SEX POLYMORPHISM IN SILENE ACAULIS (CARYOPHYLLACEAE) AND THE POSSIBLE ROLE OF SEXUAL SELECTION IN MAINTAINING FEMALES

摘要: Pollen accumulation rates and their relationship to stigma morphology pollinator visitation behavior were compared between female hermaphrodite sex morphs of the alpine plant Silene acaulis var. subacaulescens (Caryophyllaceae). Although stigmas perfect flowers collected comparable pollen loads, became receptive earlier in anthesis therefore recruited a larger number tubes. Together with early receptivity young had stigmatic area longer papillae than did flowers. Pollinator also differed morphs, bumble bees spending more time probing Differences schedules have consequences for different opportunities sexual selection two morphs. Female flowers, by providing effective gametophytic screen, potential produce higher quality offspring. This is proposed as further compensatory advantage maintaining females, single fitness function, populations containing hermaphrodites which both male functions.