Tom van den Beuken


My name is Tom and I have started my PhD study in July of this year at the University of Amsterdam (UvA). My research focusses on ‘Alternative Reproductive Phenotypes’ (ARPs) in animals. Such ARPs occur in many shapes and forms in multiple animal species.

The model species I investigate is Rhizoglyphus robini, a bulb mite, of which the males can develop either of two distinctive male morphs; the so-called ‘fighter’ or ‘scrambler’ morph. R. robini fighter males are usually smaller than scrambler males and have an enlarged third pair of legs which they can use to kill other mites. Scrambler R. robini males are larger than fighter males and look more like females… at least, they do to me.

Besides differences in morphology, the fighter males also differ from the scrambler males in terms of behaviour. Fighter males typically obtain mating rights in an aggressive manner whereas scrambler males generally seek to avoid physical conflict and sneak around competitors in order to mate.

The costs and benefits of these morphs, the driving forces behind ARP determination, and the effects of ARP ratios on population dynamics are poorly understood. By combining both experimental work and theoretical modelling I aim to improve our understanding of ARPs.