|Fakultät für Biologie und Vorklinische Medizin|
|Institut für Zoologie|
|Lehrstuhl für Zoologie / Evolutionsbiologie|
|Dr. Alexandra Schrempf|
Research interests: Sexual selection, aging and reproduction in social insects
Study system: mainly Cardiocondyla ants
Cardiocondyla is characterized by a male polymorphism with winged disperser males and wingless fighter males (“ergatoid males”), which engage in fatal fighting over access to the virgin queens eclosing in their natal nest. Sexuals mate in the lab within the nests, and the life span of queens is comparatively short, so that the total lifetime reproductive success of queens can be determined.
Some of the current projects are
Spermatogenesis and germ line stem cell degeneration in social Hymenoptera.
Testes usually degenerate in social Hymenoptera males early during adulthood. In wingless males of the ant genus Cardiocondyla, spermatogenesis is ongoing as an adaptation to intranidal mating and a long life. In this project, we investigate germ line stem cell degeneration in winged males in comparison to wingless males (see Nathalie Moske)
Parental age effects
Testes degeneration in winged males and ongoing spermatogenesis in wingless males allows us to vary not only the parental age, but also the „sperm“ age and investigate the effects on offspring fitness and also on the mating partner, as we know that mating can have profound effects on females depending on the male they mate with.
Trade of sexuals among colonies in an ant with local mating
In the monogynous species Cardiocondyla elegans, female sexuals are exchanged between different nests. Interestingly, the females do not walk on their own but are actively transported / carried by the workers (Lenoir et al. 2007). In this project we investigate this trading in detail, e.g. whether sexuals are traded only among related colonies and whether colony odour plays a role in acceptance of alien individuals.
Supported by the DAAD (Procope), cooperation with Jean-Luc Mercier and Christophe Lucas, Univ. Tours
Aging and fecundity in Cardiocondyla ants
This project is part of a research unit (Sociality and the reversal of the
fecundity/longevity trade-off) and is conducted together with Jan Oettler
Heritability of sexual traits (vs. environment)
Life-history trade-offs in ant males
Maintenance and reproduction in ant colonies
Mating and immunity
Interested students are always welcome for practical, bachelor – and master thesis.