2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

Chair: Kathrin Lampert
�33 Hannah Burger A 702 / 14:00
An arthropod deterrent attracts a specialized bee to its host plants
Authors: Hannah Burger 1 , Stefan Dötterl 1 , Christopher M. Häberlein 1 , Stefan Schulz 1 ,
Manfred Ayasse 1
Affiliation: 1 University of Ulm, Institute of Experimental Ecology
Oligolectic bees are specialized on few closely related plant species for pollen
foraging. At the beginning of the flight season newly emerged, naïve females have to
find and recognize their specific host-plants to reproduce successfully.
To investigate the importance of floral cues for host-plant finding and recognition in
oligolectic bees, we chose Hoplitis adunca (Megachilidae), a solitary bee species
which is highly specialized on the flowers of Echium spp. (Boraginaceae). We
hypothesized H. adunca to use Echium-specific signals to recognize their host-plants.
To test the hypothesis, we used a combination of chemical (GC-MS) and
electrophysiological (GC-EAD) analyses, spectral reflection measurements and
bioassays.
Our investigations showed that the interplay between visual and olfactory cues of
Echium flowers is essential for host-plant finding and recognition by H. adunca
females. Colour cues of the flowers attract the bees, while the olfactory cues, which
are highly specific floral scent compounds only known from the host-plants of H.
adunca and as arthropod deterrent, are used by the bees to recognise their host
plant and discriminate it from non-host plants.
Burger, H., Dötterl, S. & Ayasse, M. 2010. Host-plant finding and recognition by visual and olfactory
floral cues in an oligolectic bee. Funct. Ecol., 24: 1234-1240.
Burger H., Dötterl S., Häberlein C.M., Schulz S. & Ayasse M. 2012. An arthropod deterrent attracts
specialised bees to their host plants. Oecologia 168: 727-736
�34 Christian von Hoermann A 702 / 14:15
The attraction of newly emerged Nicrophorus vespilloides females (Coleoptera:
Silphidae) to odour bouquets of large cadavers (Sus domesticus) in different stages
of decomposition
Authors: Christian von Hoermann 1 , Sandra Steiger 1 , Josef K. Müller 1 , Manfred Ayasse 1
Affiliation: 1 Institute of Experimental Ecology, University of Ulm
The burying beetle Nicrophorus vespilloides (Coleoptera: Silphidae) feeds and
reproduces on small carcasses which are buried under the ground as food for their
offspring. For a long time it has been postulated and confirmed that large cadavers
(too big for burying) are important food sources especially for newly emerged
females. Therefore, in a forensic chemo-ecological approach, we have investigated a
potential preference of newly emerged N. vespilloides females for odour bouquets of
piglet cadavers in five different stages of decomposition (fresh, bloated, postbloating,
advanced decay and dry remains). Analyses of walking tracks on a Kramer
sphere inside a constant air stream revealed significantly higher mean walking speeds
of beetles when odour plumes of the decomposition stages post-bloating, advanced
decay or dry remains were applied in comparison to the solvent control, respectively.
56