2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

Such an observed change in the searching behaviour of newly emerged N.
vespilloides females could enhance their environmental exploration due to an
increase in their travelled distance. Furthermore, in the advanced decay stage we
registered a significantly higher preference of beetles for upwind directions to its
specific odour plume when compared to the solvent control. Such a change in
walking upwind behaviour could be a pre-condition for the detection of large
cadavers in N. vespilloides burying beetles. Our findings could be of general
importance for applied forensic entomology because newly emerged N. vespilloides
females on large cadavers can and should be regarded as potential indicators of
prolonged postmortem intervals.
�35 Christin Wurmitzer A 702 / 14:30
Olfactory preferences in dung beetles (Scarabaeoidae: Geotrupidae &
Scarabaeidae)
Authors: Christin Wurmitzer 1 , Belén Maldonado 2 , Kai Dworschak 3 , Federico Ocampo 2 ,
Nico Blüthgen 3 , Thomas Schmitt 1
Affiliations: 1 Department of Evolutionary Biology and Animal Ecology, Faculty of
Biology, Albert-Ludwigs-University Freiburg; 2 Instituto Argentino de
Investigaciones de las Zonas Áridas, CCT-CONICET, Mendoza, Argentina;
3 Ecological Networks, Faculty of Biology, TU Darmstadt
Adult dung beetles as well as their offspring feed on the excrement of vertebrates, a
feeding habit which is defined as coprophagy. Feces are a rare and highly
unpredictable resource which is available for short times only. Therefore a
coprophagous insect’s chance of encountering an adequate food source should be
higher for polyphagous feeders than for specialists. Thus coprophagous Scarabaeidae
are regarded as polyphagous. However, there is evidence for preferences for feces
produced by vertebrates with certain dietary habits, e.g. herbivores, by some beetle
species. Nevertheless these dung beetles are not specialized. To locate dung, adult
beetles rely on olfactory cues. Earlier studies proved that excrements are chosen in
response to their volatiles. Yet it remains undetermined which volatile substances
from the headspace of dung act as attractants for coprophagous beetles and what
the function of the volatiles for the beetles’ preferences is. For my study, I chose four
volatiles for which an attractive effect on dung beetles has been hypothesized. A
comparison of the attractive effect on dung beetles was conducted using pitfall traps
baited with different types of dung and different combinations of these four volatiles.
Fieldwork took place in Argentina, Austria and Germany. We found that while single
substances as well as mixtures do lure dung beetles, their level of attractivity varies.
Furthermore, the level of specialization of species was compared by means of
network analysis and a higher level of specialization was found for the Argentinian
dung beetle fauna compared to the Austrian one.
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