It is often hard to tell the sex of juvenile iguanas until these characteristics develop. Another way to identify sex when iguanas are older is by examining their femoral pores, which are much different between sexes. During breeding months, secretory activity peaks, and at that time dominant breeding males produce more secretion than subordinates and females. Juvenile males that preform visual displays have significantly larger pores than those who do not display. Because of this, it is believed that there is a relationship between social dominance and androgen levels.
Femoral pores are also a good way to identify related species.
Related species have secretions that are more similar than distantly related species. The iguana's diet lies somewhere along a carnivory, omnivory, herbivory continuum, and fluctuates along that continuum depending on factors such as season, size, and resource availability. For the most part, in the wild, Iguana iguana is herbivorous. The green iguana spends most of its activity cycle resting, not feeding and foraging like other carniverous lizards. When foraging, the iguana returns to the same foraging site day after day.