Central and South America; introduced on some Pacific islands, tropical areas such as the Florida Keys
It is arboreal, living in rain forests and surrounding areas, often near river banks.
The green iguana's teeth are finely serrated, numerous, and closely set. It has a thick, mobile, lightly forked tongue with which it "blots" in order to smell-taste. The eyes have round pupils. The eyesight is surprisingly good, and it can probably see colors. There is a high crest along the back which recesses toward and on the tail. This animal has a gular pouch and a serrated dewlap (for display) below the neck. The large powerful clawed feet with outer toes opposed help in climbing trees. The tail can fracture but not "slip" off as is the case with many of the smaller lizards. The coloring usually fades from the bright green of the young iguanas to a dull gray-green or yellow-green as they grow older. Sexes are difficult to determine in young iguanas. As they mature, males develop larger cheek jowls and femoral pores (under the legs at the base of the tail). Dorsal crests and the enlarged scale beneath the ears usually grow larger on the males than on the females.
The green iguana is timid and considered harmless unless it is frightened or excited; then it can use its tail as an effective whip and its claws to scratch, and it has been known to draw blood when it bites. It seems to prefer to climb to the top of the canopy of the trees, probably for better vision of the surroundings and basking in the sunlight. A common green iguana can spend long periods of time submerged in a stream or pond and can sleep underwater for an hour or more. This and its agile swimming ability make it a remarkable lizard.
When the female is ready to lay her eggs she digs a shallow trench in moist ground or decaying vegetation, deposits 20-72 eggs in the trench, then covers the eggs and leaves them to incubate. Eggs will not incubate if the temperature is a few degrees too high or too low. The young hatch in 4-6 weeks. Soon after emerging from the eggs, the 6 inch long hatchlings scatter, climbing into the trees.