Sharks are a diverse group of mobile predators that forage across varied spatial scales and have the potential to influence food web dynamics. The ecological consequences of recent declines in shark biomass may extend across broader geographic ranges if shark taxa display common behavioural traits. By tracking the original site of photosynthetic fixation of carbon atoms that were ultimately assimilated into muscle tissues of 5,394 sharks from 114 species, we identify globally consistent biogeographic traits...

Accumulating evidence indicates that biodiversity has an important impact on parasite evolution and emergence. The vast majority of studies in this area have only considered the diversity of species within an environment as an overall measure of biodiversity, overlooking the role of genetic diversity within a particular host species. Although theoretical models propose that host genetic diversity in part shapes that of the infecting parasite population, and hence modulates the risk of parasite emergence, this...

High-resolution visualization of short non-repetitive DNA in situ in the nuclear genome is essential for studying looping interactions and chromatin organization in single cells. Recent advances in fluorescence in situ hybridization (FISH) using Oligopaints probes enabled super-resolution imaging of genomic domains with a resolution limit of 4.9 kb. To target shorter elements, we developed a simple FISH method that uses only molecular beacon (MB) probes to facilitate the probe-target binding, while minimizing non-specific fluorescence. We...

Multiple subtypes of avian influenza (AI) and novel reassortants are frequently isolated from live bird markets (LBMs). However, our understanding of the drivers of persistence of multiple AI subtypes is limited. We propose a stochastic model of AI transmission within an LBM that incorporates market size, turnover rate and the balance of direct versus environmental transmissibility. We investigate the relationship between these factors and the critical community size (CCS) for the persistence of single and...

Biogeographic distributions are driven by cumulative effects of smaller scale processes. Thus, vulnerability of animals to thermal stress is the result of physiological sensitivities to body temperature (Tb), microclimatic conditions, and behavioural thermoregulation. To understand interactions among these variables, we analysed the thermal tolerances of three species of intertidal snails from different latitudes along the Chinese coast, and estimated potential Tb in different microhabitats at each site. We then empirically determined the temperatures at which...

Biotic interactions underlie ecosystem structure and function, but predicting interaction outcomes is difficult. We tested the hypothesis that biotic interaction strength increases toward the equator, using a global experiment with model caterpillars to measure predation risk. Across an 11,660-kilometer latitudinal gradient spanning six continents, we found increasing predation toward the equator, with a parallel pattern of increasing predation toward lower elevations. Patterns across both latitude and elevation were driven by arthropod predators, with no systematic...

Background: In early 2013, a novel avian-origin influenza A(H7N9) virus emerged in China, and has caused sporadic human infections. The incubation period is the delay from infection until onset of symptoms, and varies from person to person. Few previous studies have examined whether the duration of the incubation period correlates with subsequent disease severity. Methods and Findings: We analyzed data of period of exposure on 395 human cases of laboratory-confirmed influenza A(H7N9) virus infection in...

Vegetative propagation (clonal growth) conveys several evolutionary advantages that positively affect life history fitness and is a widespread phenomenon among angiosperms that also reproduce sexually. However, a bias towards clonality can interfere with sexual reproduction and lead to sexual extinction, although a dearth of effective genetic tools and mathematical models for clonal plants has hampered assessment of these impacts. Using the endangered tropical epiphytic or lithophytic orchid Bulbophyllum bicolor as a model, we integrated an...

Objectives: We aimed to describe patterns in the usage of antivirals to treat influenza virus infection in hospitals in Hong Kong from 2000 through 2015. Methods: We analyzed centralized electronic health records that included dispensation information and diagnosis codes. Information collected on admissions included patient age, sex, admission year and month, and medications dispensed, and were matched with the first 15 discharge diagnosis codes. We divided monthly admission episodes by relevant population denominators to obtain...

Behavioural decisions are often context-dependent, where information from immediate experience is incorporated into an individual's decision-making, particularly in complex environments. To test whether such mechanism is adopted by foragers in heterogeneous environments, we investigated the foraging behaviour of the deposit-feeding sand-bubbler crab, Scopimera intermedia. An individual-based model was constructed, based on an optimal-patch selection criterion, which implicitly assumed that individuals adjust foraging decisions based on immediate past experience. The model's predictions were tested on the...

Mating preference can be a driver of sexual selection and assortative mating and is, therefore, a key element in evolutionary dynamics. Positive mating preference by similarity is the tendency for the choosy individual to select a mate which possesses a similar variant of a trait. Such preference can be modelled using Gaussian-like mathematical functions that describe the strength of preference, but such functions cannot be applied to empirical data collected from the field. As a...

Background: Hand, foot and mouth disease (HFMD) is a common illness in China that mainly affects infants and children. The objective of this study is to assess the economic cost and health-related quality of life associated with HFMD in China. Method: A telephone survey of caregivers were conducted in 31 provinces across China. Caregivers of laboratory-confirmed HFMD patients who were registered in the national HFMD enhanced surveillance database during 2012-2013 were invited to participate in...

Multichannel feeding, whereby consumers feed across resource channels such as upon herbivore and detritivore resources, acts to link discrete compartments of a food web with implications for ecosystem functioning and stability. Currently however, we have little understanding which feeding strategies of consumers underlie multichannel feeding. We therefore link spider functional group and resource density-dependent or density-independent feeding strategies to multichannel feeding by quantifying not only consumer diet, but also the relative availability of resources. Here...

Climate change related risks and impacts on ectotherms will be mediated by habitats and their influence on local thermal environments. While many studies have documented morphological and genetic aspects of niche divergence across habitats, few have examined thermal performance across such gradients and directly linked this variation to contemporary climate change impacts. In this study, we quantified variation in thermal performance across a gradient from forest to gallery forest-savanna mosaic in Cameroon for a skink...