Sex-specific floral attraction traits in a sequentially hermaphroditic species

The examination of sexual dimorphism in plants has primarily been restricted to dioecious taxa. However, most angiosperms produce cosexual flowers in which male and female function are separated temporally, which may also generate sexual dimorphism (between the male and female stages of floral lifespan). The temporal separation between male and female function in such flowers may be associated with variation in traits that influence pollinator attraction and may function to minimize self-fertilization or to maximize sex-specific fitness.

In this study, we describe variation in floral color, pattern and size across discrete functional sex stages within flowers, and between individuals of Clarkia unguiculata (Onagraceae).  In addition, we examine the effects of these floral traits on pollen receipt (female fitness).

We use a combination of photographic techniques and image analysis to measure floral attributes in 225 greenhouse grown individuals across stages of floral development a...