Species' responses to climate change depend on the interplay of migration and adaptation, yet we know relatively little about the potential for adaptation. Genetic adaptations to climate change often involve shifts in the timing of phenological events such as flowering. If populations at the edge of a species' range have lower genetic variation in phenological traits than central populations, then their persistence under climate change could be threatened. To test this hypothesis, we performed artificial selection experiments using the scarlet monkeyflower (Mimulus cardinalis) and compared genetic variation in flowering time among populations at the latitudinal center, northern edge, and southern edge of the species' range. We also assessed whether selection on flowering time yielded correlated responses in functional traits, potentially representing a cost associated with early or late flowering. Contrary to prediction, southern populations exhibited greater responses to selection on flowering time than central or northern populations. Further, selection for early flowering resulted in correlated increases in specific leaf area and leaf nitrogen, whereas selection for late flowering led to decreases in these traits. These results provide critical insights about how spatial variation in the potential for adaptation may affect population persistence under changing climates.
Mimulus cardinalis data from artificial selection experiment
This data file includes flowering time, specific leaf area, leaf nitrogen content, relative growth rate, and carbon isotope ratio for each Mimulus cardinalis individual in experiment (see publication for further details).
Column names are as follows:
Generation: year in which artificial selection was performed; parental generation (2012); 1 generation of selection (2013); 2 generations of selection (2014)
Region: range position from which populations originate; northern edge (N), latitudinal range centre (C), or southern edge (S)
Population: location from which individuals were collected (see Fig. 1 and Table 1 in publication)
Line: artificial selection line; early flowering (early); unselected (control); late flowering (late)
Population.Line: selection line nested within population
Par1: identity of parent 1 of each individual in 2013 and 2014 generations; used in calculations of weighted selection differentials
Par2: identity of parent 2 of each individual in 2013 and 2014 generations; used in calculations of weighted selection differentials
Family: full-sibling seed family
Replicate: replicates of each full-sibling seed family; only relevant in 2013 and 2014 generations
Family.Replicate: replicate nested within full-sibling seed family; only relevant in 2013 and 2014 generations
FloweringTime: number of days from germination to first flower
SLA: specific leaf area (mm2/mg); only measured in 2014 generation
percent.N: percent leaf nitrogen content; only measured in 2014 generation on a subset of individuals
RGR: relative growth rate in early seedling stem length (cm cm-1 day-1); only measured in 2014 generation
delta.13C: carbon isotope ratio (δ13C); only measured in 2014 generation on a subset of individuals
Mimulus.cardinalis.2012-2014.csv
Mimulus cardinalis selected and unselected lines from artificial selection experiment
This data file includes unique IDs for the Mimulus cardinalis individuals selected for early flowering, late flowering, and unselected control lines in the 2012 and 2013 generations.
Column names are as follows:
Generation: year in which artificial selection was performed; parental generation (2012); 1 generation of selection (2013); 2 generations of selection (2014)
Region: range position from which populations originate; northern edge (N), latitudinal range centre (C), or southern edge (S)
Population: location from which individuals were collected (see Fig. 1 and Table 1 in publication)
Line: artificial selection line; early flowering (early); unselected (control); late flowering (late)
Population.Line: selection line nested within population
ID: full-sibling seed family (in the case of data from the 2012 generation) or replicate nested within full-sibling seed family (in the case of data from the 2013 generation)
FloweringTime: number of days from germination to first flower
Mimulus.cardinalis.SelectionLines.2012-2013.csv
Mimulus cardinalis data from artificial selection experiment based on a subset of C1 individuals
This data file includes flowering time, measured as number of days from germination to first flower, for each Mimulus cardinalis individual in artificial selection experiment based on a subset of individuals from the C1 population (see publication for further details).
Column names are as follows:
Generation: year in which artificial selection was performed; parental generation (2012); 1 generation of selection (2013); 2 generations of selection (2014)
Line: artificial selection line; early flowering (early); unselected (control); late flowering (late)
Family: full-sibling seed family
Replicate: replicates of each full-sibling seed family; only relevant in 2013 and 2014 generations
Family.Replicate: replicate nested within full-sibling seed family; only relevant in 2013 and 2014 generations
FloweringTime: number of days from germination to first flower
Subsampled.Mimulus.cardinalis.2012-2014.csv
Mimulus cardinalis selected and unselected lines from artificial selection experiment based on a subset of C1 individuals
This data file includes unique IDs for the Mimulus cardinalis individuals selected for early flowering, late flowering, and unselected control lines in the 2012 and 2013 generations. Data are derived from artificial selection experiment based on a subset of individuals from the C1 population (see publication for further details).
Column names are as follows:
Generation: year in which artificial selection was performed; parental generation (2012); 1 generation of selection (2013); 2 generations of selection (2014)
Line: artificial selection line; early flowering (early); unselected (control); late flowering (late)
ID: full-sibling seed family (in the case of data from the 2012 generation) or replicate nested within full-sibling seed family (in the case of data from the 2013 generation)
FloweringTime: number of days from germination to first flower
Subsampled.Mimulus.cardinalis.SelectionLines.2012-2013.csv