social but not solitary bees reject dangerous flowers where a conspecific has recently been attacked...
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
Social Solitary
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
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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