Virome characterization of game animals in China reveals a spectrum of emerging pathogens

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Elevational trends in butterfly phenology: implications for species responses to climate change

1. Impacts of global change on the distribution, abundance, and phenology of species have been widely documented. In particular, recent climate change has led to widespread changes in animal and plant seasonality, leading to debate about its potential to cause phenological mismatches among interacting taxa. 2. In mountainous regions, populations of many species show pronounced phenological gradients over short geographic distances, presenting the opportunity to test for effects of climate on phenology, independent of variation in confounding factors such as photoperiod. 3. Here we show for 32 butterfly species sampled for five years over a 1700 m gradient (560–2260 m) in a Mediterranean mountain range that, on average, annual flight period is delayed with elevation by 15–22 days per kilometre. Species mainly occurring at low elevations in the region, and to some extent those flying earlier in the year, showed phenological delays of 23–36 days per kilometre, whereas the flight periods of species that occupy high elevations, or fly in late summer, were consistently more synchronised over the elevation gradient. 4. Elevational patterns in phenology appear to reflect a narrowing phenological window of opportunity for larval and adult butterfly activity of high elevation and late‐flying species. 5. Here, we speculate as to the causes of these patterns, and the consequences for our ability to predict species responses to climate change. Our results raise questions about the use of space–time substitutions in predicting phenological responses to climate change, since traits relating to flight period and environmental associations may influence the capacity of species to adapt to changing climates.     

Electronic fraction collector used for insect sampling in the photoperiod-induced diel emergence of bark beetles

ABSTRACT. An electronic timer and fraction collector consisting of CMOS integrated circuits is described. It converts 50- or 60-Hz AC to real-time pulses in programmable whole-number increments (1, 10 or 60s) from 3 to 16659, producing timing periods from 3 s to more than 11 days. The fraction collector contains a leaf-switch feedback circuit that automatically adjusts to various gear motor speeds and sample tube spacings so that proper positioning results. Hourly collections by the device of the bark beetles Ips typographus L. and Pityogenes chalcographus L. (Scolytidae) emerging from logs of Norway spruce, Picea abies , indicated that both species emerged with a diel periodicity. A unimodal emergence peak for both sexes of both species occurred at midday in LD 20:4 at a constant 25°C and 80% r.h.     

Survival and emergence pattern of sea trout fry in substrata of different compositions

The emergence of the sea trout Salmo trutta fry of Gotland, Sweden, was studied in the laboratory. The main limiting factor for survival up to hatching was the interstitial oxygen concentration, which depends on the gravel permeability, therefore on the substratum granulometry. Fry emergence was possible in substrata in which the geometric mean particle diameter ( d _g) was >15 mm and in substrata in which d _g was <6 mm. In the substrata of low d _g, emergence took place earlier than in the other ones. As a consequence the fry were smaller and their yolk sac only partially resorbed. In an unfavourable environment, fry started to emerge as soon as they reacted positively to light, about 2 weeks after hatching.     

Faster intrinsic rate of torque development in elbow flexors than knee extensors: Effect of muscle architecture?

We studied the effect of pennate vs. fusiform muscle architecture on the rate of torque development (RTD) by examining the predominately fusiform elbow flexors (EF) and highly-pennate knee extensors (KE). Seventeen male volunteers (28.4 ± 6.2 years) performed explosive isometric EF and KE contractions (MVCs). Biceps brachii and vastus lateralis fascicle angles were measured to confirm their architecture, and both the rate of voluntary muscle activation (root-mean-square EMG in the 50 ms before contraction onset; EMG_-50) and electromechanical delay (EMD; depicting muscle-tendon series elasticity) were assessed as control variables to account for their influence on RTD. MVC torque, early (RTD₅₀) and late (RTD₂₀₀) RTDs were calculated and expressed as absolute and normalized values. Absolute MVC torque (+412%), RTD₅₀ (+215%), and RTD₂₀₀ (+427%) were significantly (p < 0.001) higher in KE than EF. However, EF RTD₅₀ was faster (+178%) than KE after normalization (p = 0.02). EMG_-50 and EMD did not differ between muscle groups. The results suggest that the faster absolute RTD in KE is largely associated with its higher maximal torque capacity, however in the absence of differences in rates of muscle activation, fiber type, and EMD the fusiform architecture of EF may be considered a factor allowing its faster early RTD relative to strength capacity.     

Competitiveness of transgenic sugar beet resistant to beet necrotic yellow vein virus and potential impact on wild beet populations

Beets are a crop of particular concern regarding invasiveness questions because they commonly become feral due to unintentional hybridization with annual forms of wild beets. In this study the performance of transgenic beets resistant to Beet Necrotic Yellow Vein Virus (BNYVV) was compared to the performance of unmodified material from the same breeding line. Both transgenic and control genotypes were also compared to a conventionally bred variety carrying a similar phenotypic trait. Field tests were developed in a step by step fashion in order to study seed emergence and competitiveness in early life stages. The tests quantified the potential ecological advantage of virus resistance under virus and non-virus infestation conditions. In experimental field releases in 1993 and 1994 in Germany, a small but increasingly clear 'additive' ecological advantage of the genetically engineered trait was detected. In both years and all competition treatments, the conventional tolerant variety performed best. An impact of naturalization on natural, nonagricultural habitats may appear in wild beet populations in Italian seed beet production areas. However, a survey of coastal areas of North-Eastern Italy found no virus infestation in 1994, suggesting that an increase in wild beet fitness is unlikely to occur.     

Consensus for experimental design in electromyography (CEDE) project: Single motor unit matrix

The analysis of single motor unit (SMU) activity provides the foundation from which information about the neural strategies underlying the control of muscle force can be identified, due to the one-to-one association between the action potentials generated by an alpha motor neuron and those received by the innervated muscle fibers. Such a powerful assessment has been conventionally performed with invasive electrodes (i.e., intramuscular electromyography (EMG)), however, recent advances in signal processing techniques have enabled the identification of single motor unit (SMU) activity in high-density surface electromyography (HDsEMG) recordings. This matrix, developed by the Consensus for Experimental Design in Electromyography (CEDE) project, provides recommendations for the recording and analysis of SMU activity with both invasive (needle and fine-wire EMG) and non-invasive (HDsEMG) SMU identification methods, summarizing their advantages and disadvantages when used during different testing conditions. Recommendations for the analysis and reporting of discharge rate and peripheral (i.e., muscle fiber conduction velocity) SMU properties are also provided. The results of the Delphi process to reach consensus are contained in an appendix. This matrix is intended to help researchers to collect, report, and interpret SMU data in the context of both research and clinical applications.     

Climate change affects the early-life history of a freshwater turtle in a severely drying region

Freshwater turtles are one of the most threatened vertebrate groups. Climate change is a major threat to these species, with impacts affecting all life-history stages. There is currently a limited understanding of how changes in climate may alter the environmental triggers for hatching and emergence from the nests of freshwater turtle hatchlings. This precludes making predictions about how climate change may impact freshwater turtle recruitment success. The southwestern snake-necked turtle (Chelodina oblonga) is endemic to south-western Australia, a global biodiversity hotspot that has undergone severe climatic drying. Recruitment failure is thought to be occurring in many populations of the species. However, there is little understanding as to how environmental change may be influencing recruitment. This study aimed to: (1) determine the incubation duration and hatching and hatchling emergence success of C. oblonga, (2) determine if the species exhibits hatching or emergence synchrony and/or delayed emergence and (3) quantify the effects of temperature and rainfall on hatchling emergence. Using this information, the study assesses how climatic drying and warming may be impacting C. oblonga's early life-history. Between 2018 and 2020 nest sites were monitored around a large urban wetland with weekly assessments of egg and hatchling status. Incubation duration and hatching and hatchling emergence success were calculated, and generalized linear models were built to determine how temperature and/or rainfall predicted emergence. Hatchlings either emerged shortly after hatching or overwintered in the nest, and both hatching and emergence were asynchronous. Both emergence periods were positively associated with temperature and rainfall. This study reveals that incubation duration, hatching success, hatchling emergence and survival are all likely to be impacted by recent and projected climate change, and especially drying. Warming and drying are predicted for many temperate regions globally, and it is therefore important that their impacts on the early life history of freshwater turtles be better understood.     

Life Cycle,Production and Survival Rates of Ptychoptera paludosa(Diptera: Ptychopteridae)

Life cycle, survival and production of the univoltine midge Ptychoptera paludosa whose larvae live in fine sandy sediments were studied in a German stream (1989–1990). Growth of the 4th larval instar was linear. Adults emerge from May, for ca 8 weeks (1985–1990); emergence was 0.56 g dry weight m^–2 lentic area (1990). Density decreased strongly only when larvae were young; except after an exceptional spate, numbers emerging were independent of discharge. Larval survival was ca 9%; only 10% of the potential offspring of the survivors actually appeared in the next generation. Secondary production (P) was 2.3 g ash free dry weight (AFDW) m^–2y^–1, mean biomass (B) was 0.6 g AFDW m^–2, i.e., the P/B ratio was 3.8.     

Zooming in on Downward Causation

An attempt is made to identify a concept of ‘downward causation’ that will fit the claims of some recent writers and apply to interesting cases in biology and cognitive theory, but not to trivial cases. After noting some difficulties in achieving this task, it is proposed that in interesting cases commonly used to illustrate ‘downward causation’, (a) regularities hold between multiply realizable properties and (b) the explanation of the parallel regularity at the level of the realizing properties is non-trivial. It is argued that the relation between a realizable property and the property that realizes its effect in a particular case is not usefully regarded as a species of causation and that use of the concept of downward causation deflects our attention from our central explanatory tasks.