ULTIMATE FUNCTIONS OF NON-FRUITING FLOWERS IN LATHYRUS-VERNUS

In this study, four hypotheses concerning female function of non-fruiting flowers in a herbaceous perennial legume, Lathyrus vernus, were examined. I found no evidence that surplus flowers serve to increase the opportunities for maternal selection based on offspring quality, or to decrease seed predation by dispersing oviposition of seed predators. However, a proportion of the cost of sur-plus flowers may be counter-balanced by gains from increased pollinator attraction and increased fruit set in years with low pollen availability. Furthermore, surplus distal flowers function as reserve-ovaries if basal flowers are preyed upon or not fertilized. A quantitative model based on the reserve-ovary function predicted half of the surplus flowers actually observed. This study thus suggests that surplus flowers in L. vernus serve several functions simultaneously.