When this happens, the thyroid gland is no longer under pituitary control. The amount of hormone it produces is dependent on levels of TSI. TSI are the direct cause of hyperthyroidism in Gravesâ disease and various immune system chemicals known as cytokines also contribute to the symptoms that occur in this disorder.
Confidence votes 20. Female Iguanas will lay eggs when they become sexually mature, which is around 1.5 to 2 years old. They do not need to be fertilized to lay so therefore do not need a male Iguana. They need to be healthy before they lay or else there can be very serious problems.
Raccoons, fish, crows, vultures, feral pigs, and other predators dig up iguana nests and eat the eggs. Raccoons, snakes, hawks, owls, egrets, herons, cats, and dogs kill the majority of hatchling and juvenile iguanas. After young iguanas reach about two feet in length, they have fewer natural enemies.