A unified framework to investigate and interpret hybrid and allopolyploid biodiversity across biological scales.

Premise: Hybridization and polyploidization are common in vascular plants and important drivers of biodiversity by facilitating speciation and ecological diversification. A primary limitation to making broad synthetic discoveries in hybrid and allopolyploid biodiversity research is the absence of a standardized framework to compare data across studies and biological scales.

Methods: Here, I present a new quantitative framework to investigate and interpret patterns in hybrid and allopolyploid biology called the divergence index (DI).

Greater ecophysiological stress tolerance in the core environment than in extreme environments of wild chickpea (Cicer reticulatum).

Global climate change and land use change underlie a need to develop new crop breeding strategies, and crop wild relatives (CWR) have become an important potential source of new genetic material to improve breeding efforts. Many recent approaches assume adaptive trait variation increases towards the relative environmental extremes of a species range, potentially missing valuable trait variation in more moderate or typical climates. Here, we leveraged distinct genotypes of wild chickpea (Cicer reticulatum) that differ in their relative climates from moderate to more extreme and perform targeted assessments of drought and heat tolerance.

Chromosomal evolution, environmental heterogeneity, and migration drive spatial patterns of species richness in (Liliaceae).

We used nuclear genomic data and statistical models to evaluate the ecological and evolutionary processes shaping spatial variation in species richness in (Liliaceae, 74 spp.). occupies diverse habitats in the western United States and Mexico and has a center of diversity in the California Floristic Province, marked by multiple orogenies, winter rainfall, and highly divergent climates and substrates (including serpentine).

Ecophysiological adaptations shape distributions of closely related trees along a climatic moisture gradient.

Tradeoffs between the energetic benefits and costs of traits can shape species and trait distributions along environmental gradients. Here we test predictions based on such tradeoffs using survival, growth, and 50 photosynthetic, hydraulic, and allocational traits of ten Eucalyptus species grown in four common gardens along an 8-fold gradient in precipitation/pan evaporation (P/E) in Victoria, Australia. Phylogenetically structured tests show that most trait-environment relationships accord qualitatively with theory.

Reproductive phases coincide with changes in morphology and photosynthetic physiology in an endangered cycad species.

Cycadales is highly endangered and one of the oldest dioecious gymnosperm lineages, making their reproductive biology highly relevant to conservation efforts and our understanding of the impact of dioecy, yet cycad reproductive ecophysiology is poorly understood. We examined how the costs associated with reproduction may impact basic physiological variation in cycad species. Specifically, we measured traits related to functional morphology and photosynthetic physiology in sterile and fertile staminate plants ('males') of .

Functional traits and trait coordination change over the life of a leaf in a tropical fern species.

Premise: Plant ecological strategies are often defined by the integration of underlying traits related to resource acquisition, allocation, and growth. Correlations between key traits across diverse plants suggest that variation in plant ecological strategies is largely driven by a fast-slow continuum of plant economics. However, trait correlations may not be constant through the life of a leaf, and it is still poorly understood how trait function varies over time in long-lived leaves.

At least it is a dry cold: the global distribution of freeze-thaw and drought stress and the traits that may impart poly-tolerance in conifers.

Conifers inhabit some of the most challenging landscapes where multiple abiotic stressors (e.g., aridity, freezing temperatures) often co-occur.

The ecology and physiology of fern gametophytes: A methodological synthesis.

All green plants alternate between the gametophyte and sporophyte life stages, but only seed-free vascular plants (ferns and lycophytes) have independent, free-living gametophytes. Fern and lycophyte gametophytes are significantly reduced in size and morphological complexity relative to their sporophytic counterparts and have often been overlooked in ecological and physiological studies. Understanding the ecological and physiological factors that directly impact this life stage is of critical importance because the ultimate existence of a sporophyte is dependent upon successful fertilization in the gametophyte generation.

The Impact of Domestication on Aboveground and Belowground Trait Responses to Nitrogen Fertilization in Wild and Cultivated Genotypes of Chickpea ( sp.).

Despite the importance of crop responses to low fertility conditions, few studies have examined the extent to which domestication may have limited crop responses to low-fertility environments in aboveground and belowground traits. Moreover, studies that have addressed this topic have used a limited number of wild accessions, therefore overlooking the genotypic and phenotypic diversity of wild relatives. To examine how domestication has affected the response of aboveground and belowground agronomic traits, we measured root and leaf functional traits in an extensive set of wild and domesticated chickpea accessions grown in low and high nitrogen soil environments.

Global-level population genomics reveals differential effects of geography and phylogeny on horizontal gene transfer in soil bacteria.

Although microorganisms are known to dominate Earth's biospheres and drive biogeochemical cycling, little is known about the geographic distributions of microbial populations or the environmental factors that pattern those distributions. We used a global-level hierarchical sampling scheme to comprehensively characterize the evolutionary relationships and distributional limitations of the nitrogen-fixing bacterial symbionts of the crop chickpea, generating 1,027 draft whole-genome sequences at the level of bacterial populations, including 14 high-quality PacBio genomes from a phylogenetically representative subset. We find that diverse taxa perform symbiosis with chickpea and have largely overlapping global distributions.

A new protocol for psychrometric pressure-volume curves of fern gametophytes.

Premise: Pressurevolume curves are a widely used analytical framework to derive several key physiological traits related to plant-water relations, including a species' turgor loss point, osmotic potential at full turgor, and the elasticity of cell walls. We developed a novel protocol, including the preparation and treatment of fern gametophytes, to generate data for pressurevolume curve analyses using thermocouple psychrometry.

Methods And Results: Gametophytes of the fern species were grown from spore, harvested, and subjected to a series of drying intervals.

Erratum: Sex-specific differences in functional traits and resource acquisition in five cycad species.

[This corrects the article DOI: 10.1093/aobpla/plx013.][This corrects the article DOI: 10.

Ecology and genomics of an important crop wild relative as a prelude to agricultural innovation.

Domesticated species are impacted in unintended ways during domestication and breeding. Changes in the nature and intensity of selection impart genetic drift, reduce diversity, and increase the frequency of deleterious alleles. Such outcomes constrain our ability to expand the cultivation of crops into environments that differ from those under which domestication occurred.

Sex-specific differences in functional traits and resource acquisition in five cycad species.

Selective pressures acting on plant life histories can drive extreme specialization. One example of such specialization is the evolution of dioecious breeding systems. Evolutionary and ecological theory posits that dioecy may subject male and female individuals to different selective pressures and result in unique sex-mediated adaptive traits related to resource allocation and ecophysiology.

A comparison of alcohol-positive and alcohol-negative trauma patients.

Objective: Hospital admission for an alcohol-related traumatic injury may offer a "teachable moment" to address a patient's alcohol problem. Although trauma teams provide a number of other health-related services, there may be characteristics of alcohol-positive victims that act as barriers toward providing alcohol counseling. The purpose of this study was to compare the characteristics and hospital outcomes of trauma patients who tested positive for alcohol at the time of hospital admission with those who did not.