Discussion
Here we provide the most robust and comprehensive evaluation to date of factors driving population genetic differentiation in seed plants. We largely found support for our hypothesis of factors that significantly influence FST and several intriguing patterns emerge from our analyses. Overall, we found higher FST for tropical, mixed-mating, non-woody species pollinated by small insects, and lower FST for temperate, outcrossing, trees pollinated by wind. Latitudinal region was the most important predictor for FST relative to the others tested. Mating system and pollination mode had equal contributions for explaining FST. Growth form was also a key factor influencing FST, while seed dispersal mode was not important in our most inclusive model (Table 2, Fig. 1).