SPP 1399 - Work package: Coevulution between Tribolium castaneum and Bacillus thuringiensis: On the evolutionary significance of genetic specificity and specific immunity.

Basic data for this project

Description

Host-parasite coevolution critically relies on genetic specificity, which will facilitate reciprocal genetic change in interacting hosts and parasites. On the other hand, specificity can also come in a phenotypically plastic form, when induced immune responses show specificity for a certain parasite type. We may expect that a preponderance of such phenotypic flexibility reduces the speed with which hosts and parasites change genetically, which means that it might slow down Red Queen dynamics. This proposal addresses both forms of specificity and their relevance for host-parasite coevolution. We particularly address the question how such specificity evolves. Experimental host-parasite coevolution between the red flour beetle Tribolium castaneum and its microparasite Bacillus thuringiensis will serve to test whether coevolution creates genetic specificity. On the other hand, we will use experimental evolution to test whether the immune system can evolve towards higher or lower capacity to respond with induced, specific responses. Combining these approaches, we will finally study the degree to which induced immunity influences the speed of host-parasite coevolution. Importantly, this priority programme will enable us to directly study the genetic causes of both specific immunity and the genetic changes during host-parasite coevolution.