ABSTRACT
The view that herbivory has a negative impact on plant fitness is supported by numerous studies. Two important aspects of the responses which may shed light on the possibility that plant-herbivore interactions are mutualistic have yet to be adequately addressed. First, the degree to which responses to herbivory are a result of herbivore selection pressures is unknown. Second, the degree to which these responses offset losses in fitness, as measured by the number of offspring produced, is rarely determined. The chapter addresses these two aspects of plant responses to herbivory using the interactions of members of the Apiaceae and their flower-feeding herbivores as a model system. To determine the effects of floral herbivory on fitness, the number of offspring recruited from primary, secondary and tertiary seeds were monitored. Finding show that Pastinaca and Heracleum suffer significant and predictable floral damage in nature, suggesting that disruption of normal developmental patterns rather than herbivory determines a species’ ability to respond to damage.
