Prickly pear is also known as the pear cactus. It belongs to the Cactaceae family of cactus. It is a flowering plant that bears flowers of all different colors, but are commonly yellow. The flowers will turn into a fruit that is sometimes referred to as tuna. The color of this fruit can be red, green, or yellow orange. Different species of the prickly pear genus can be found throughout the world, from the Mediterranean to the United States and from Mexico to the Galapagos. In the Galapagos, the famed tortoises that live there eat the fruit as a primary source of food.