Abstract
Previous studies of the lizard Anolis sagrei have shown that males in a series of copulations exhibit a significant alternating pattern of mounting behavior and hemipenis use and that this behavior may be adaptive by increasing sperm transfer. To investigate the role sensory feedback from the hemipenis may play in maintaining this alternation of mounting behavior and hemipenis use, the effects of preventing intromission, interrupting copulation, and controlling which hemipenis is used were examined. Males that were allowed to mount, but not to intromit in the first of two successive matings, or bilaterally hemipenectomized males that were allowed to complete four matings, did not exhibit significant alternation of mounting behavior. Significant alternation of hemipenis use was exhibited by males that were allowed to intromit but were interrupted in copulation immediately after intromission. Males that were allowed to intromit but were forced in the first of two copulations to use either the left hemipenis, the right hemipenis, or the hemipenis that was used in an earlier copulation did not exhibit significant alternation of hemipenis use. These results suggest that the alternation of male mounting behavior and hemipenis use observed in A. sagrei is dependent on a hemipenis being intromitted and which hemipenis is used, but is independent of copulation duration.