It's scientific name is Danaus plexippus. The reason why it has it's bright color is to warn predators of its bad taste.
The egg is only found on species of Milkweed, which is also known as the host plant. It leaves cone-shaped, ivory-colored eggs on the host plant. It's Nectar plants are Milkweed, Asters, Red Clover, Zinnia, Cosmos, Lantana, Pentas, and Daisies. It's cocoon is green, smooth, dotted with gold, and crowned with a gold circle. As a caterpillar it is white with yellow and black stripes and it is about two inches. It's average wingspan is 4-6 inches.