Color change refers to the alteration of the color of an object or substance due to various factors. This can occur through physical processes, such as heating or cooling, or chemical reactions, like oxidation. For example, when iron rusts, it changes from a metallic gray to a reddish-brown color. In nature, color change is often seen in chameleons, which can shift their skin color for communication or camouflage. Additionally, some flowers change color as they age, attracting different pollinators. These changes can serve important functions in survival and reproduction within ecosystems.