Within the Genus Iguana there is a large variety and different species vary greatly in size, color, behavior and endangered status in the wild.
The large variety of habitats has led to each species having its own unique adaptations.
Average 8 years in the wild; 15-20 years in captivity, while The San Diego Zoo, which has an excellent breeding program for threatened and endangered species, has documented lifespan of up to 60 years!
The Green Iguana (aka common iguana or American Iguana) is native to Central and South America and the islands of the Caribbean and West Indies. They live high in the trees of tropical rainforests. They have unfortunately become a nuisance in Puerto Rico and parts of the southern US, especially Florida, where they have become an invasive species. Humans of course are responsible for bringing them to these places.
The Green Iguana is a large lizard and the longest of all iguana species growing up to 5-7 feet long (including the tail). They also have very long toes and sharp claws with long tails for balance in the treetops. These whip-like tails can make up more than half of their body length. Despite their name, they can be a variety of colors from vibrant green to red, orange and blue. They have tall spikes extending down their spine and a parietal eye on top of their head. This so-called "third eye" is sensitive to light and sends signals to the pineal gland located deep in the brain which produces melatonin which then helps maintain circadian rhythm ("internal clock"). They also have the distinguishing feature of a large dewlap under the throat, which is more developed in males. Their coloration allows for excellent camouflage in the trees, while the colors of individuals can vary based upon mood, temperature, social status, and health.
Herbivores as adults eating fruits, buds, flowers and leaves; omnivores as young eating small insects in addition to plants. In captivity they require high calcium found mainly in veggies, so Basil and Smaug are fed a salad of dark leafy greens, a variety of fruits, veggies and pellets.
Many natural predators include hawks, owls, snakes, feral cats and dogs and humans - in fact Green iguanas are bred on farms in Central and South America for human consumption!
Basil and Smaug serve as ambassadors for all Iguanas, some of which are very endangered. Threats to their populations in the wild include habitat loss, introduction of exotic animals that prey on them, capture for the pet trade and poaching.