flwr_traits_2019.csv

Dataset created to compare floral morphometric traits and flower nectar quantity and quality of three Cucurbita sister species. Staminate and pistiallate flowers were collected in the states of Jalisco, Guerrero and Michoacan in Mexico. To determine whether floral attributes differ between cucurbit species, we compared the size of each floral trait using a generalized linear mixed model (lme4 function ‘glmer’, Bates 2010, and stats function ‘glm’, R Core Team 2020) followed by a post hoc Tukey test (emmeans function ‘emmeans’, Lenth 2021). Floral trait measurements were log10 transformed to obtain normality. Pollinator attraction traits corolla (CD, TL, CL, TD1, TD2, TD3; Fig. 1A and B) were evaluated individually as response variables and the interaction between cucurbit species and floral sex as fixed factor. Plant reproductive traits, androecium (AD, StL, AL; Fig. 1C), gynoecium (SD, SL, PL, OL, OD; Fig. 1D) and nectary diameter (NDm and NDf; Fig. 1C and D), were evaluated individually as the response variables and the cucurbit species as the predictor variable. Field sites were set as a random variable to account for site level variation. Because multiple flowers were measured from the same plant, plant ID was nested within the site random variable to account for individual level variation within each plant at each site. Significance level was found using type III Wald chi-square tests (car function ‘Anova’, Fox and Weisberg 2019). Additionally, to analyze the individual variation of each floral trait, we calculated the coefficient of variation (CV = s / x̅) for one randomly selected flower from each plant. All floral attribute analysis were completed in the R program (version 4.0.1) (R Core Team, 2020). To analyze whether volume and sugar concentration of nectar differs between cucurbits species, floral sex, and time, we performed generalized linear mixed models (nectar volume: lme4 function ‘glmer’, Bates 2010, nectar sugar concentration: glmmTMG function ‘glmmTMB’, Magnusson et al. 2018) followed by a post hoc Tukey test (emmeans function ‘emmeans’, Lenth 2021). To normalize data, we converted nectar volumes using log10 and sugar concentrations were converted to proportion. We used nectar volume and sugar concentration as response variables and the interaction between cucurbit species, flower sex and time as predictive variables (emmeans function ‘emmeans’, Lenth 2021). Time was transformed to decimal time (time x 1440) for analysis. Because some pistillate and staminate flowers were sampled from the same plant, Plant ID was used as a random variable which was nested within the field site to control for site level variation. For nectar volume, we used a normal distribution and for sugar concentration we used a beta distribution