Meeting Abstract

95.1  Sunday, Jan. 6  Staged territorial intrusions and aggressive visual signaling in males of three Sceloporus lizard species that differ in abdominal patches HEWS, DK*; VITAL, C; ZÚÑIGA-VEGA , JJ; MARTINS, EP; Indiana State University; Universidad Autonoma de Ciudad Juarez, México; Universidad Nacional Autónoma de México; Indiana University

As in many animals, Sceloporus lizards use multicomponent visual signals involving color and motion. Most Sceloporus are sexually dichromatic: only males have paired blue abdominal patches and use posture to emphasize the abdominal color during male-male aggression. However, there are several independent evolutionary losses or reductions of the blue belly patches in Sceloporus. We examined behavioral responses of males to standardized staged territorial intrusions (STIs), in two white-bellied Sceloporus species, which also differ in lineage age (S. virgatus “recent white”, S. siniferus “older white”), and in a third species with partially-blue abdominal patches and which is in a relatively old lineage (S. merriami “older partial blue”). Previous work found that male S. virgatus (recent white) were less likely to escalate to using aggressive visual displays in standardized STIs compared to males of a blue-bellied species, S. jarrovii. Here we report that male virgatus (recent white) were more likely to use broadcast displays (push-ups) and less likely to use more aggressive displays (“fullshow”, “fullshow hold”). By contrast, males in both siniferus (older white) and merriami (older partial blue) were less likely to use broadcast displays (push-ups) and more likely to use highly aggressive postures (full show), although usually only after moving towards the intruder male. We discuss these species differences in use of broadcast display versus high-intensity aggressive display in the context of considering differences in habitat complexity and in the risk of predation.