title: Evolution: Parasite Pressure Favors Fortress-like Defence.
abstract: Why are some defence mechanisms expressed constitutively, while others are induced only upon exposure? Experimental evolution in a bacteria-phage system provides empirical support for the prediction that high frequency of exposure to parasites selects for constitutive defence despite associated costs.
authors.affiliation: Department of Ecology & Evolutionary Biology, Princeton University, Princeton, NJ 08544, USA. Electronic address: algraham@princeton.edu.
authors.forename: Andrea L
authors.initials: AL
authors.lastname: Graham
mesh_terms: D000818:Animals; D001419:Bacteria / Q000821:virology*; D001435:Bacteriophages / Q000235:genetics*; D064113:CRISPR-Cas Systems / Q000235:genetics*; D064112:Clustered Regularly Interspaced Short Palindromic Repeats / Q000235:genetics*; D019143:Evolution, Molecular; D016678:Genome