Animal behaviour, marine biosphere, fish diversity and different aquaticecosystems have been major interests of mine for many years.

In my Master thesis I investigated the influence of body condition on the solution of sexual conflict about parental investment in the biparental cichlid Eretmodus cyanostictus. In a lab experiment I tested how parental investment and the performance of female display behaviour changed in connection with different food treatments. E. cyanostictus males took over the young later and incubated the clutch for shorter periods under limited food conditions. At the same time, no effect of food limitation on the length of female incubation period was detected, apart from that they signalled their readiness to shift more intensely. My results suggested that males adjust their incubation share to their own body condition, but do not respond to their mate's condition and increased levels of female display behaviour.

In my Ph.D thesis I investigate the function, mechanisms and ontogeny of collaborative hunting in the yellow saddle goatfish (Parupeneus cyclostomus).

Yellow saddle goatfish are the first fish species described as collaborative hunters where individuals play different roles during a hunt ('chasers' and 'blockers'), and they encircle prey hiding in coral crevices and try to pry it out by inserting their barbels. I have designed an experimental setup where the goatfish will be confronted with mobile invertebrate prey hiding in a tunnel system. Cameras that are installed above and below will allow me to conduct detailed behavioural analyses

1) to test the relationship between group size and hunting success,
2) to find out whether the cooperation is a by-product of self-regarding behaviour or proper reciprocity based on mutual investments.

The laboratory experiments will be complemented with field observations on yellow goatfish of all size classes. I will describe their foraging techniques in detail in order to document any changes in the complexity of coordination with other individuals during the ontogeny. I consider it likely to find significant changes as yellow goatfish change their diet during ontogeny, switching from invertebrate prey to fishes.