The lizard is a popular choice among reptile pet owners. Their behaviour and natural characteristics allow them to adapt to their environment and coexist with other types of lizards and humans. Most lizards, including iguanas, geckos and chameleons will reach maturity by ten months, which will make it easier to determine if your lizard is a boy or girl. If you are unsure or your lizard's gender, several physical and mental attributes can help you distinguish their sex.
Look at the lizard's physical characteristics regarding the size of the body and head. Female lizards have thinner and longer bodies; compared to males, who have shorter and wider bodies. The size of the boy lizard's head is larger with a square-like shape -- compared to the smaller head size of the girl lizard.
Inspect the underbelly markings and colourings of the lizard. The boy lizard will have brighter colours, in order to attract the girl lizard during breeding season. The girl lizard belly colours do not change throughout the year; and they are generally lighter and more dull, compared to a boy lizard.
Look for a small bulge and femoral pores, where the abdomen meats the tail. The femoral pores are in a V shape and are dark in colour. If the bulge and the femoral pores are visible, the lizard is a male. Female lizards lack the bulge and the femoral pores are not visible, since the colours are much duller.
Pay attention to the behaviours of your lizard. Boy lizards tend to be more active, aggressive and are highly territorial.