Data from: Experimental evolution for improved post-infection survival selects for increased disease resistance in Drosophila melanogaster

Disease resistance (defined as the host capacity to limit systemic
infection intensity) and disease tolerance (defined as the host capacity
to limit infection-induced damage) are two complementary defense
strategies that help the hosts maximize their survival and fitness when
infected with pathogens and parasites. In addition to the underlying
physiological mechanisms, existing theory postulates that these two
strategies differ in terms of the conditions under which each strategy
evolves in host populations, their evolutionary dynamics, and the
ecological and epidemiological consequences of their evolution. Here we
explored if one or both of these strategies evolve when host populations
are subjected to selection for increased post-infection survival. We
experimentally evolved Drosophila melanogaster populations, selecting for
the flies that survived an infection with the entomopathogen Enterococcus
faecalis, and found that the host populations evolved increased disease
resistance in response. This was despite the physiological costs
associated with increased resistance. We did not find evidence of any
change in disease tolerance in the host populations. We have therefore
demonstrated that in an experimental evolution set-up, where insect hosts
must survive an infection with a pathogenic bacterium, the hosts evolve
improved disease resistance but not disease tolerance.