"Development, Plasticity and Evolution of Butterfly Eyespot Patterns" (1996), by Paul M. Brakefield et al.

Paul M. Brakefield and his research team in Leiden, the Netherlands, examined the development, plasticity, and evolution of butterfly eyespot patterns, and published their findings in Nature in 1996. Eyespots are eye-shaped color patterns that appear on the wings of some butterflies and birds as well as on the skin of some fish and reptiles. In butterflies, such as the peacock butterfly Aglais, the eyespots resemble the eyes of birds and help butterflies deter potential predators. Brakefield's research team described the stages through which eyespots develop, identified the genes and environmental signals that affect eye-spot appearance in some species, and demonstrated that small genetic variations can change butterfly eyespot color and shape. The research focused on a few butterfly species, but it contributed to more general claims of how the environment may affect the development of coloration and how specific color patterns may have evolved.