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The resource rule hypothesis predicts that geographic differences in body size among populations of organisms are due to the amount, availability, and quality of food resources. For instance, the body size of large herbivores is often correlated with soil characteristics because better soils produce better forage. In semiarid environments, rainfall variation is an important driver of forage availability, especially highly nutritious annual forbs. Thus, in such pulsed‐resource environments, it is unclear whether the body size of large herbivores is influenced by fixed resources correlated with soil characteristics, irregular resource pulses correlated with rainfall, or both. Furthermore, it is not clear whether phenotypic expression is a function of forage quality or quantity. During the early autumns of 2011–2018, we captured 4554 white‐tailed deer (Odocoileus virginianus) on seven rangeland sites in the semiarid climate of South Texas, USA. The sites range from coastal to 140 km inland and represent gradients in both soil texture and annual rainfall. We recorded age‐ and sex‐specific indices of skeletal size, antler size, and body mass. Site‐specific soil characteristics explained most of the variation in skeletal size; percent sand was inversely related to skeletal size. For environmentally sensitive phenotypes (antler size and body mass), both soil characteristics and rainfall were influencers; increases in rainfall reduced the negative effect of sand. Percent sand and rainfall were positively correlated with annual biomass of preferred forbs, yet all phenotypic traits declined with increases in forb quantity. Increases in percent shrub cover increased all phenotype sizes. Our data suggest that the phenotypic expression of large herbivores in semiarid environments is driven by forage quality via edaphic characteristics rather than forage quantity via rainfall. Specifically, less sand in the soil allows for the development of shrub communities, which in turn provide a consistent source of forage in a variable, pulsed‐rainfall environment. Although forbs are of higher quality, they are highly ephemeral. The availability of a consistent source of forage may enable white‐tailed deer to extend time invested in body growth, which results in greater phenotype size. Our findings align with the resource rule hypothesis that identifies resource availability as a fundamental element explaining geographical variation in phenotypic expression. [ABSTRACT FROM AUTHOR]

The advent of complex multicellularity (CM) was a pivotal event in the evolution of animals, plants and fungi. In the fungal Ascomycota, CM is based on hyphal filaments and arose in the Pezizomycotina. The genus Neolecta defines an enigma: phylogenetically placed in a related group containing mostly yeasts, Neolecta nevertheless possesses Pezizomycotina-like CM. Here we sequence the Neolecta irregularis genome and identify CM-associated functions by searching for genes conserved in Neolecta and the Pezizomycotina, which are absent or divergent in budding or fission yeasts. This group of 1,050 genes is enriched for functions related to diverse endomembrane systems and their organization. Remarkably, most show evidence for divergence in both yeasts. Using functional genomics, we identify new genes involved in fungal complexification. Together, these data show that rudimentary multicellularity is deeply rooted in the Ascomycota. Extensive parallel gene divergence during simplification and constraint leading to CM suggest a deterministic process where shared modes of cellular organization select for similarly configured organelle- and transport-related machineries.

Infectious disease outbreaks related to outdoor sporting events are an underacknowledged environmental health risk. We reviewed documented instances of sporting events that led to outbreaks of illness due to interactions of athletes with environmental pathogen reservoirs such as soil or water. We note that aspects of outdoor athletic activities can mediate a suppression in immune function. The implications of this review are of particular interest to environmental health professionals and healthcare professionals, as they show that populations of young, otherwise healthy adult athletes and other members of their communities are a contextually at-risk group to be aware of in order to improve and speed ability to cluster individuals in outbreaks, and for diagnosis and prevention for individual patients. This review highlights an opportunity where environmental health professionals can provide a critical linkage between patients and the environment., Introduction: Risk Factors of Infection for the Outdoor Athlete Contact with environmental sources of pathogens provides numerous avenues--directly and indirectly--for infection and illness. In the case of participants in outdoor [...]

Proof-of-concept (POC) clinical trials play an important role in developing novel treatments and determining whether existing treatments may be efficacious in broader populations of patients. The goal of most POC trials is to determine whether a treatment is likely to be efficacious for a given indication and thus whether it is worth investing the financial resources and participant exposure necessary for a confirmatory trial of that intervention. A challenge in designing POC trials is obtaining sufficient information to make this important go/no-go decision in a cost-effective manner. An IMMPACT consensus meeting was convened to discuss design considerations for POC trials in analgesia, with a focus on maximizing power with limited resources and participants. We present general design aspects to consider including patient population, active comparators and placebos, study power, pharmacokinetic-pharmacodynamic relationships, and minimization of missing data. Efficiency of single-dose studies for treatments with rapid onset is discussed. The trade-off between parallel-group and crossover designs with respect to overall sample sizes, trial duration, and applicability is summarized. The advantages and disadvantages of more recent trial designs, including N-of-1 designs, enriched designs, adaptive designs, and sequential parallel comparison designs, are summarized, and recommendations for consideration are provided. More attention to identifying efficient yet powerful designs for POC clinical trials of chronic pain treatments may increase the percentage of truly efficacious pain treatments that are advanced to confirmatory trials while decreasing the percentage of ineffective treatments that continue to be evaluated rather than abandoned.