Drift in small populations predicts mate availability and the breakdown of self-incompatibility in a clonal polyploid.

Mate limitation in small populations can reduce reproductive fitness, hinder population growth, and increase extinction risk. Mate limitation is exacerbated in self-incompatible (SI) taxa, where shared S-alleles further restrict mating. Theory suggests genetic drift as a predictor of mate limitation and the breakdown of SI systems.

Behavioural Thermoregulation of Flowers via Petal Movement.

Widely documented in animals, behavioural thermoregulation mitigates negative impacts of climate change. Plants experience especially strong thermal variability but evidence for plant behavioural thermoregulation is limited. Along a montane elevation gradient, Argentina anserina flowers warm more in alpine populations than at lower elevation.

An elevational cline in leaf variegation: Testing anti-herbivory and abiotic heterogeneity hypotheses in maintaining a polymorphism.

Premise: While some studies have found leaf variegation to reduce photosynthetic capacity, others showed that it can increase photosynthesis. Thus, what maintains variegation remains an open question. Two primary hypotheses-the anti-herbivory and abiotic heterogeneity hypotheses-have been posited, yet little empirical research explicitly investigates the maintenance of naturally occurring variegation.

Effective population size mediates the impact of pollination services on pollen limitation.

Inadequate pollen receipt limits flowering plant reproduction worldwide. Ecological causes of pollen limitation (PL), like pollinator scarcity and low plant abundance, have been a primary research focus. The genetic diversity of plant populations could impact both quantity and quality components of PL in concert with ecological factors, yet empirical examples are lacking.

Divergent gametic thermal performance and floral warming across an elevation gradient.

Thermal environments vary widely across species ranges, establishing the potential for local adaptation of thermal performance optima and tolerance. In the absence of local adaptation, selection should favor mechanisms to meet thermal optima. Floral temperature is a major determinant of reproductive success in angiosperms, yet whether gametic thermal performance shows signatures of local adaptation across temperature gradients, and how variation in gametic thermal performance influences floral evolution, is unknown.

Drivers of strong isolation and small effective population size at a leading range edge of a widespread plant.

Climate change has influenced species distributions worldwide with upward elevational shifts observed in many systems. Leading range edge populations, like those at upper elevation limits, are crucial for climate change responses but can exhibit low genetic diversity due to founder effects, isolation, or limited outbreeding. These factors can hamper local adaptation at range limits.

Disentangling the components of pollen limitation in a widespread herb with gametophytic self-incompatibility.

Premise: Seed production is frequently limited by the receipt of insufficient or low-quality pollen, collectively termed "pollen limitation" (PL). In taxa with gametophytic self-incompatibility (GSI), incompatible pollen can germinate on stigmas but pollen tubes are arrested in styles. This allows for estimates of pollen performance before, during, and after self-recognition, as well as insight into the factors underlying pollen quality limitation in GSI taxa.

Hybrid breakdown is elevated near the historical cores of a species' range.

New species form when they become reproductively isolated. A classic model of speciation posits that derived mutations appear in isolated populations and reduce fitness when combined in hybrids. While these Bateson-Dobzhansky-Muller incompatibilities are known to accumulate as populations diverge over time, they may also reflect the amount of standing genetic variation within populations.

Reply to Robson et al.

Robson et al.'s commentary on our article, 'Floral pigmentation has responded rapidly to global change in ozone and temperature', questions the study's conclusion that floral ultraviolet (UV) pigmentation has responded to global change, particularly to total column ozone (TCO). Robson et al.

A test of Sensory Drive in plant-pollinator interactions: heterogeneity in the signalling environment shapes pollinator preference for a floral visual signal.

Sensory Drive predicts that habitat-dependent signal transmission and perception explain the diversification of communication signals. Whether Sensory Drive shapes floral evolution remains untested in nature. Pollinators of Argentina anserina prefer small ultraviolet (UV)-absorbing floral guides at low elevation but larger guides at high.

The effects of climate change on floral anthocyanin polymorphisms.

Pigmentation affords resistance to abiotic stressors, and thus can respond adaptively or plastically to drought and extreme temperatures associated with global change. Plants frequently display variability in flower coloration that is underlain by anthocyanin pigmentation. While anthocyanin polymorphisms impact plant-animal interactions, they also impact reproductive performance under abiotic stress.

Floral Color Properties of Serpentine Seep Assemblages Depend on Community Size and Species Richness.

Functional traits, particularly those that impact fitness, can shape the ecological and evolutionary relationships among coexisting species of the same trophic level. Thus, examining these traits and properties of their distributions (underdispersion, overdispersion) within communities can provide insights into key ecological interactions (e.g.

Westward range expansion from middle latitudes explains the Mississippi River discontinuity in a forest herb of eastern North America.

It is often expected that temperate plants have expanded their geographical ranges northward from primarily southern refugia. Evidence for this hypothesis is mixed in eastern North American species, and there is increasing support for colonization from middle latitudes. We studied genome-wide patterns of variation in RADseq loci to test hypotheses concerning range expansion in a North American forest herb (Campanula americana).

Floral Pigmentation Has Responded Rapidly to Global Change in Ozone and Temperature.

Across kingdoms, organisms ameliorate UV stress by increasing UV-absorbing pigmentation. Rapid ozone degradation during the 20 century resulted in elevated UV incidence, but pigmentation responses to this aspect of global change have yet to be demonstrated. In flowering plants, UV exposure favors larger areas of UV-absorbing pigmentation on petals, which protects pollen from UV-damage.

Geographic Variation in Floral Color and Reflectance Correlates With Temperature and Colonization History.

Petal color variation within species is common and may be molded by abiotic or biotic selection pressures, or neutral population structure. For example, darker flowers may be favored in cooler environments because they absorb more solar radiation, elevating the temperature of reproductive structures. Additionally, flower color may evolve to attract the dominant or most efficient pollinator type in a given population.

Macroevolution of Flower Color Patterning: Biased Transition Rates and Correlated Evolution with Flower Size.

Floral pigmentation patterns can both mediate plant-pollinator interactions and modify the abiotic environment of reproductive structures. To date, there have been no inquiries into the rate and directionality of macroevolutionary transitions between patterned and non-patterned petals despite their ecological importance and ubiquity across angiosperms. Petals in the Potentilleae tribe (Rosaceae) display color patterns in the ultraviolet (UV) and human-visible spectrum, or can be uniform in color (i.

The role of sensory drive in floral evolution.

Sensory drive theory posits that the evolution of communication signals is shaped by the sensory systems of receivers and the habitat conditions under which signals are received. It has inspired an enormous body of research, advancing our understanding of signal evolution and speciation in animals. In plants, the extreme diversification of floral signals has fascinated biologists for over a century.

Pollen colour morphs take different paths to fitness.

Colour phenotypes are often involved in communication and are thus under selection by species interactions. However, selection may also act on colour through correlated traits or alternative functions of biochemical pigments. Such forms of selection are instrumental in maintaining petal colour diversity in plants.

Selfing ability and drift load evolve with range expansion.

Colonization at expanding range edges often involves few founders, reducing effective population size. This process can promote the evolution of self-fertilization, but implicating historical processes as drivers of trait evolution is often difficult and requires an explicit model of biogeographic history. In plants, contemporary limits to outcrossing are often invoked as evolutionary drivers of self-fertilization, but historical expansions may shape mating system diversity, with leading-edge populations evolving elevated selfing ability.

The thermal ecology of flowers.

Background: Obtaining an optimal flower temperature can be crucial for plant reproduction because temperature mediates flower growth and development, pollen and ovule viability, and influences pollinator visitation. The thermal ecology of flowers is an exciting, yet understudied field of plant biology.

Scope: This review focuses on several attributes that modify exogenous heat absorption and retention in flowers.