Final published version
Research output: Contribution to Journal/Magazine › Journal article › peer-review
Research output: Contribution to Journal/Magazine › Journal article › peer-review
}
TY - JOUR
T1 - Rapid evolution rescues hosts from competition and disease but—despite a dilution effect—increases the density of infected hosts
AU - Strauss, Alexander T.
AU - Hite, Jessica L.
AU - Shocket, Marta S.
AU - Cáceres, Carla E.
AU - Duffy, Meghan A.
AU - Hall, Spencer R.
PY - 2017/12/6
Y1 - 2017/12/6
N2 - Virulent parasites can depress the densities of their hosts. Taxa that reduce disease via dilution effects might alleviate this burden. However, ‘diluter’ taxacan also depress host densities through competition for shared resources.The combination of disease and interspecific competition could even drivehosts extinct. Then again, genetically variable host populations can evolve inresponse to both competitors and parasites. Can rapid evolution rescue hostdensity from the harm caused by these ecological enemies? How might suchevolution influence dilution effects or the size of epidemics? In a mesocosmexperiment with planktonic hosts, we illustrate the joint harm of competitionand disease: hosts with constrained evolutionary ability (limited phenotypicvariation) suffered greatly from both. However, populations starting withbroader phenotypic variation evolved stronger competitive ability duringepidemics. In turn, enhanced competitive ability—driven especially by parasites—rescued host densities from the negative impacts of competition,disease, and especially their combination. Interspecific competitors reduceddisease (supporting dilution effects) even when hosts rapidly evolved.However, this evolutionary response also elicited a potential problem. Populations that evolved enhanced competitive ability and maintained robusttotal densities also supported higher densities of infections. Thus, rapidevolution rescued host densities but also unleashed larger epidemics.
AB - Virulent parasites can depress the densities of their hosts. Taxa that reduce disease via dilution effects might alleviate this burden. However, ‘diluter’ taxacan also depress host densities through competition for shared resources.The combination of disease and interspecific competition could even drivehosts extinct. Then again, genetically variable host populations can evolve inresponse to both competitors and parasites. Can rapid evolution rescue hostdensity from the harm caused by these ecological enemies? How might suchevolution influence dilution effects or the size of epidemics? In a mesocosmexperiment with planktonic hosts, we illustrate the joint harm of competitionand disease: hosts with constrained evolutionary ability (limited phenotypicvariation) suffered greatly from both. However, populations starting withbroader phenotypic variation evolved stronger competitive ability duringepidemics. In turn, enhanced competitive ability—driven especially by parasites—rescued host densities from the negative impacts of competition,disease, and especially their combination. Interspecific competitors reduceddisease (supporting dilution effects) even when hosts rapidly evolved.However, this evolutionary response also elicited a potential problem. Populations that evolved enhanced competitive ability and maintained robusttotal densities also supported higher densities of infections. Thus, rapidevolution rescued host densities but also unleashed larger epidemics.
U2 - 10.1098/rspb.2017.1970
DO - 10.1098/rspb.2017.1970
M3 - Journal article
VL - 284
JO - Proceedings of the Royal Society B: Biological Sciences
JF - Proceedings of the Royal Society B: Biological Sciences
SN - 0962-8452
IS - 1868
ER -