Presentation on theme: "SOCIAL BUT NOT SOLITARY BEES REJECT DANGEROUS FLOWERS WHERE A CONSPECIFIC HAS RECENTLY BEEN ATTACKED Llandres, A.L., Gonzalvez, F.G., & Rodriguez-Girones,"— Presentation transcript:
SOCIAL BUT NOT SOLITARY BEES REJECT DANGEROUS FLOWERS WHERE A CONSPECIFIC HAS RECENTLY BEEN ATTACKED Llandres, A.L., Gonzalvez, F.G., & Rodriguez-Girones, M.A.
Social vs. Solitary Bees Related bees live together Infertile females Division of labor A. mellifera, A. dorsata, A. florea, B. terrestris Bees are isolated All females fertile Builds own nest N. strigata SocialSolitary
Introduction Animals rely on cues to avoid predators Avoiding flowers with crushed conspecifics Two types of cues produced by prey By-products of predation Alarm signals 2-heptanone 2-methylbutyl
Alarm Signals 2 hypothesized functions: Signals nectar depletion (Balderrama, 1996) Increases efficiency Marks dangerous flowers Both social and solitary bees respond to volatile cues Social bees are less wary
Questions Do bees mark visited flowers to increase efficiency? Do solitary bees use alarm signals? No studies for the presence of alarm signals in solitary bees.
Methods Inflorescence: a cluster of flowers on one stem Assigned randomly Experimental Control Experimental: bees grasped over the thorax Control: bees visit flower and leave
Methods Record number of bees after that rejecting or visiting the flower Rejection: Bee hovers, then leaves. Accept: Bee hovers and lands. All conducted during sunny weather Tested social bees and solitary bees
Methods Experiments in six geographical locations Baza, Spain Almeria, Spain Vulluercas-Ibores, Spain Cannonvale, Australia MacRitchie Reservoir Park, Singapore Xishuangbanna, China Trials conducted as far away as possible Experimental: 233, Control: 236
***: Social Bees (P<.0001) NS: Solitary Bees (P>0.25) Probability of landing vs. Bee species
Discussion Social bees release alarm signals to warn of predators Treatment had a strong effect on social bees relative to solitary bees Solitary bees do not release alarm signals Limitations: All tests were not run at the same place, at the same time. Different plant species