Iguanas

Males of most species use head bobbing, pushups, and expansion of the dewlap to attract a mate. More threatening postures, such as opening the mouth, tongue-flicking, and snorting, are added when defending territories or warding off rivals. Banded iguanas also puff up their torso and their green bands become much darker, increasing the contrast with their pale blue-green bands. Physical aggression is rare, and the occasional clash results in head-thrashing, tail-swinging, and sometimes biting, with the loser creeping quietly away. Females usually only show aggression when contesting for, or defending, nesting sites. Each species has a distinct display pattern which seems to aid in recognition.