Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
5,794
datasets available to search
ShareScore release 0.9.0
Dataset results
5,794 results for “exposures”
Data from: Sex-specific gene expression in the mouse nucleus accumbens before and after cocaine exposure
Females are more sensitive than males to the addictive effects of cocaine and are more likely to relapse. The nucleus accumbens has a well-established major role in the response to cocaine, and sex-specific differential expression of key transcripts at baseline and after cocaine withdrawal could underlie some of these differences. To address this hypothesis, four groups of mice (cycling females, ovariectomized females treated with estradiol or placebo and males) were evaluated for open field activity following 7 daily injections of saline or cocaine. Sensitization to the locomotor effects of cocaine was most pronounced in ovariectomized mice receiving estradiol, was greater in cycling females than in males, and failed to occur in ovariectomized/placebo mice. After a 28-day period of withdrawal, RNA prepared from the nucleus accumbens of individual cocaine or saline injected mice was subjected to RNASeq analysis. Expression of a substantial fraction of the transcripts expressed in the nucleus accumbens (~3%) differed in cycling female mice when compared to male mice, was altered by ovariectomy or was responsive to estradiol treatment. The transcripts differentially expressed in the nucleus accumbens of cycling female mice withdrawn from cocaine for 28-days exhibited substantial overlap with those differentially expressed in the nucleus accumbens of male mice withdrawn for 7-days. A small set of transcripts were similarly affected by cocaine in placebo or estradiol treated ovariectomized mice. Transcripts differentially expressed after 28-days of withdrawal encoded neprilysin, which degrades enkephalin and other neuropeptides, G protein coupled receptors and secreted proteins such as Wnt2, Fst and Igfbp4.
Data from: Prozac in the water: chronic fluoxetine exposure and predation risk interact to shape behaviors in an estuarine crab
Predators exert considerable top-down pressure on ecosystems by directly consuming prey or indirectly influencing their foraging behaviors and habitat use. Prey is, therefore, forced to balance predation risk with resource reward. A growing list of anthropogenic stressors such as rising temperatures and ocean acidification has been shown to influence prey risk behaviors and subsequently alter important ecosystem processes. Yet, limited attention has been paid to the effects of chronic pharmaceutical exposure on risk behavior or as an ecological stressor, despite widespread detection and persistence of these contaminants in aquatic environments. In the laboratory, we simulated estuarine conditions of the shore crab, Hemigrapsus oregonensis, and investigated whether chronic exposure (60 days) to field-detected concentrations (0, 3, and 30 ng/L) of the antidepressant fluoxetine affected diurnal and nocturnal risk behaviors in the presence of a predator, Cancer productus. We found that exposure to fluoxetine influenced both diurnal and nocturnal prey risk behaviors by increasing foraging and locomotor activity in the presence of predators, particularly during the day when these crabs normally stay hidden. Crabs exposed to fluoxetine were also more aggressive, with a higher frequency of agonistic interactions and increased mortality due to conflicts with conspecifics. These results suggest that exposure to field-detected concentrations of fluoxetine may alter the trade-off between resource acquisition and predation risk among crabs in estuaries. This fills an important data gap, highlighting how intra- and interspecific behaviors are altered by exposure to field concentrations of pharmaceuticals; such data more explicitly identify potential ecological impacts of emerging contaminants on aquatic ecosystems and can aid water quality management.
Data from: Robustness of the outcome of adult bumblebee infection with a trypanosome parasite after varied parasite exposures during larval development
The outcome of defence by the invertebrate immunity has recently been shown to be more complex than previously thought. In particular, the outcome is affected by biotic and abiotic environmental variation, host genotype, parasite genotype, and their interaction. Knowledge of conditions under which environmental variation affects the outcome of an infection is one important question that relates to this complexity. We here use the model system of the bumblebee, Bombus terrestris infected by the trypanosome, Crithidia bombi, combined with a split-colony design to test the influence of the parasite environment during larval rearing on adult resistance. We find that genotype-specific interactions are maintained, and adult resistance is not influenced. This demonstrates that environmental dependence of bumblebee-trypanosome interactions is not ubiquitous, and yet unknown constraints will maintain standard co-evolutionary dynamics under such environmental deviations.
Exposure to a novel predator induces visual predator recognition by naïve prey
<p>The 'life-dinner principle' posits that there is greater selection pressure on the species that have more to lose in an interaction. Thus, based on the asymmetry within predator-prey interactions there is an advantage for prey to learn quickly, especially in response to novel, introduced predators. Here we test the 'learned recognition' hypothesis that posits that naïve prey species' ability to recognize and respond to introduced predators can be induced through experience. We quantified the behavioural response of initially predator naïve burrowing bettongs (<i>Bettongia lesueur</i>) that had been living in the presence (for 8 - 15 months) and absence of an introduced predator (feral cats—<i>Felis catus</i>) to models of cats, a herbivore (rabbit (<i>Oryctolagus cuniculus</i>)), novel object (plastic bucket) and no object (control). We expected that if bettongs recognized cats as a threat they would be more wary in the presence of cat models than either rabbit models, buckets or the control. Bettongs living without predators did not modify their behaviour in response to the cat model, but spent more time cautiously approaching the rabbit model compared to the control. However, bettongs living with cats spent more time cautiously approaching the cat model compared to the rabbit, bucket and control. Our results are consistent with the learned recognition hypothesis which suggests that a predator-naïve prey species ability to recognize novel predators is inducible through experience. Our finding suggests that antipredator responses of reintroduced species could be improved prior to release by exposing them to predators under carefully controlled conditions.</p>
Data from: Antagonistic responses of exposure to sublethal temperatures: adaptive phenotypic plasticity coincides with a reduction in organismal performance
A fitness benefit of phenotypic plasticity is the ability of an organism to survive short-term, deleterious environmental fluctuations. Yet, the influence of selection on plasticity in modulating shifts in phenotypic traits remains unclear. Short-term phenotypic plasticity in thermal tolerance traits is attained by exposure to sublethal hot or cold temperatures (i.e. the hardening response). Heat hardening is expected to buffer organisms from the unpredictability of extreme thermal fluctuations in the environment so as to minimize interruptions in activity and enhance survival. However, exposure to sublethal temperatures might entail other phenotypic costs that constrain or inhibit the prolonged use of hardening responses across longer timescales. Here, we estimated the onset of the heat hardening response, physiological and behavioral shifts during heat hardening, and geographic variation in heat hardening using tree lizards (Urosaurus ornatus). Peak heat hardening occurred 6h after exposure to sublethal temperatures. We found that both preferred body temperatures and locomotor performance diminished following exposure to sublethal temperatures, and performance levels did not approach pre-exposure levels until after the peak hardening response. We also found support for intraspecific variation in the hardening response along an environmental gradient, where populations in more thermally variable environments exhibited stronger plastic responses and populations with higher baseline heat tolerances exhibited weaker plastic responses. Sublethal temperature exposure might induce plasticity in thermal tolerance, however we have characterized other phenotypic shifts that might curtail chronic reliance on plasticity in thermal traits as a mechanism of responding to changes in thermal environments induced by climate warming.
Data from: The association between exposure to environmental bisphenol A and gonadotropic hormone levels among men
Bisphenol A (BPA) is an extensively used chemical with endocrine disrupting properties. Although animal and in vivo studies have suggested possible effects of BPA on levels of gonadotropic hormones, human studies are limited and inconclusive. The study examined whether environmental BPA exposure was associated with gonadotropic hormones levels in men. A total of 560 men aged 18–55 years were recruited from Sandu County, Guizhou Province, China. We collected urine samples for measurement of BPA, and blood samples for measurement of reproductive hormones. We examined serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), and total testosterone (T). Relative risk (RR) was obtained by log-binominal regression to explore the association between urinary BPA level and hormone levels. BPA was detected in 70.4% of urine samples, with a geometric mean of 0.50 μg/gCr. Men with detectable levels of BPA had a 1.52-fold increased risk of having a high LH level (>75th percentile) when compared with men with undetectable levels of BPA, after adjustment for potential confounders (95% confidence interval (CI): 1.04–2.21). The association persisted and slightly intensified among current smokers (adjusted RR (aRR) = 1.76, 95%CI: 1.05–2.95), while it weakened among non-smokers (aRR = 1.17, 95%CI: 0.69–1.96). Urinary BPA level was associated with an increased FSH level among smokers (aRR = 1.64, 95%CI: 1.01–2.67). Urinary BPA level was inversely associated with total T level among males with body max index (BMI) ≥25 kg/m2 although this association was of borderline significance (aRR = 0.52, 95%CI: 0.26–1.05). In conclusion, environmental exposure to BPA was associated with increased serum levels of LH and FSH in male smokers, along with decreased serum levels of total T in men with BMI≥25 kg/m2. These findings suggest that the effects of environmental BPA exposure on hormone levels might be modified by smoking and BMI.
Data from: Effects of multi-generational stress exposure and offspring environment on the expression and persistence of transgenerational effects in Arabidopsis thaliana
Plant phenotypes can be affected by environments experienced by their parents. Parental environmental effects are reported for the first offspring generation and some studies showed persisting environmental effects in second and further offspring generations. However, the expression of these transgenerational effects proved context-dependent and their reproducibility can be low. Here we study the context-dependency of transgenerational effects by evaluating parental and transgenerational effects under a range of parental induction and offspring evaluation conditions. We systematically evaluated two factors that can influence the expression of transgenerational effects: single- versus multiple-generation exposure and offspring environment. For this purpose, we exposed a single homozygous Arabidopsis thaliana Col-0 line to salt stress for up to three generations and evaluated offspring performance under control and salt conditions in a climate chamber and in a natural environment. Parental as well as transgenerational effects were observed in almost all traits and all environments and traced back as far as great-grandparental environments. The length of exposure exerted strong effects; multiple-generation exposure often reduced the expression of the parental effect compared to single-generation exposure. Furthermore, the expression of transgenerational effects strongly depended on offspring environment for rosette diameter and flowering time, with opposite effects observed in field and greenhouse evaluation environments. Our results provide important new insights into the occurrence of transgenerational effects and contribute to a better understanding of the context-dependency of these effects.
Bacterial exposure mediates developmental plasticity and resistance to lethal Vibrio lentus Infection in purple sea urchin (Strongylocentrotus purpuratus) larvae
<p>Exposure to and colonization by bacteria during development have wide-ranging beneficial effects on animal biology but can also inhibit growth or cause disease. The immune system is the prime mediator of these microbial interactions and is itself shaped by them. Studies using diverse animal taxa have begun to elucidate the mechanisms underlying the acquisition and transmission of bacterial symbionts and their interactions with developing immune systems. Moreover, the contexts of these associations are often confounded by stark differences between 'wild type' microbiota and the bacterial communities associated with animals raised in conventional or germ-free laboratories. In this study, we investigate the spatio-temporal kinetics of bacterial colonization and associated effects on growth and immune function in larvae of the purple sea urchin (Strongylocentrotus purpuratus) as a model for host-microbe interactions and immune system development. We also compare the host-associated microbiota of developing embryos and larvae raised in natural seawater or exposed to adult-associated bacteria in the laboratory. Bacteria associated with zygotes, embryos, and early larvae are detectable with 16S amplicon sequencing, but 16S-FISH indicates that the vast majority of larval bacterial load is acquired after feeding begins and is localized to the gut lumen. The bacterial communities of laboratory-cultured embryos are significantly less diverse than the natural microbiota but recapitulate its major components (Alphaproteobacteria, Gammaproteobacteria, and Bacteroidetes), suggesting that biologically relevant host-microbe interactions can be studied in the laboratory. We also demonstrate that bacterial exposure in early development induces changes in morphology and in the immune system. In the absence of bacteria, larvae grow larger at the 4-arm stage. Additionally, bacteria-exposed larvae are significantly more resistant to lethal infection with the larva-associated pathogen Vibrio lentus suggesting that early exposure to high levels of microbes, as would be expected in natural conditions, affects the immune state in later larvae. These results expand our knowledge of microbial influences on early sea urchin development and establish a model in which to study the interactions between the developing larval immune system and the acquisition of larval microbiota.</p>
Data from: Simultaneous exposure to a pulsed and a prolonged anthropogenic stressor can alter consumer multifunctionality
Ecosystems face multiple anthropogenic threats globally, and the effects of these environmental stressors range from individual-level organismal responses to altered system functioning. Understanding the combined effects of stressors on process rates mediated by individuals in ecosystems would greatly improve our ability to predict organismal multifunctionality (e.g. multiple consumer-mediated functions). We conducted a laboratory experiment to test direct and indirect, as well as immediate and delayed effects of a heat wave (pulsed stress) and micropollutants (MPs) (prolonged stress) on individual consumers (the great pond snail Lymnaea stagnalis) and their multifunctionality (i.e. consumption of basal resources, growth, reproduction, nutrient excretion and organic-matter cycling). We found that stressful conditions increased the process rates of multiple functions mediated by individual consumers. Specifically, the artificial heat wave increased process rates in the majority of the quantified functions (either directly or indirectly), whereas exposure to MPs increased consumption of basal resources which lead to increases in the release of nutrients and fine particulate organic matter. Moreover, snails exposed to a heat wave showed decreased reproduction and nutrient excretion after the heat-wave, indicating the potential for ecologically relevant delayed effects. Our study indicates that the immediate and delayed effects of stressors on individual organisms may directly and indirectly impact multiple ecosystem functions. In particular, delayed effects of environmental stress on individual consumers may cumulatively impede recovery due to decreased functioning following a perturbation. Reconciling these results with studies incorporating responses at higher levels of biological complexity will enhance our ability to forecast how individual responses upscale to ecosystem multifunctionality.
Data from: Behavioral changes in tadpoles after multigenerational exposure to an invasive intraguild predator
Prey subject to intraguild predation may face conflicting selective pressure on behavior, with competition favoring increased activity and predation favoring activity reduction. To discover how this evolutionary conflict might be resolved, we compared the behavior of tadpoles from four families drawn from different populations that had potentially co-evolved with an introduced intraguild predator for up to 90 years with the behavior of tadpoles from four families from unexposed populations. Intraguild prey were tadpoles of the declining California Red-legged Frog (Rana draytonii) and the intraguild predator was the invasive American Bullfrog (Lithobates catesbeianus), a voracious predator and strong competitor of other anurans. Limited evidence suggests that some native amphibians that have co-occurred with invasive predators for generations show adaptive behavioral responses to predator chemical cues. We tested whether R. draytonii larvae from families either allotopic or syntopic with bullfrogs would show responses to cues from overwintered bullfrog larvae. In the presence of cues, early-stage syntopic larvae decreased movement, consistent with an evolved innate defense, while allotopic larvae did not show behavioral changes. Later-stage syntopic larvae were generally more active than allotopic larvae, especially in the absence of cues, indicating a potential adaptive response to competition from bullfrog larvae. Increased activity appeared to be timed for when tadpoles became more resistant to predation. This is the first study to show changes in behavior across development consistent with complex selective pressure from an introduced intraguild predator. These findings have important implications for management of an endangered amphibian and a widely-introduced, invasive intraguild predator.
Data from: Changes in predator exposure, but not diet induce phenotypic plasticity in scorpion venom
Animals embedded between trophic levels must simultaneously balance pressures to deter predators and acquire resources. Venomous animals may use venom toxins to mediate both pressures, and thus changes in this balance may alter the composition of venoms. Basic theory suggests that greater exposure to a predator should induce a larger proportion of defensive venom components relative to offensive venom components, while increases in arms races with prey will elicit the reverse. Alternatively, reducing the need for venom expenditure for food acquisition, for example because of an increase in scavenging, may reduce the production of offensive venom components. Here, we investigated changes in scorpion venom composition using a mesocosm experiment where we manipulated scorpions' exposure to a surrogate vertebrate predator and live and dead prey. After six weeks, scorpions exposed to surrogate predators exhibited significantly different venom chemistry compared with naive scorpions. This change included a relative increase in some compounds toxic to vertebrate cells and a relative decrease in some compounds effective against their invertebrate prey. Our findings provide, to our knowledge, the first evidence for adaptive plasticity in venom composition. These changes in venom composition may increase the stability of food webs involving venomous animals.
Data from: Effects of neonicotinoid insecticide exposure and monofloral diet on nest-founding bumblebee queens
Bumblebees are among the world's most important groups of pollinating insects in natural and agricultural ecosystems. Each spring, queen bumblebees emerge from overwintering and initiate new nests, which ultimately give rise to workers and new reproductives later in the season. Nest initiation and survival are thus key drivers of both bumblebee pollination services and population dynamics. We performed the first laboratory experiment with the model bumblebee species Bombus impatiens that explores how early nesting success is impacted by the effects of temporary or more sustained exposure to sublethal levels of a neonicotinoid-type insecticide (imidacloprid at 5 ppb in nectar) and by reliance on a monofloral pollen diet, two factors that have been previously implicated in bumblebee decline. We found that queens exhibited increased mortality and dramatically reduced activity levels when exposed to imidacloprid, as well as delayed nest initiation and lower brood numbers in the nest, but partially recovered from these effects when they only received early, temporary exposure. The effects of pollen diet on individual queen- and colony-level responses were overshadowed by effects of the insecticide, although a monofloral pollen diet alone was sufficient to negatively impact brood production. These findings speak to the sensitivity of queen bumblebees during the nest initiation phase of the colony cycle, with implications for how queens and their young nests are uniquely impacted by exposure to threats such as pesticide exposure and foraging habitat unsuitability.
Data from: Distinguishing between reservoir exposure and human-to-human transmission for emerging pathogens using case onset data
Pathogens such as MERS-CoV, influenza A/H5N1 and influenza A/H7N9 are currently generating sporadic clusters of spillover human cases from animal reservoirs. The lack of a clear human epidemic suggests that the basic reproductive number R0 is below or very close to one for all three infections. However, robust cluster-based estimates for low R0 values are still desirable so as to help prioritise scarce resources between different emerging infections and to detect significant changes between clusters and over time. We developed an inferential transmission model capable of distinguishing the signal of human-to-human transmission from the background noise of direct spillover transmission (e.g. from markets or farms). By simulation, we showed that our approach could obtain unbiased estimates of R0, even when the temporal trend in spillover exposure was not fully known, so long as the serial interval of the infection and the timing of a sudden drop in spillover exposure were known (e.g. day of market closure). Applying our method to data from the three largest outbreaks of influenza A/H7N9 outbreak in China in 2013, we found evidence that human-to-human transmission accounted for 13% (95% credible interval 1%–32%) of cases overall. We estimated R0 for the three clusters to be: 0.19 in Shanghai (0.01-0.49), 0.29 in Jiangsu (0.03-0.73); and 0.03 in Zhejiang (0.00-0.22). If a reliable temporal trend for the spillover hazard could be estimated, for example by implementing widespread routine sampling in sentinel markets, it should be possible to estimate sub-critical values of R0 even more accurately. Should a similar strain emerge with R0>1, these methods could give a real-time indication that sustained transmission is occurring with well-characterised uncertainty.
Data from: Exposure to parasites increases promiscuity in a freshwater snail
Under the Red Queen hypothesis, outcrossing can produce genetically variable progeny, which may be more resistant, on average, to locally adapted parasites. Mating with multiple partners may enhance this resistance by further increasing the genetic variation among offspring. We exposed Potamopyrgus antipodarum to the eggs of a sterilising, trematode parasite and tested whether this altered mating behaviour. We found that exposure to parasites increased the number of snail mating pairs and the total number of different mating partners for both males and females. Thus our results suggest that, in host populations under parasite-mediated selection, exposure to infective propagules increases the rate of mating and the number of mates.
Data from: The nature and distribution of affiliative behaviour during exposure to mild threat
Individual reactions to danger in humans are often characterized as antisocial and self-preservative. Yet, more than fifty years of research have showed that humans often seek social partners and behave pro-socially when confronted by danger.Yet, more than fifty years of research have showed that humans seek social partners and behave pro-socially when confronted by danger. This research has relied on post-hoc verbal reports, which fall short of capturing the more spontaneous reactions to danger and determine their social nature. Real-world responses to danger are difficult to observe, due to their evanescent nature. Here, we took advantage of a series of photographs freely accessible online and provided by a haunted house attraction, which enabled us to examine the more immediate reactions to mild threat. Regarding the nature and structure of affiliative behaviour and their motivational correlates, we were able to analyse the distribution of gripping, a behaviour that could either be linked to self- or other-oriented protection. We found that gripping, an affiliative behaviour, was common, suggestive of the social nature of human immediate reactions to danger. We also found that, while gripping behaviour is quite stable across group sizes, mutual gripping dropped dramatically as group size increases. The fact that mutual gripping disappears when the number of available partners increases suggests that gripping behaviour most probably reflects a self-preservative motivation. We also found age class differences, with younger individuals showing more gripping but receiving little reciprocation. Also, the most exposed individuals received little mutual gripping. Altogether, these results suggest that primary reactions to threat in humans are driven by affiliative tendencies serving self-preservative motives.
Data from: Interactions between host sex and age of exposure modify the virulence-transmission trade-off
The patterns of immunity conferred by host sex or age represent two sources of host heterogeneity that can potentially shape the evolutionary trajectory of disease. With each host sex or age encountered, a pathogen's optimal exploitative strategy may change, leading to considerable variation in expression of pathogen transmission and virulence. To date, these host characteristics have been studied in the context of host fitness alone, overlooking the effects of host sex and age on the fundamental virulence-transmission trade-off faced by pathogens. Here we explicitly address the interaction of these characteristics and find that host sex and age at exposure to a pathogen affect age-specific patterns of mortality and the balance between pathogen transmission and virulence. When infecting age-structured male and female Daphnia magna with different genotypes of Pasteuria ramosa, we found that infection increased mortality rates across all age classes for females, whereas mortality only increased in the earliest age class for males. Female hosts allowed a variety of trade-offs between transmission and virulence to arise with each age and pathogen genotype. In contrast, this variation was dampened in males, with pathogens exhibiting declines in both virulence and transmission with increasing host age. Our results suggest that differences in exploitation potential of males and females to a pathogen can interact with host age to allow different virulence strategies to coexist, and illustrate the potential for these widespread sources of host heterogeneity to direct the evolution of disease in natural populations.
Sex‐differences in disease avoidance behavior vary across modes of pathogen exposure
<p>Sex‐differences in disease susceptibility are widespread, and these disparities are often compounded in cases where sexual dimorphism increases exposure risk to parasites for one sex more than the other. Studies rarely link sex‐differences in disease susceptibility to sex‐differences in infection avoidance behavior. Yet, understanding the intersection of hosts' susceptibility to infection and infection avoidance behavior is essential to predicting infection risk variation. Here, we use the fruit fly <i>Drosophila melanogaster</i> and a generalist entomopathogenic fungus, <i>Metarhizium robertsii</i>, which can be transmitted directly, indirectly, and post‐mortem as a model host–pathogen system. We test whether the relationship between susceptibility to infection and pathogen avoidance behavior covaries with host sex. We first measured differences in resistance between male and female flies after three different types of exposure—direct, sexual, and environmental—to infectious fungal conidiospores. Then, we tested whether male and female flies differed in the likelihood of mating with infected partners and their avoidance of food patches with increased infection risk. Females were more susceptible to infection under all three exposure techniques. When confronted with an infectious partner, females mated sooner than males. However, when given a choice between an exposed partner and an unexposed partner, females take longer to begin copulating compared with males, though neither sex was more likely to choose the unexposed partner than expected by chance. Neither male nor females flies avoided food patches containing infectious conidiospores, though only females show an aversion to food sites containing an infectious fly corpse. These experiments suggest that sex‐differences in disease susceptibility may be counteracted via differential pathogen avoidance behavior, though the strength of avoidance behavior appears to vary across different contexts of infection risk.</p>
Data from: Previous exposure to myxomatosis reduces survival of European rabbits during outbreaks of rabbit haemorrhagic disease
1. Exploiting disease and parasite synergies could increase the efficacy of biological control of invasive species. In Australia, two viruses were introduced to control European rabbits Oryctolagus cuniculus — myxoma virus in 1950, and rabbit haemorrhagic disease virus in 1995. While these biological controls caused initial declines of > 95% in affected populations, today rabbits remain a problem in many areas, despite recurring outbreaks of both diseases. 2. We used eighteen years of capture-mark-recapture, dead recovery, and antibody assay data from a sentinel population in South Australia to test whether these two diseases interact to modify the survival of individual wild rabbits. We compared four joint, multi-state, dead-recovery models to test the hypotheses that rabbit haemorrhagic disease and myxoma viruses have synergistic (i.e., previous exposure to one virus affects survival during outbreaks of the other virus) or additive effects (i.e., previous exposure to one virus does not affect survival during outbreaks of the other virus). 3. Rabbit haemorrhagic disease outbreaks reduced the survival of individuals with no immunity by more than half during the 58-day capture-trip intervals, i.e., from 0.86–0.90 to 0.37–0.48. Myxomatosis outbreaks had a smaller effect, reducing survival to 0.74– 0.82; however, myxomatosis outbreaks were more prolonged, spanning more than twice as many trips. 4. There was considerable information-theoretic support (wAICc = 0.69) for the model in which exposure to myxomatosis affected survival during rabbit haemorrhagic disease outbreaks. Rabbits previously exposed to myxoma virus had lower survival during rabbit haemorrhagic disease outbreaks than rabbits never exposed to either virus. There was negligible support for the model in which previous exposure to rabbit haemorrhagic disease affected survival in myxomatosis outbreaks (wAICc < 0.01). 5. Synthesis and applications — Our results indicate that biological control agents can have a greater impact than single-pathogen challenge studies might suggest. Introducing additional biological control agents might therefore increase mortality of rabbits beyond the additive effects of individual biological controls. Furthermore, our results show that by understanding and exploiting disease synergies, managers could increase the efficacy of biological controls for other invasive animals.
Data from: Costs and benefits of lifetime exposure to mating rivals in male Drosophila melanogaster
Theory predicts that males should evolve mechanisms to assess competition and allocate resources accordingly. This requires phenotypic plasticity, to accurately match responses to the environment. Plastic responses in males to sexual competition are diverse and widespread. However, our ability to understand and predict how they evolve is limited because their benefits are rarely measured, and costs are, as yet, entirely unquantified. In the fruit fly Drosophila melanogaster, males that anticipate strong competition for matings or fertilisations subsequently mate for longer and transfer more of two key seminal fluid proteins. This results in significantly elevated reproductive output. In this study we examined the fitness effects of male responses to rivals across the entire male lifespan. Males were exposed to rivals or not throughout life whilst controlling mating opportunities. Males showed significant responses to rivals throughout their lifetimes, associated with significant early-life fitness benefits. However, these disappeared after the third mating. There were also significant costs – males exposed to rivals took significantly fewer mating opportunities in later life and had significantly shorter lifespans than controls. The data suggest that there are substantial costs for males of mounting plastic responses to the threat of sexual competition.
Data from: Decrease in ribosomal RNA in Candida albicans induced by serum exposure
Candida albicans is an important polymorphic human pathogen. It can switch from a unicellular yeast form to germinating hypha, which may play a role in making it the successful pathogen it is. This hyphal transformation can be triggered by various extracellular stimuli, the most potent one being serum from any source. We have previously reported that Candida albicans transiently polyadenylates portions of both the large and small subunits of ribosomal RNA, shortly after serum exposure. Northern blots at the same time suggested that serum might induce a decrease in total ribosomal RNA. We have carried out a number of experiments to carefully assess this possibility and now report that serum significantly reduces ribosomal RNA in Candida albicans. Fluorometric measurements, Northern blotting and quantitative RT-PCR, have all confirmed this decrease. Timed experiments show that serum induces this decrease rapidly, as it was seen in as early as five minutes. Cell mass is not decreased as total cellular protein content remains the same and metabolic activity does not appear to slow, as assessed by XTT assay, and by the observation that cells form hyphal structures robustly. Another hyphal inducer, N-acetylglucosamine, also caused RNA decrease, but to a lesser extent. We also observed it in non-germinating yeast, such as Candida glabrata. The reason for this decrease is unknown and overall our data suggests that decrease in rRNA does not play a causal role in hyphal transformation. Rapid and significant decrease in a molecule so central to the yeast's biology is of some importance, and further studies, such as its effect on protein metabolism, will be required to better understand its purpose.
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.