2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

����67 Danon Clemes Cardoso
Terrestrial gene flow along the southern Brazilian coast: Phylogeopgraphy and
genetic diversity of the endemic sand dune ant Mycetophylax simplex
Authors: Danon Clemes Cardoso 1 , Maykon Passos Cristianno 1 , Mara Garcia Tavares 1 ,
Christoph Schubart 2 , Jürgen Heinze 2
Affiliations: 1 Programa de Pós-graduação em Genética e Melhoramento,
Universidade Federal de Viçosa, Minas Gerais, Brazil; 2 Institut für Zooologie,
Biologie I, Universität Regensburg
The Brazilian Atlantic Forest (Mata Atlântica) presents a wide range of vegetation
types with conspicuous changes across landscapes that include open habitats
covered predominantly by herbaceous and shrubby plants which develop on marine
deposits, so called Restinga. Even with an increasing number of phylogeographic
studies in the past few years, very little is known about the evolutionary history of
the Atlantic Forest. Many species associated with wet forest environments have been
used to infer the evolutionary process that occurred during the last glacial maximum
(LGM) in the Atlantic Forest, but little work focused on organisms associated with dry
environments. Mycetophylax simplex is a small ‘basal’ Attini ant (Formicidae:
Myrmicinae) endemic to sand dunes environment along the Brazilian coast occurring
from southern São Paulo State to Rio Grande do Sul. This species has never been
found living outside of these dry sand dunes, making it a good model organism to test
different scenarios from those of associated wet species. By means of mitochondrial
COI analyses of 96 specimens we compared the genetic divergence between
populations that comprise the whole known range of this ant. Our results show some
shallow phylogeographical structure along the populations analyzed with an isolation
by distance effect. However, the data do not allow recognizing old or recent
phylogeographic barriers with an abrupt change of genotypes. Open shrubland,
grasslands and sandy environments are the dominant coastal environments in
southern Brazil and our results suggest that M. simplex was not affected during the
LGM and does not show any split distribution.
����68 Safaa Dalla
How insects achieve resistance to dietary toxins: in vitro tests of amino acid
substitutions in their Na,K-ATPase
Authors: Safaa Dalla 1 , Susanne Dobler 1
Affiliations: 1 Biozentrum Grindel - Molekulare Evolutionsbiologie, Universität
Hamburg
The Na, K-ATPase is a ubiquitous protein which catalyses 1 molecule of ATP to
exchange 3 Na+ ions for 2 K+ ions across the cell membrane. This important
transmembrane carrier is specifically inhibited by cardenolides (cardiac glycosides)
such as ouabain that bind to a well described binding pocket on the extracellular side
of the enzyme. Nevertheless, some insect species that feed on cardenolidecontaining
plants have a high tolerance to cardenolides. Genetic analysis of the Na,K-
ATPase revealed that amino acid substitutions in the cardenolide binding pocket may
play a role in making the enzyme insensitive to cardenolides. We genetically
engineered the D. melanogaster Na,K-ATPase ? subunit to incorporate amino acid
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