The cover photograph demonstrates sexual dimporphism in a flowering plant, Silene latifolia. I made the image while working as a research assistant in Lynda Delph’s lab in the Department of Biology at Indiana University in Bloomington. The

Pictured are the female (left) and male (right) reproductive organs. Notice the extreme differences in size. There is enough genetic variation in many populations of Silene latifolia such one can reduce or expand the degree of dimorphism by artifically selecting on a physical trait such as calyx width or flower number.

Gender and Sexual Dimorphism in Flowering Plants. 1999. M.A. Geber, T.E. Dawson, and L.F. Delph, Eds. Springer, Berlin.