displays must be easily detected by their targets (e.g., potential mates or rivals). Male Anolis lizards are known for their flashy, extendable throat fans called dewlaps, which males display primarily in courtship and aggressive encounters with other males. In this study, we test the hypothesis that the dewlap display behaviors of male anoles align with principles of signal efficacy, meaning that dewlaps are displayed in ways that maximize their detection by conspecifics. We collected data on perch visibility, dewlap display frequency, and dewlap size of males of two anole species in their native habitats in Jamaica: “trunk-crown” specialist A. grahami and “trunk-ground” specialist A. lineatopus. We test whether males in more open habitats will display their dewlaps more frequently than males in more cluttered habitats, since open habitats increase the chance of signal detection. We also test whether males with larger dewlaps will display their dewlaps more frequently, as large dewlaps are more detectable than smaller ones. In A. grahami, we found that males perching in more open habitats displayed their dewlaps more frequently than those using more cluttered habitats, but dewlap size and display frequency were uncorrelated. In contrast, A. lineatopus males with larger dewlaps displayed their dewlaps more frequently than those with smaller dewlaps, but habitat structure and dewlap display frequency were uncorrelated. In sum, each species behaved in a way that increased signal efficacy, but the two species utilized different strategies. These findings suggest that principles of signal efficacy may influence how animals use behavioral displays.