ECHOLOCATION, OLFACTION AND FRUIT DISPLAY - HOW BATS FIND FRUIT OF FLAGELLICHOROUS CUCURBITS

1. The relationship between plant morphology and the senses used by di spersal agents to find fruit was examined. 'Flagellichory' (fruit born e on pendulous structures), a costly morphology associated with disper sal by bats, is focused on, 2, Using Gurania spinulosa, a flagellichor ous vine, and its major dispersal agent, Phyllostomus hastatus, the hy pothesis was tested that flagellichory increases the conspicuousness o f fruit to bats that use echolocation to find fruit.3. The responses o f wild-caught P. hastatus to various fruiting branch morphologies and fruit odour were recorded. Phyllostomus hastatus used echolocation rat her than olfaction to detect fruit, and consistently chose fruit displ ayed on pendulous leafless branches, ignoring fruit held among leaves on horizontal branches. s4. By comparing echolocation signals with the distance between fruiting branches of G, spinulosa and surrounding ve getation, it was shown that pendulous fruiting branches present clear, clutter-free targets that can be detected by echolocating bats. This is the first demonstration of neotropical frugivorous bats using echol ocation to find fruit.