• Energy Research

Changing sex ratios Climate-warming temperatures might be expected to affect the sex ratio of species if sex determination is temperature-dependent. Petry et al. show that indirect climate effects could also alter sex ratios in species in which sex is genetically determined and damage reproductive fitness (see the Perspective by Etterson and Mazer). Over four decades, sex ratios in populations of a dioecious alpine plant have shifted toward females as a result of the different water needs of the male and female plants. The lack of males has reduced the reproductive success and fitness of the females. Similar subtle differences between sexes in environmental sensitivities could eventually lead to population declines. Science , this issue p. 69 ; see also p. 32

Annual rates of sex- and size-specific growth and survival from tagged plants at four populations (1978-1981). See README.txt for column descriptions.

AbstractOrganisms use environmental cues to align their phenology—the timing of life events—with sets of abiotic and biotic conditions that favor the successful completion of their life cycle. Climate change has altered the environmental cues organisms use to track climate, leading to shifts in phenology with the potential to affect a variety of ecological processes. Understanding the drivers of phenological shifts is critical to predicting future responses, but disentangling the effects of temperature from precipitation on phenology is often challenging because they tend to covary. We addressed this knowledge gap in a high‐elevation environment where phenological shifts are associated with both the timing of spring snow melt and temperature. We factorially crossed early snow melt and passive warming treatments to (1) disentangle the effects of snow melt timing and warming on the phenology of flowering and fruiting and reproductive success in three subalpine plant species (Delphinium nuttallianum, Valeriana edulis, and Potentilla pulcherrima); and (2) assess whether snow melt acts via temperature accumulation or some other aspect of the environment (e.g., soil moisture) to affect phenological events. Both the timing and duration of flowering and fruiting responded to the climate treatments, but the effect of snow melt timing and warming varied among species and phenological stages. The combined effects of the treatments on phenology were always additive, and the snow melt treatment often affected phenology even when the warming treatment did not. Despite marked responses of phenology to climate manipulations, the species showed little change in reproductive success, with only one species producing fewer seeds in response to warming (Delphinium, −56%). We also found that snow melt timing can act both through temperature accumulation and as a distinct cue for phenology, and these effects are not mutually exclusive. Our results show that one environmental cue, here snow melt timing, may act through multiple mechanisms to shift phenology.

Pollen analogue (fluorescent dye) transfer by Valeriana edulis pollinators from dyed males to surrounding females. See README.txt for column descriptions.

This .zip archive contains a shapefile (including .shp, .shx, .dbf, and .prj components) that describes the boundary of a representative plot of Valeriana edulis plants growing at Emerald Lake.

Estimation of the mating function – how local operational sex ratio affects female reproductive success – of Valeriana edulis. This script includes a simulation of pollen limitation across a range of operational sex ratios.

Carbon isotope ratios of Valeriana edulis leaf samples used to test for sex differences in integrated water use efficiency. See README.txt for column descriptions.

AbstractGenetic differentiation and phenotypic plasticity jointly shape intraspecific trait variation, but their roles differ among traits. In short‐lived plants, reproductive traits may be more genetically determined due to their impact on fitness, whereas vegetative traits may show higher plasticity to buffer short‐term perturbations. Combining a multi‐treatment greenhouse experiment with observational field data throughout the range of a widespread short‐lived herb,Plantago lanceolata, we (1) disentangled genetic and plastic responses of functional traits to a set of environmental drivers and (2) assessed how genetic differentiation and plasticity shape observational trait–environment relationships. Reproductive traits showed distinct genetic differentiation that largely determined observational patterns, but only when correcting traits for differences in biomass. Vegetative traits showed higher plasticity and opposite genetic and plastic responses, masking the genetic component underlying field‐observed trait variation. Our study suggests that genetic differentiation may be inferred from observational data only for the traits most closely related to fitness.