My research synthesizes the fields of cellular aging and sexual selection in order to shed light on the role of sperm age in sperm competition and use. Sperm age, long recognized in the fields of human medicine and animal breeding as an important factor in determining fertilization success and offspring viability, has been largely overlooked by evolutionary biologists. Given that much of the observed across-male variation in fertilization success remains unexplained by commonly-studied sperm and ejaculate traits like sperm number, motility, and morphology, sperm age is a likely candidate for predicting sperm function.
Sperm aging and sperm use patterns in Drosophila
Recent work shows that some female insects delay the aging of stored sperm cells by reducing the cells’ metabolic rates, thereby limiting their production of damaging reactive oxygen species. This mechanism may underlie the complex spatial and temporal patterns of sperm storage and use in the model system Drosophila. Drosophila females have two types of sperm storage organs: the seminal receptacle (SR) and the spermathecae (ST). In D. melanogaster, the SR is used for short-term and the ST for long-term storage. In the closely related D. simulans, the two organ types have opposing fertilization biases: the SR favors the first male to mate, while the ST favor the second male. Sister species D. mauritiana, meanwhile, shows no temporal or mating-order biases in sperm use. Our project investigates how differential modulation of sperm metabolism in female storage, across the two organ types and the three species, relates to these different usage patterns. We are also investigating potential mechanisms of delayed sperm aging in storage, including oxygen restriction and high ion concentration.
22 Sept 2015 Klaus reads from his book at the Berlin Natural History Museum
Welcome to Cornelia who joins us a technician.
Bernard was awarded a collaborative DFG grant on cuticle development. Excellent! Many congratulations, Bernard!
12 Juni 2015: Congratulations to Bernard for being appointed Guest Professor at the University of Shaanxi.
Arthropods can break down chitin (nobody else can) – do you want to know how? We are looking for somebody who characterises chitinases in insects. More details here (in German).
Bedbug females express a protein in their skin that is self-sealing after wounding. We are interested in how this is anchored in the tissue. If you are interested in addressing this novel topic, please get in touch. More details here (in German).
6 July 2015. Welcome Renata!
3 July. Klaus will present a performative reading at the Lange Nacht der Wissenschaften in Dresden. 21:00 Biology Building, Zellescher Weg 20b, Room E33.
Applying evolutionary theory to medicine: A discussion on mitochondrial replacement therapy is out in Geburtshilfe und Frauenheilkunde. Can be inspected here, but is subject to copyright.
Klaus gives a seminar on “Sexual conflict in the bedbug” at the Freie Univ Berlin
Klaus presents bedbugs and interesting facts about them during the Lange Nacht der Wissenschaften in Berlin, 13 June 21:00.
5 June 2015: Klaus accepted as a member of staff in the Dresden International PhD Programme DIPP. See his webpage at DIPP.
We are looking for somebody who helps in a project on the cultural history of bedbugs. See here for details and here (scroll to ‘Insects and Man’.)
Welcome to Conni, Christin, and Bernard who joined the lab today, or will in a week.
A milestone paper in Developmental Cell on the function of the triple-repeat protein Anaconda organising tricellular junctions in Drosophila melanogaster. In collaboration with the Uv (Göteborg, Sweden) and Luschnig (Münster, Germany) labs. Online now: doi: 10.1016/j.devcel.2015.03.023. Many congratulations, Bernard!
Barbara Eckel and Guo Ruijian will join us as PhD students in November and October 2015. Barbara will be working on the Evolution of Sperm Metabolism. Ruijian won a Chinese Government Scholarship. Many congratulations! He will work on the Ecology, Genetics and Molecular Biology of Sperm Storage in Drosophila melanogaster. We are looking forward to meet you, Barbara and Ruijian!
Becky Rosengaus will give a seminar “Symbiont-mediated social immunity”on 7 May. On her trip to Europe, she visits only Vienna and our lab in Dresden. See her website for her research – come by and meet her on 6 and 7 May.
Dr Conni Wetzker agreed to join the lab, to work on sperm metabolism and meiosis in Drosophila. Hopefully from 1 June. Welcome Conni!
Dr Anne-Cecile Ribou and Prof. Dr Christoph Grunau from the University of Perpignan arrive to spend sabbatical time in our group. Welcome Ance & Christoph! It will be cold, though. Christoph will be giving a seminar Disentangling genetic and epigentic components of heritable phenotypic variation in the coevolution of hosts and parasites on 21 April (Abstract). He will also give a lecture “Epigenetics and Evolution”. Ance’s talk will be Using next-generation fluorescence probes to detect free radicals in living cells: the case of the mitochondria. Come by and meet them.
“An Ecology of Sperm” by Klaus, Ralph & Jessica is accepted by Annual Reviews of Ecology, Evolution and Systematics.
Klaus gives a talk at the Behavioural Ecology Seminar Series, University of Bern on “Sperm ecology“.
Klaus gives a talk at the Max-Planck Inst for Colloids and Interfaces in Potsdam Golm “What does sexual conflict have to do with properties of biological materials?“
Klaus reads from his new book at the Berlin Volksbuehne BOOKS Pavillion (press release in German)
Anja, our new secretary starts. Welcome Anja!
Two technician and one postdoc positions announced
Dr Ralph Dobler accepts the position in Dresden. Welcome, Ralph! Long time no seen.
The Royal Entomological Society supports Klaus’ and Stuart Reynolds’ application for a Special Interest Group ‘Arthropod Cuticle’
Klaus’ popular science book “Literarische Wanzen” is published by (Neofelis Verlag Berlin)
Klaus starts the position in Dresden (Press release in German)