These western fence lizards, aka “blue bellies” are doing push-up as a mating display, flashing the blue markings on their bellies to attract the females. Their push-ups are also a territorial display, often to challenge other males if they get too near and fight one another when they enter their territory.

Why do lizards bob their heads up and down?

Fast head-bobbing is mainly observed in males. It can indicate aggression, territoriality and dominance. Males will often quickly bob their heads up or down toward younger males and females.

Do female lizards do pushups?

Females and juveniles have some color, but not nearly as bright. ... And although you'll often see both males and females doing push-ups (to regulate body temperature), the males are much more energetic. Push-ups have several purposes, including courtship.