Intraspecific variability of bite force in Achala copper lizard in a sexual selection context: who bites harder and when and why?

NARETTO, SERGIO; CABEZAS CARTES FACUNDO; LOPEZ JURI, GUADALUPE; CHIARAVIGLIO, MARGARITA

BIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY

WILEY-BLACKWELL PUBLISHING, INC

Año: 2022

0024-4066

Bite force in lizards is involved in key behaviours such as intrasexual agonistic and intersexual interactions. The relationship between morphology and function is dynamic and sexual pressures can affect bite performance differently between sexes, especially considering the biting position and temporal changes related to the reproductive cycle. Achala copper lizard (Pristidactylus achalensis) is a highly dimorphic lizard with a short reproductive season. Both sexes present several bite scars; however, scars? position varies between sexes implying different bite functions. We studied factors influencing bite force such as sex, body size, head morphology, and seasonality. We also compared the maximum bite force at two biting positions (frontal and lateral) related to different behaviours (copulation and fighting), and quantified the incidence and scar pattern between sexes. Overall, males bite stronger than females and lateral bites were stronger than frontal ones. While bite force did not vary seasonally in males, bite force in females decreased after the reproductive period. Stronger bites may confer advantages in mating competition related to the body size in males, while females may benefit from seasonal enhancement of bite force for mate rejection in case of unwanted copulation.