2. Behavioral Biology TALKS - Deutsche Zoologische Gesellschaft

Population modeling has been used as a powerful tool to extrapolate measured
effects on individuals to the population level. It allows including the variability
between individuals in response to chemical‘s exposure and accounting for the
different mechanisms of action of a toxicant.
In this work, we use an already developed and validated individual-based model for
D. magna (IDamP, see Preuss et al, 2009) as a virtual laboratory in order to
investigate the sub-lethal effects of a hypothetical toxicant on the population level,
and to compare their relative magnitudes of effects.
Different simulation scenarios will be tested: Effects on reproductive performance
might be exerted via various mechanisms like reduction in the filtration rate, delay in
the time to first reproduction, etc. A slowed or inhibited growth induced by exposure
to the toxicants will also be assessed solely or combined to reproductive effects.
Modeling these different responses will be addressed in combination to varying
environmental factors like variable food levels.
Using such an approach allows us to explain the interactions between natural factors
and toxicity at the level of individuals which ultimately emerge as effects on
populations‘ properties.
20. Symposium “Genomics of adaptation and
population genomics”
Sunday, September 23, 2012
Key Note: Chair: Axel Meyer R 513 / 11:00
Scott Edwards
The phylogeography-phylogenetics continuum in the genomic era
Author: Scott V. Edwards 1
Affiliation: 1 Department of Organismic and Evolutionary Biology and Museum
of Comparative Zoology, Harvard University, Cambridge, USA
As genomics makes available ever-increasing numbers of loci for phylogenetic
analysis, the diversity of gene histories due to incomplete lineage sorting and other
factors increases as well. Concatenation of multilocus data sets into supermatrices
has proven an effective way of increasing phylogenetic signal for the Tree of Life.
However, when analyzed by standard methods that ignore gene tree heterogeneity,
theory suggests that concatenation yields inconsistent estimates of phylogenetic
relationships when gene tree heterogeneity is high. Natural selection is yet another
variable that can increase or decrease the degree of gene tree heterogeneity. Here I
illustrate these principles with empirical examples from songbird genomes and
transcriptomes, and from eutherian mammals. Gene trees from transcripts in the
gonads of the promiscuous Australian Fairy Wrens (Maluridae) show less evidence of
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