At Animal Ecology I until 12/2014
Daphnia in life support systems for space exploration
Christian Laforsch and Kathrin Schoppmann, funded by DLR/BMWi
Daphnia is a key model system in ecology, evolution, and environmental sciences. The recently sequenced genome not only opens the door for environmental genomics, further, it is the stepping stone to introduce Daphnia as a model organism in the entire field of life science research. In addition, its essential role in aquatic food webs renders Daphnia to be a player in future life support systems for space exploration. Its short reproduction time and large offspring quantity lead to rapid biomass production, which can feed higher trophic levels, such as higher crustaceans or fish. This could provide an important protein source for prospective on long-term missions. Furthermore, the use of dormant eggs offers great advantages for cheep upload and robustness against fluctuations in this artificial environment. Hence, we are developing a semicontinuous life support system, with Daphnia as a key player. However, little is known about the impact of gravity on the behaviour and physiology of this organism. Two questions shall be answered within this project. How does the graviperceptive mechanism of daphnids work? And secondly, is Daphnia suitable for artificial, modular food webs? For microgravity research, we perform experiments in free fall conditions, which can be experienced during parabolic flights and at the drop tower. Here, only fast effects on behaviour or physiological pathways (at the molecular level) can be monitored. The findings are supplemented by experiments in orbit, lasting several minutes. Long-term studies on life history parameters are performed in simulated weightlessness on fast rotating 2D clinostats in cooperation with DLR, Cologne.