Ecological divergence is a main source of trait divergence between closely related species. Despite its importance in generating phenotypic diversity, the genetic architecture of most ecologically relevant traits is poorly understood. Differences in elevation can impose substantial selection for phenotypic divergence of both complex, correlated suites of traits (such as life history), as well as novel adaptations. Here, we use the Mimulus guttatus species complex to assess if divergence in elevation is accompanied by trait divergence in a group of closely related perennial species, and determine the genetic architecture of this divergence. We find that divergence in elevation is associated with differences in multivariate quantitative life history traits, as well as a unique trait; the production of rhizomes, which may play an important role in overwintering survival. However, the extent of phenotypic divergence among species depended on ontogeny, suggesting that species also diverged in investment strategies across development. Lastly, we show that the genetic architecture of life history divergence between two species is simple, involving few mid to large effect Quantitative Trait Loci (QTLs), and that the genetic architecture of the ability to produce rhizomes changes through development, which has potential implications for hybrid fitness in the wild.

Occurrence+PredictedOccurrence Dataset: Maxent models were run for 5 perennial taxa of the M. guttatus species complex based on herbarium records from GBIF. Models were run using 4 bioclim variables (temperature and precipitation seasonality, mean temperature of the warmest quarter, and mean precipitation of the warmest quarter) plus elevation downloaded to 2.5 arc degrees. This dataset represents a subset of 500 suitable locales for each taxa from the predicted ranges concatenated with true herbarium records, plus affiliated ecological data from those locales (all climate variables from WorldClim, plus elevation, plus the PCs from a PCA of these variables).

PopulationPhenotypicSurvey: plants of 5 perennial taxa were grown in the Duke Greenhouses under long day warm conditions (18h, 22 degrees C) and surveyed at 3 developmental stages (3 weeks post germination, day of first flower, 3 weeks post first flower) for several life history traits. Phenotypic data for each developmental stage, plus information regarding the geographic locale of origin for each population

RqtlFormatedGenotype+Phenotype: Genotype and phenotype information for 213 F2 individuals across 1,311 markers inferred from a modified Andolfatto shotgun sequencing approach using the Csp6I enzyme.

Hybrids+pars_PhenotypesAcrossDev: phenotypes for all F1s, F2s, and inbred line replicates across three developmental stages.