Natural selection on floral volatiles and other traits can change with snowmelt timing and summer precipitation.

Climate change is disrupting floral traits that mediate mutualistic and antagonistic species interactions. Plastic responses of these traits to multiple shifting conditions may be adaptive, depending on natural selection in new environments. We manipulated snowmelt date over three seasons (3-11 d earlier) in factorial combination with growing-season precipitation (normal, halved, or doubled) to measure plastic responses of volatile emissions and other floral traits in Ipomopsis aggregata.

Pollinator and habitat-mediated selection as potential contributors to ecological speciation in two closely related species.

In ecological speciation, incipient species diverge due to natural selection that is ecologically based. In flowering plants, different pollinators could mediate that selection (pollinator-mediated divergent selection) or other features of the environment that differ between habitats of 2 species could do so (environment-mediated divergent selection). Although these mechanisms are well understood, they have received little rigorous testing, as few studies of divergent selection across sites of closely related species include both floral traits that influence pollination and vegetative traits that influence survival.

Effects of experimental warming on floral scent, display, and rewards in two subalpine herbs.

Background And Aims: Floral volatiles, visual traits, and rewards mediate attraction and defense in plant-pollinator and plant-herbivore interactions, but these floral traits may be altered by global warming through direct effects of temperature or longer term impacts on plant resources. We examined the effect of warming on floral and leaf volatile emissions, floral morphology, plant height, nectar production, and oviposition by seed predators.

Methods: We used open-top chambers that warmed plants in the field +2-3 °C on average (+6-11 °C increase in daily maxima) for 2-4 weeks across 1-3 years at 3 sites in Colorado, USA.

Evolvability and trait function predict phenotypic divergence of plant populations.

Understanding the causes and limits of population divergence in phenotypic traits is a fundamental aim of evolutionary biology, with the potential to yield predictions of adaptation to environmental change. Reciprocal transplant experiments and the evaluation of optimality models suggest that local adaptation is common but not universal, and some studies suggest that trait divergence is highly constrained by genetic variances and covariances of complex phenotypes. We analyze a large database of population divergence in plants and evaluate whether evolutionary divergence scales positively with standing genetic variation within populations (evolvability), as expected if genetic constraints are evolutionarily important.

Genetic potential for changes in breeding systems: Predicted and observed trait changes during artificial selection for male and female allocation in a gynodioecious species.

Premise: Evolution of separate sexes from hermaphroditism often proceeds through gynodioecy, but genetic constraints on this process are poorly understood. Genetic (co-)variances and between-sex genetic correlations were used to predict evolutionary responses of multiple reproductive traits in a sexually dimorphic gynodioecious species, and predictions were compared with observed responses to artificial selection.

Methods: Schiedea (Caryophyllaceae) is an endemic Hawaiian lineage with hermaphroditic, gynodioecious, subdioecious, and dioecious species.

Genetic and spatial variation in vegetative and floral traits across a hybrid zone.

Premise: Genetic variation influences the potential for evolution to rescue populations from impacts of environmental change. Most studies of genetic variation in fitness-related traits focus on either vegetative or floral traits, with few on floral scent. How vegetative and floral traits compare in potential for adaptive evolution is poorly understood.

Feasibility and efficacy of a remotely delivered fall prevention exercise program for community-dwelling older adults with cancer: Protocol for the STABLE trial.

Falls are a major issue in older adults with cancer due to the effects of cancer and its treatments. Ample evidence in the general population of older adults has demonstrated the effectiveness of strength and balance training in reducing fall rates in older adults. However, data on effective fall prevention interventions in the oncology setting are lacking.

Selection of Floral Traits by Pollinators and Seed Predators during Sequential Life History Stages.

AbstractOrganismal traits often influence fitness via interactions with multiple species. That selection is not necessarily predictable from pairwise interactions, such as when interactions occur during different life cycle stages. Theoretically, directional selection during two sequential episodes (e.

Phenotypic plasticity and selection on leaf traits in response to snowmelt timing and summer precipitation.

Vegetative traits of plants can respond directly to changes in the environment, such as those occurring under climate change. That phenotypic plasticity could be adaptive, maladaptive, or neutral. We manipulated the timing of spring snowmelt and amount of summer precipitation in factorial combination and examined responses of specific leaf area (SLA), trichome density, leaf water content (LWC), photosynthetic rate, stomatal conductance and intrinsic water-use efficiency (iWUE) in the subalpine herb Ipomopsis aggregata.

Variation in floral volatiles across time, sexes, and populations of wind-pollinated Schiedea globosa.

Premise: Floral scent is a key aspect of plant reproduction, but its intraspecific variation at multiple scales is poorly understood. Sexual dimorphism and temporal regulation of scent can be shaped by evolution, and interpopulation variation may be a bridge to species differences. We tested whether intraspecific chemical diversity in a wind-pollinated species where selection from biotic pollination is absent is associated with genetic divergence across the Hawaiian archipelago.

Water availability affects the relationship between pollen intensity and seed production.

Seed production can be affected by water availability and also depend on the amount (pollen intensity) and quality of pollen deposited. The way pollen receipt on the stigma translates into seeds produced follows that of a saturating dose-response. Not only can water availability and pollen intensity each influence seed production, these factors could interact in their effects on seed production.

Feasibility of a Remotely Delivered Strength and Balance Training Program for Older Adults with Cancer.

Falls are a major issue among older adults with cancer and lead to interruptions in cancer treatment. Resistance and balance training can prevent falls in older adults, but minimal evidence is available regarding the older cancer population, who often have unique risk factors. We used a pre-post design to assess the feasibility of a remotely delivered exercise program that progressed in difficulty and its efficacy on lower body strength, balance, and falls in older adults with cancer who had prior in-person exercise experience.

Oncology clinic nurses' attitudes and perceptions regarding implementation of routine fall assessment and fall risk screening: A survey study.

Falls in older adults with cancer are often under-recognized and under-reported. The objective of this study was to explore oncology clinic nurses' willingness and perceived barriers to implement routine falls assessment and falls screening in their practice. Nurses working in outpatient oncology clinics were invited to complete an online survey.

Earlier snow melt and reduced summer precipitation alter floral traits important to pollination.

Climate change can cause changes in expression of organismal traits that influence fitness. In flowering plants, floral traits can respond to drought, and that phenotypic plasticity has the potential to affect pollination and plant reproductive success. Global climate change is leading to earlier snow melt in snow-dominated ecosystems as well as affecting precipitation during the growing season, but the effects of snow melt timing on floral morphology and rewards remain unknown.

Floral Scent Composition and Fine-Scale Timing in Two Moth-Pollinated Hawaiian (Caryophyllaceae).

Floral scent often intensifies during periods of pollinator activity, but the degree of this synchrony may vary among scent compounds depending on their function. Related plant species with the same pollinator may exhibit similar timing and composition of floral scent. We compared timing and composition of floral volatiles for two endemic Hawaiian plant species, and (Caryophyllaceae).

Pollinator visitation rate and effectiveness vary with flowering phenology.

Premise: Flowering time may influence pollination success and seed set through a variety of mechanisms, including seasonal changes in total pollinator visitation or the composition and effectiveness of pollinator visitors.

Methods: We investigated mechanisms by which changes in flowering phenology influence pollination and reproductive success of Mertensia ciliata (Boraginaceae). We manipulated flowering onset of potted plants and assessed the frequency and composition of pollinator visitors, as well as seed set.

A Closer Look at the Introduction of the NCLEX-RN in Canada.

In 2015, the nursing faculty across most of Canada were informed by provincial nursing regulators that the America-based National Council Licensure Examination-Registered Nurse (NCLEX-RN) was going to replace the Canadian Registered Nurse Examination for our nursing students to become registered as nurses. This change in the exam has presented a number of challenges to both faculty and students as they transitioned from a Canadian exam for the Canadian context to an exam that was originally formulated for nursing registration in the United States. This manuscript examines the differences in the Canadian and American healthcare systems; explores the variations in Canadian and American nursing practice and education; outlines concerns surrounding the use of standardized testing that panders to corporate interests, encourages "teaching to the test" and is costing nursing programs and nursing students considerable resources; and explores the controversy surrounding the validity of the NCLEX-RN in both Canada and the United States.

Early snowmelt projected to cause population decline in a subalpine plant.

How climate change influences the dynamics of plant populations is not well understood, as few plant studies have measured responses of vital rates to climatic variables and modeled the impact on population growth. The present study used 25 y of demographic data to analyze how survival, growth, and fecundity respond to date of spring snowmelt for a subalpine plant. Fecundity was estimated by seed production (over 15 y) and also divided into flower number, fruit set, seeds per fruit, and escape from seed predation.

Water influences how seed production responds to conspecific and heterospecific pollen.

Premise: Outcrossing species depend on pollen from conspecific individuals that may not be exposed to the same abiotic conditions as maternal plants. Additionally, many flowers receive heterospecific pollen, which can also influence seed production. Studies aimed to understand how abiotic conditions influence seed production tend to focus on maternal conditions and leave unexplored the effect of abiotic conditions experienced by pollen donors.

Phenotypic plasticity of floral volatiles in response to increasing drought stress.

Background And Aims: Flowers emit a wide range of volatile compounds which can be critically important to interactions with pollinators or herbivores. Yet most studies of how the environment influences plant volatiles focus on leaf emissions, with little known about abiotic sources of variation in floral volatiles. Understanding phenotypic plasticity in floral volatile emissions has become increasingly important with globally increasing temperatures and changes in drought frequency and severity.

Clines in traits compared over two decades in a plant hybrid zone.

Background And Aims: Clines in traits across hybrid zones reflect a balance between natural selection and gene flow. Changes over time in average values for traits, and especially the shapes of their clines, are rarely investigated in plants, but could result from evolution in an unstable hybrid zone. Differences in clines between floral and vegetative traits could indicate different strengths of divergent selection.