title: Evolutionary rescue from extinction is contingent on a lower rate of environmental change.
abstract: The extinction rate of populations is predicted to rise under increasing rates of environmental change. If a population experiencing increasingly stressful conditions lacks appropriate phenotypic plasticity or access to more suitable habitats, then genetic change may be the only way to avoid extinction. Evolutionary rescue from extinction occurs when natural selection enriches a population for more stress-tolerant genetic variants. Some experimental studies have shown that lower rates of environmental change lead to more adapted populations or fewer extinctions. However, there has been little focus on the genetic changes that underlie evolutionary rescue. Here we demonstrate that some evolutionary trajectories are contingent on a lower rate of environmental change. We allowed hundreds of populations of Escherichia coli to evolve under variable rates of increase in concentration of the antibiotic rifampicin. We then genetically engineered all combinations of mutations from isolates evolved under lower rates of environmental change. By assessing fitness of these engineered strains across a range of drug concentrations, we show that certain genotypes are evolutionarily inaccessible under rapid environmental change. Rapidly deteriorating environments not only limit mutational opportunities by lowering population size, but they can also eliminate sets of mutations as evolutionary options. As anthropogenic activities are leading to environmental change at unprecedented rapidity, it is critical to understand how the rate of environmental change affects both demographic and genetic underpinnings of evolutionary rescue.
authors: Department of Biology and BEACON Center for the Study of Evolution in Action, University of Washington, Seattle, Washington 98195, USA.
authors: Haley A
authors: HA
authors: Lindsey
authors: Jenna
authors: J
authors: Gallie
authors: Susan
authors: S
authors: Taylor
authors: Benjamin
authors: B
authors: Kerr
mesh_terms: D000222:Adaptation, Physiological / Q000187:drug effects / Q000235:genetics*; D000904:Antibiotics, Antitubercular / Q000494:pharmacology; D005075:Biological Evolution; D057231:Climate Change / Q000401:mortality / Q000706:statistics & numerical data; D015169:Colony Count, Microbial; D004252:DNA Mutational Analysis; D012321:DNA-Directed RNA Polymerases; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000166:cytology / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D029968:Escherichia coli Proteins / Q000235:genetics; D053476:Extinction, Biological; D005798:Genes, Bacterial / Q000235:genetics; D056084:Genetic Fitness / Q000187:drug effects / Q000235:genetics*; D005838:Genotype; D006802:Human Activities; D008826:Microbial Sensitivity Tests; D008954:Models, Biological; D016296:Mutagenesis / Q000187:drug effects / Q000235:genetics*; D009154:Mutation / Q000235:genetics; D011156:Population Density; D012293:Rifampin / Q000494:pharmacology; D013997:Time Factors
chemical_list: D000904:Antibiotics, Antitubercular; D029968:Escherichia coli Proteins; C540081:rpoB protein, E coli; D012321:DNA-Directed RNA Polymerases; D012293:Rifampin
references: Biol Lett. 2013 Feb 23;9(1):20120396
references: 22809724
references: Proc Natl Acad Sci U S A. 1979 Oct;76(10):5269-73
references: 291943
references: Theor Popul Biol. 1983 Apr;23(2):202-15
references: 6612632
references: Nat Genet. 2004 Apr;36(4):423-6
references: 15072075
references: PLoS Genet. 2009 Jul;5(7):e1000578
references: 19629166
references: PLoS Genet. 2011 Apr;7(4):e1002056
references: 21552329
references: J Evol Biol. 2008 Nov;21(6):1724-31
references: 18681913
references: Evolution. 2011 Aug;65(8):2370-9
references: 21790582
references: Evolution. 2009 Nov;63(11):2952-65
references: 19619223
references: Ecol Lett. 2012 Apr;15(4):365-377
references: 22257223
references: PLoS Med. 2009 Feb 10;6(2):e2
references: 19209951
references: Genetics. 2010 Dec;186(4):1345-54
references: 20876562
references: J Bacteriol. 1997 Oct;179(20):6228-37
references: 9335267
references: Science. 2006 Jun 30;312(5782):1944-6
references: 16809538
references: Genetics. 2000 Dec;156(4):1471-81
references: 11102350
references: Evolution. 2005 Jun;59(6):1165-74
references: 16050094
references: Evolution. 2011 Sep;65(9):2541-52
references: 21884055
references: Nat Genet. 2011 Dec 18;44(1):106-10
references: 22179134
references: Heredity (Edinb). 2012 Aug;109(2):71-7
references: 22491062
references: Science. 2006 Apr 7;312(5770):111-4
references: 16601193
references: Science. 2011 Jun 10;332(6035):1327-30
references: 21659606
references: Environ Pollut. 2009 Nov;157(11):2893-902
references: 19560847
references: Nature. 2005 Feb 10;433(7026):621-4
references: 15703744
references: PLoS Pathog. 2011 Jul;7(7):e1002158
references: 21811410
references: Evol Appl. 2008 Feb;1(1):3-16
references: 25567487
references: Conserv Biol. 2007 Oct;21(5):1353-5
references: 17883501
references: Ecol Lett. 2009 Sep;12(9):942-8
references: 19659574