How fast can a iguana change colors?

Iguanas can change colors relatively quickly, but the exact speed varies depending on the species and the environmental conditions. Typically, they can shift their coloration within minutes to hours as a response to factors like temperature, mood, or stress. This color change occurs through the expansion or contraction of specialized pigment cells in their skin. However, it is not as rapid or dramatic as the color changes seen in some other reptiles, like chameleons.