2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

y predation risk. However, hunger level affected kin preferences depending on the
body size of the test fish. Small, hungry juveniles avoided to shoal with kin whereas
small, saturated juveniles as well as larger juveniles in general tended to
preferentially shoal with kin. We discuss the results in the context of size-related
energetic demands.
����107 Arndt Wellbrock
To bleed or not to bleed? - Validation of buccal swabs compared to blood as DNA
source for molecular sexing of birds
Author: Arndt Wellbrock 1 , Christina Bauch 1 , Jan Rozman 1 , Klaudia Witte 1
Affiliation: 1 Research Group on Ecology and Behavioral Biology, Section of Biology and
Didactics, Department of Chemistry - Biology, University of Siegen
Buccal swabbing is an easy, non-invasive and alternative method to blood sampling
to get DNA for sexing birds. However, little is known about the reliability of this
sampling method. Here, we investigated the reliability of buccal swabs for molecular
sex determination in very young nestlings (0 to 14 days old) and adults of the
Common Swift (Apus apus) by comparing sex determination based on buccal swabs
and based on blood samples of the same individuals. Thereby, buccal swabbing was
tested for sexing a small non-passerine bird for the first time. We found that buccal
swabs are a reliable non-invasive source of DNA for sex determination in both adult
and very young swifts. In 47 out of 53 (89%) nestlings and 10 out of 11 (91%) adults,
we received enough DNA via buccal swabs for a successfull PCR. Sex determination
based on DNA from buccal swabs matched the result of sex determination based on
blood samples in 46 of the 47 nestlings (98%) and in all 10 cases in adults (100%
matching). Since PCR amplification was performed only once per individual, we
consider this success rate - and hence the reliability of buccal swabs as DNA source -
as very high. Therefore, we recommend buccal swabs as a feasible non-invasive
method in future genetic studies in birds, especially for small nestlings and in species
which are sensitive to stress.
����108 Mareike Wurdack
Consequences of an arms race between a host and its three brood parasites
Authors: M. Wurdack 1 , J. Kroiss 1 , E. Strohm 1 , O. Niehuis 1 , T. Schmitt 1
Affiliation: 1 Universität Freiburg
Parasites and hosts have conflicting interests ? to either exploit or defend. This sets
the board for an evolutionary arms race. The species pair follows a trajectory through
repeated cycles of fine tuning of the parasite?s attack strategies and evasive actions
of the host. Brood parasites in particular need to avoid detection by the host. Insect
brood parasites may avoid olfactory detection by mimicking the host?s cuticular
hydrocarbon (CHC) profile. The arms race would then lead to optimized chemical
mimicry in the parasite. The host could e.g. escape a mimetic match by changing its
CHC composition.
Ordinary parasitic associations consist of one enemy (the parasite) and one target
(the host). But more complex variations are possible, too. In this study, a solitary host
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