Creationists have long contended that the vertebrate eye is too complex to be a product of evolution. By comparing the structures and embryological development of the eye in vertebrate species, however, researchers have gained key insights into the organ's origin, as this article in the July issue of Scientific American explains. These findings indicate that our camera-style eye has startlingly deep roots, and hint at how it might have functioned before it evolved all of the elements necessary for vision.

» View a slide show of the many kinds of eyes that evolution has produced