The crab spider Thomisus spectabilis typically forages by ambushing pollinating insects, such as honey bees (Apis
mellifera), on flowers. Flowers attract pollinating insects by a visual signalling system, which could be exploited by
crab spiders in several ways. They may identify profitable foraging patches by recognising the flower signals that
are directed to the insects, and may thus benefit from the fact that insects are unable to associate spatial patterns
and colours with danger, when the same signals are evolved to recognise food rewards. Therefore, the reflection of
crab spider bodies may have evolved to attract pollinators. The spiders may mimic the signalling system of flowers
and exploit the behavioural capabilities of their potential prey.
The proposed project will investigate the signal exploitation by crab spiders incorporating the entire light spectrum
(green and shorter) utilised by spiders and bees. Field studies will describe the patch choice by honey bees and will
relate them to the patch choice of crab spiders. The mechanisms behind these choices will be examined in the
laboratory by highly controlled choice experiments. The proposed study will therefore contribute to our
understanding of the evolution of behavioural interactions between spiders and their insect prey.