Making the best of a bad situation: host partial resistance and bypass of behavioral manipulation by parasites?

• Parasitic manipulation dramatically reduces host fitness.
• Evolution of partial resistance and bypass of manipulation are options for parasitized hosts.
• Partial resistance can postpone death and allow additional reproductive episodes.
• Novel host traits can alleviate the detrimental fitness consequences of manipulation.

With few exceptions, parasitic manipulation dramatically reduces host fitness. That said, evidence of host resistance to behavior-manipulating parasites is scarce. Here, we suggest that the evolution of partial resistance, as well as bypass, to manipulation (PRM and BPM, respectively) represents new, seldom-explored options for parasitized hosts. Natural selection could favor hosts that partially resist certain manipulative dimensions to postpone their death and perform additional reproductive episodes (PRM). Alternatively, manipulated hosts may express novel traits that do not alter the manipulation per se but that alleviate its detrimental fitness consequences (BPM). If effective, PRM and BPM have many implications for the ecology and evolution of hosts and their parasites, especially the evolution of multidimensional manipulations.