Climatic warming will likely have idiosyncratic impacts on infectious diseases, causing some to increase while others decrease or shift geographically. A mechanistic framework could better predict these different temperature-disease outcomes. However, such a remains challenging develop, due the nonlinear and (sometimes) opposing thermal responses of host parasite traits difficulty validating model predictions with observations experiments. We address challenges in zooplankton-fungus (Daphnia...

Abstract Community ecology can link habitat to disease via interactions among habitat, focal hosts, other their parasites, and predators. However, complicated food web (i.e., trophic predators impacts on host density diversity) often obscure the important pathways regulating disease. Here, we disentangle community drivers in a case study of planktonic disease, using two‐step approach. In step one, tested univariate field patterns linking directly two metrics. Density hosts (Daphnia dentifera...

The important hypothesis that organic livestock management reduces the prevalence of antimicrobial resistance is either fiercely supported or bitterly contested. Yet, empirical evidence supporting this view remains fragmentary, in part because relationships between use and drug vary dramatically across contexts, hosts, pathogens, country-specific regulations. Here, we synthesize global policies definitions 'organic' ask if farming results notable reductions when directly examined alongside...

Helminths infect humans, livestock, and wildlife, yet remain understudied despite their significant impact on public health agriculture. Because many of the most prevalent helminth-borne diseases are zoonotic, diverse host species closely interconnected. Therefore, understanding helminth transmission among wildlife could improve predictions management infection risks across species. A key challenge to dynamics in is accurately quantitatively tracking levels hosts environments. Traditional...

What drives the evolution of parasite life-history traits? Recent studies suggest that linking within- and between-host processes can provide key insight into both disease dynamics evolution. Still, it remains difficult to understand how pinpoint critical factors connecting these cross-scale feedbacks, particularly under non-equilibrium conditions; many natural host populations inherently fluctuate parasites themselves strongly alter stability populations. Here, we develop a general model...

Abstract Seasonal epidemics erupt commonly in nature and are driven by numerous mechanisms. Here, we suggest a new mechanism that could determine the size timing of seasonal epidemics: rearing environment changes performance parasites. This arises when environmental conditions which parasite is produced impact its performance—independently from current environment. To illustrate potential for “rearing effects”, show how temperature influences infection risk (transmission rate) Daphnia...

By altering the abundance, diversity, and distribution of species-and their pathogens-globalization may inadvertently select for more virulent pathogens. In Brazil's Atlantic Forest, a hotspot amphibian biodiversity, global trade has facilitated co-occurrence previously isolated enzootic panzootic lineages pathogenic amphibian-chytrid (Batrachochytrium dendrobatidis, 'Bd') generated new recombinant genotypes ('hybrids'). Epidemiological data indicate that declines are most severe in hybrid...

As natural enemies, parasites can dramatically harm host populations, and even catalyze their decline. Thus, identifying factors that promote disease spread is paramount. Environmental drive epidemics by altering traits involved in spread. For example, nutrients (such as nitrogen phosphorus) stimulate reproduction of both hosts or alter rates transmission stimulating productivity nutrition food resources hosts. Here, we demonstrate nutrient-trait-epidemic connections between the greatly...

Why do natural populations vary in the frequency of sexual reproduction? Virulent parasites may help explain why sex is favored during disease epidemics. To illustrate, we show a higher males and sexually produced offspring facultative parthenogenetic host fungal In multi-year survey 32 lakes, (an index sex) was zooplankton hosts with larger A lake mesocosm experiment established causality: experimental epidemics relative to disease-free controls. One common explanation for such pattern...

Abstract Temporary but substantial reductions in voluntary food intake routinely accompany parasite infection hosts ranging from insects to humans. This “parasite-mediated anorexia” drives dynamic nutrient-dependent feedbacks within and among hosts, which should alter the fitness of both parasites. Yet, few studies have examined evolutionary epidemiological consequences this ubiquitous overlooked component infection. Moreover, numerous biomedical, veterinary, farming practices (e.g., rapid...

Should parasites stabilize or destabilize consumer-resource dynamics? Recent theory suggests that parasite-enhanced mortality may confer underappreciated stability to their hosts. We tested this hypothesis using disease in zooplankton. Across both natural and experimental epidemics, bigger epidemics correlated with larger--not smaller--host fluctuations. Thus, we two mechanistic hypotheses explain destabilization apparent by parasites. First, enrichment could, principle, simultaneously...

Traditional epidemiological models assume that transmission increases proportionally to the density of parasites. However, empirical data frequently contradict this assumption. General yet mechanistic can explain why depends nonlinearly on parasite and thereby identify potential defensive strategies hosts. For example, hosts could decrease their exposure rates at higher densities (via behavioural avoidance) or per-parasite susceptibility when encountering more parasites (e.g. via stronger...

Abstract Food ingestion is one of the most basic features all organisms. However, obtaining precise—and high‐throughput—estimates feeding rates remains challenging, particularly for small, aquatic herbivores such as zooplankton, snails, and tadpoles. These animals typically consume low volumes food that are time‐consuming to accurately measure. We extend a standard high‐throughput fluorometry technique, which uses microplate reader 96‐well plates, practical tool studies in ecology,...

Virulent parasites can depress the densities of their hosts. Taxa that reduce disease via dilution effects might alleviate this burden. However, ‘diluter’ taxa also host through competition for shared resources. The combination and interspecific could even drive hosts extinct. Then again, genetically variable populations evolve in response to both competitors parasites. Can rapid evolution rescue density from harm caused by these ecological enemies? How such influence or size epidemics? In a...

Abstract Analyses of transient dynamics are critical to understanding infectious disease transmission and persistence. Identifying predicting transients across scales, from within-host community-level patterns, plays an important role in combating ongoing epidemics mitigating the risk future outbreaks. Moreover, greater emphases on non-asymptotic processes will enable timely evaluations wildlife human diseases lead improved surveillance efforts, preventive responses, intervention strategies....

Why does the severity of parasite infection differ dramatically across habitats? This question remains challenging to answer because multiple correlated pathways drive disease. Here, we examined habitat-disease links through direct effects on parasites and indirect predators (zooplankton), host diversity key life stages hosts. We used a case study amphibian hosts chytrid fungus, Batrachochytrium dendrobatidis, in set permanent ephemeral alpine ponds. A field experiment showed that...

Abstract Predators can directly or indirectly shape food webs through a combination of consumptive and non‐consumptive effects. Yet, how these effects vary across natural populations their consequences for adjacent ecosystems remains poorly resolved. We examined links between terrestrial predators aquatic on locally abundant amphibian, the red‐eyed treefrog ( Agalychnis callidryas ), which has arboreal eggs (heavily predated by snakes wasps) larvae; embryos escape threats hatching at an...

Abstract Animals ranging from mosquitoes to humans often vary their feeding behavior when infected or merely exposed pathogens. These so‐called “sickness behaviors” are part of the innate immune response with many consequences, including avoiding orally transmitted Fully understanding role this ubiquitous in host defense and pathogen evolution requires a quantitative account its impact on fitness across environmentally relevant contexts. Here, we use zooplankton fungal as case study ask if...

ABSTRACT Various stewardship policies, regulations, and voluntary bans have focused on protecting antimicrobials by limiting their use in livestock. These efforts ignited management shifts ranging from largely nominal (e.g., drugs banned for as ‘growth promoters’ were reclassified ‘prophylactic’ drugs) to organic farming, which drastically reduces or eliminates of antimicrobials. Understanding how these farming practices influence the prevalence antimicrobial resistance livestock carries...

We examined population densities and structural microhabitat use by Anolis griseus A. trinitatis at eight sites on the leeward (western) coast of St. Vincent, West Indies. Estimates density based Schnabel method varied according to habitat complexity ranged 5,208/ha for (a higher estimate one site was not considered due conditions that compromised accuracy estimates) 27,923/ha trinitatis. Our highest both species (32,867/ha) yet recorded any a two-species Lesser Antillean island. For...

Mansonellosis is an undermapped insect-transmitted disease caused by filarial nematodes that are estimated to infect hundreds of millions people globally. Despite their prevalence, there many outstanding questions regarding the general biology and health impacts responsible parasites. Historical reports suggest Colombian Amazon endemic for mansonellosis may serve as ideal location pursue these in backdrop other emerging pathogens. We deployed molecular classical diagnostic approaches survey

A common assumption is that pathogens more readily destabilize their host populations, leading to an elevated risk of driving both the and pathogen extinction. This logic underlies many strategies in conservation biology pest disease management. Yet, interplay between population stability likely varies across contexts, depending on environment traits hosts pathogens. context-dependence may be particularly important natural consumer-host populations where size- stage-structured competition...