Increased responsiveness in feeding behaviour of Caenorhabditis elegans after experimental coevolution with its microparasite Bacillus thuringiensis.

Immune responses, either constitutive or induced, are costly. An alternative defence strategy may be based on behavioural responses. For example, avoidance behaviour reduces contact with pathogens and thus the risk of infection as well as the requirement of immune system activation.

Host-parasite local adaptation after experimental coevolution of Caenorhabditis elegans and its microparasite Bacillus thuringiensis.

Coevolving hosts and parasites can adapt to their local antagonist. In studies on natural populations, the observation of local adaptation patterns is thus often taken as indirect evidence for coevolution. Based on this approach, coevolution was previously inferred from an overall pattern of either parasite or host local adaptation.

Multiple reciprocal adaptations and rapid genetic change upon experimental coevolution of an animal host and its microbial parasite.

The coevolution between hosts and parasites is predicted to have complex evolutionary consequences for both antagonists, often within short time periods. To date, conclusive experimental support for the predictions is available mainly for microbial host systems, but for only a few multicellular host taxa. We here introduce a model system of experimental coevolution that consists of the multicellular nematode host Caenorhabditis elegans and the microbial parasite Bacillus thuringiensis.