Oct 16, 2012

Biologist Mareike Wurdack wins the AllGenetics-EMPSEB Award


She is a PhD student at the Research Group on Chemical Ecology and Evolutionary Biology at the University of Freiburg.

Mareike Wurdack, a 32-year old biologist at the University of Freiburg, has won the AllGenetics-EMPSEB Award. The award has been sponsored by AllGenetics and offered to the best talk presented in the 18th European Meeting of PhD Students in Evolutionary Biology (EMPSEB 18) held in Virrat (Finland) in late September. The AllGenetics-EMPSEB Award consists of a one-week trip to the Galician county of Ortigueira, where the awardee and five more friends will enjoy the charming cottage Granxa do Souto. The cottage is located very close to some of the most amazing beaches in Spain and to other areas of particular environmental interest, such as Ortigueira Estuary or A Capelada Mountains.

Mareike is a PhD student of Dr. Thomas Schmitt at Freiburg University (Germany) where she studies the evolution of species-specific cuticular hydrocarbon (CHC) profiles in solitary Hymenoptera. CHCs are found in a waxy layer on the body surface of insects and other arthropods. They primarily serve hydroregulation, but can have several derived functions, too. Different functions lead to different resulting selective pressures and affect the cuticular hydrocarbon composition of each species in a specific way.

The EMPSEB meeting provides a platform for young PhD scholars in the field of Evolutionary Biology to present their work and meet their peers from all over Europe. It takes place in a different European city each year and is organised by current PhD students in that country. This year, the meeting was organised by University of Jyväskylä and University of Helsinki researchers Robert Hegna, Ossi Nokelainen, Philipp Lehmann, Venera Tyukmaeva, Aapo Kahilainen, Annie-Maria Örmälä, Gaia Francini, Janne Valkonen, and Veronica Chevasco. Among the invited speakers were outstanding researchers from nine different countries, such as Hanna Kokko (Australia National University) and Naomi Pierce (Harvard University).

This is the first year the AllGenetics-EMPSEB Award has been offered. This award acknowledges the best work presented by young researchers at EMPSEB and aims to introduce the winner to the emblematic nature and landscapes of Ortigueira county, in Spain, very near AllGenetics headquarters.

AllGenetics is proud to announce that the 2012 AllGenetics-EMPSEB awardee Mareike Wurdack will present her work at the University of A Coruña (Spain) later this year in one of the company's infuscience events.

 

Abstract

«Consequences of an arms race between a host and three brood parasites».

Parasites and their hosts have conflicting interests – to either successfully exploit the host or to defend against the parasite attack. This situation sets the board for an evolutionary arms race between both species. The species pair then follows a trajectory through repeated cycles of fine tuning of the parasite's attack strategies and evasive actions of the host. As a special case, brood parasites need to avoid detection by the host in order to neither be attacked while in the nest nor risk the nest to be abandoned by the host afterwards. Insect brood parasites may avoid olfactory detection by mimicking the host's cuticular hydrocarbon (CHC) profile. In this case, the arms race would lead to optimised chemical mimicry in the parasite. The host could e.g. change the CHC composition in order to escape a mimetic match.

The most straightforward parasitic associations consist of one enemy (the parasite) and one target (the host). More complex variations are possible: one parasite may use several hosts or several parasites may specialise in one single host. In this study, a solitary host (Hymenoptera: Eumenidae) and its three host-specific brood parasites (Hymenoptera: Chrysididae) serve as a model of such a multi enemy / single target system. We compare the CHC profiles and predict that a brood parasite whose intrusion is detectable by the host should develop chemical mimicry. The host in return should establish counterstrategies. Competition between parasites may fuel the perfection of mimicry or the development of completely new intrusion strategies.

We found two chemotypes of the host that differ greatly in their CHC composition. The split could allow part of a population to escape a parasite's mimicry. But two parasite species have evolved a close match of CHC composition – one for each chemotype. The third parasite produces its very own CHC bouquet – it has developed a new strategy for invading host nests and can no longer be fended off by the host.