There are two species of land Iguana on the Galapagos Islands, plus a marine Iguana. Land iguanas range in color from yellow, gray, brownish red, to black or a splotchy mixture. Marine iguanas are red and bluish-green and black. Marine iguanas also excrete excess salt so often have crusty white spots on their heads.
The land iguanas eat prickly pear cactus pads and fruit—including the spines!—and other plants. Baby iguanas eat insects. The marine iguana is the world's only sea-going lizard and feeds on marine algae and sea weed. Big males can dive as deep as 40 feet and stay underwater for almost 30 minutes.