Why Do Blue Belly Lizards Do Push Ups?
The Western Fence Lizard, commonly known as the “blue belly lizard” due to the distinctive blue patches on its underside, often exhibits a peculiar “push-up” behavior. This rhythmic motion, frequently observed in sunny habitats, serves as a complex form of communication. This article explores what these displays convey to other lizards.
Decoding the “Push-Up” Display
The “push-up” display performed by Western Fence Lizards is a deliberate physical act involving rhythmic raising and lowering of the body. Lizards achieve this by extending their front limbs, lifting their torso, and often bobbing their head. This motion can vary in intensity and speed, from rapid, vigorous movements to more subtle undulations. The display is a visual signal, making the lizard conspicuous.
These movements are a primary method of communication for lizards, especially since they do not rely on vocalizations. The speed and pattern of the head bobs and push-ups can convey different messages, indicating the lizard’s physical condition or intent. For instance, a faster, more enthusiastic display can signal greater strength and fitness.
The Core Reasons Behind the Behavior
The push-up behavior serves multiple functions for Western Fence Lizards, primarily revolving around territory, mating, and social standing. Males frequently use these displays to assert dominance and warn off rivals from their home ranges. This visual assertion of ownership can often prevent direct physical confrontations, which are costly and risky.
During the breeding season, male lizards use push-ups as a crucial part of their courtship rituals to attract females. By performing these displays, males showcase their health, vigor, and genetic quality. The vibrant blue patches on their bellies and throats become more prominent during these displays, signaling their attractiveness to potential mates. Females tend to be impressed by more enthusiastic and sustained displays, indicating a fitter mate.
Beyond territorial defense and mating, push-ups also help establish and maintain social hierarchies among lizards. This behavior allows lizards to signal their social status to others, indicating who is dominant and who is submissive. These displays contribute to forming stable social structures without constant physical conflict.
Contextual Influences on Lizard Displays
The frequency and intensity of a Western Fence Lizard’s push-up display are influenced by several environmental and social factors. The presence of other lizards significantly impacts display behavior. For example, a male will intensify its display when a rival male enters its territory, aiming to deter the intruder. Conversely, the display might be tailored to attract a receptive female, potentially involving a different pace or emphasis on colored patches.
The breeding season sees an increase in the frequency and vigor of these displays as males compete for mates. Environmental cues also play a role; perceived threats or the presence of predators might trigger a display to communicate alertness. Factors like temperature or the type of surface the lizard is on can influence how and when these displays occur.