Conservationists are far from able to assist all species under threat, if only for lack of funding. This places a premium on priorities: how can we support the most species at the least cost? One way is to identify 'biodiversity hotspots' where exceptional concentrations of endemic species are undergoing exceptional loss of habitat. As many as 44% of all species of vascular plants and 35% of all species in four vertebrate groups are confined to 25 hotspots comprising only 1.4% of the land surface of the Earth. This opens the way for a 'silver bullet' strategy on the part of conservation planners, focusing on these hotspots in proportion to their share of the world's species at risk.

Biodiversity hotspots for conservation priorities

抗原变异可使得多种致病微生物易于逃避宿主免疫应答。表达在感染红细胞表面的恶性疟原虫红细胞表面蛋白1（PfPMP1）与感染红细胞、内皮细胞、树突状细胞以及胎盘的单个或多个受体作用，在黏附及免疫逃避中起关键的作用。每个单倍体基因组var基因家族编码约60种成员，通过启动转录不同的var基因变异体为抗原变异提供了分子基础。

疟原虫var基因转换速率变化导致抗原变异[英]／Paul H, Robert P, Christodoulou Z, et al//Proc Natl Acad Sci U S A

Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

The Theory of Island Biogeography

Land use has generally been considered a local environmental issue, but it is becoming a force of global importance. Worldwide changes to forests, farmlands, waterways, and air are being driven by the need to provide food, fiber, water, and shelter to more than six billion people. Global croplands, pastures, plantations, and urban areas have expanded in recent decades, accompanied by large increases in energy, water, and fertilizer consumption, along with considerable losses of biodiversity. Such changes in land use have enabled humans to appropriate an increasing share of the planet’s resources, but they also potentially undermine the capacity of ecosystems to sustain food production, maintain freshwater and forest resources, regulate climate and air quality, and ameliorate infectious diseases. We face the challenge of managing trade-offs between immediate human needs and maintaining the capacity of the biosphere to provide goods and services in the long term.

/pdf/global-consequences-of-land-use-map7a6ziel.pdf

Global Consequences of Land Use

世界経済・社会統計 = World development indicators

I remember the ﬁrst time I saw a Tasmanian devil. It musthave been about twenty years ago. I had ﬂown overnightfrom Tahiti to Sydney, the old slow route across the Paciﬁc,to attend the International Parasitological Congress inBrisbane. We had an eight-hour layover and decided tovisit the Taronga Zoo, a fantastic ﬁrst glimpse of many ofAustralian’s endemic marsupial mammals. The devil was ina small exhibit surrounded by a circular moat. You couldstand within twelve feet of him as he stood on a tree trunk,pugnacious, totally self conﬁdent, and formidable. He hadthe demeanor of a cross between James Cagney and ErrolFlynn, his fellow Tasmanian, who had grown up on a farmin Tasmania where his father kept caged devils and ulti-mately became the foundation professor of zoology at theUniversity of Tasmania. The son migrated to Hollywoodand global fame as one of Warner Brother’s ﬁrst moviestars (Owen and Pemberton, 2005). The sharp piercing eyesof the zoo devil seemed to see us all as a potential meal, andhis formidable forelimbs suggested he would not take longto eviscerate us and enjoy the spoils. This was the image theearly settlers of Van Dieman’s Land (Tasmania) had of thedevil, a ferocious and insatiable carnivore that presented aformidable challenge to their sheep ﬂocks. Subsequent re-search showed this image to be false; devils are morescavengers than hunters and they do a formidable jobremoving dead, rotting, and potentially diseased carcassesfrom the landscape. The nocturnal attacks on sheep ﬂocksthat the farmers blamed on devils were more likely causedby the feral dog population their predecessors had acci-dentally introduced to island.Devils appeared again with surreal prescience when Imade a subsequent trip to Australia to attend the annualWildlife Disease Association meeting in Cairns in 2005.There was now a direct ﬂight from Los Angeles to Sydney,fourteen hours of Syrah, Cabernet, movies about dogs thatplay basketball, and half-read books and magazines aboutan ill-conceived war. I emerged from a half-sleep to ﬁndmyself watching an Australian TV documentary aboutTasmanian devils starring Menna Jones, an Australianbiologist who spent months in the wilds of Tasmaniadocumenting the behavioral ecology of free-living devils.The documentary ended with the chilling revelation thatdevils seemed to be suffering from a new disease in thewild, a strange syndrome of horrendous facial tumors thatprogressed to cause the eventual death of the devil.When I made it to the meeting in Cairns there was awhole session and several break-out groups discussing theDevil Facial Tumor Disease (DFTD). We all wrestled withthis as a new concept, a totally novel and very bizarre typeof pathogen whose emergence seemed totally unpredict-able. ‘‘Hmmm, sounds a bit like ‘canine transmissiblevenereal tumour’ to me’’ suggested Frances Gulland overbeers one night. Frances is always several steps ahead of therest of us and this insight proved closer to the truth thanmost of the other wild guesses kicked around the bar thatevening. Several of us were deeply concerned about thelikely impact on the devils and what should be done to slowthe spread of the disease. The papers gathered in this special

Sympathy for the Devil

In the northeast United States, control of West Nile virus (WNV) vectors has been unfocused because of a lack of accurate knowledge about the roles different mosquitoes play in WNV transmission. We analyzed the risk posed by 10 species of mosquitoes for transmitting WNV to humans by using a novel risk-assessment measure that combines information on the abundance, infection prevalence, vector competence, and biting behavior of vectors. This analysis suggests that 2 species (Culex pipiens L. and Cx. restuans Theobald [Diptera: Cilicidae]) not previously considered important in transmitting WNV to humans may be responsible for up to 80% of human WNV infections in this region. This finding suggests that control efforts should be focused on these species which may reduce effects on nontarget wetland organisms. Our risk measure has broad applicability to other regions and diseases and can be adapted for use as a predictive tool of future human WNV infections.

West Nile Virus Risk Assessment and the Bridge

Age-stratified serosurvey data are often used to understand spatiotemporal trends in disease incidence and exposure through estimating the Force-of-Infection (FoI). Typically, median or mean FoI estimates are used as the response variable in predictive models, often overlooking the uncertainty in estimated FoI values when fitting models and evaluating their predictive ability. To assess how this uncertainty impact predictions, we compared three approaches with three levels of uncertainty integration. We propose a performance indicator to assess how predictions reflect initial uncertainty.In Colombia, 76 serosurveys (1980-2014) conducted at municipality level provided age-stratified Chagas disease prevalence data. The yearly FoI was estimated at the serosurvey level using a time-varying catalytic model. Environmental, demographic and entomological predictors were used to fit and predict the FoI at municipality level from 1980 to 2010 across Colombia.A stratified bootstrap method was used to fit the models without temporal autocorrelation at the serosurvey level. The predictive ability of each model was evaluated to select the best-fit models within urban, rural and (Amerindian) indigenous settings. Model averaging, with the 10 best-fit models identified, was used to generate predictions.Our analysis shows a risk of overconfidence in model predictions when median estimates of FoI alone are used to fit and evaluate models, failing to account for uncertainty in FoI estimates. Our proposed methodology fully propagates uncertainty in the estimated FoI onto the generated predictions, providing realistic assessments of both central tendency and current uncertainty surrounding exposure to Chagas disease. 

/pdf/spatiotemporal-variations-in-exposure-chagas-disease-in-sdw57xs6.pdf

Spatiotemporal variations in exposure: Chagas disease in Colombia as a case study

Predator control programmes are generally implemented in an attempt to increase prey population sizes. However, predator removal could prove harmful to prey populations that are regulated primarily by parasitic infections rather than by predation. We develop models for microparasitic and macroparasitic infection that specify the conditions where predator removal will (a) increase the incidence of parasitic infection, (b) reduce the number of healthy individuals in the prey population and (c) decrease the overall size of the prey population. In general, predator removal is more likely to be harmful when the parasite is highly virulent, macroparasites are highly aggregated in their prey, hosts are long-lived and the predators select infected prey.

/pdf/perspectives-keeping-the-herds-healthy-and-alert-2qgvz8onla.pdf

PERSPECTIVES Keeping the herds healthy and alert: implications of predator control for infectious disease

Raccoons are host to diverse gastrointestinal parasites, but little is known about the ecology of these parasites in terms of their interactions with each other during coinfections, their interactions with host physiology and environmental factors, and their impact on raccoon health and survival. As a first step, we investigated the patterns of parasite infection and their demographic distribution in an urban-suburban population of raccoons trapped in the summers and autumns of 2018 and 2019. We collected faecal samples, demographic data, morphometric measurements, and blood smears, and used GPS data to classify trapping location by land cover type. Faecal floats were performed to detect and quantify gastrointestinal nematode eggs and coccidia oocysts, and white blood cell differentials were performed on blood smears to characterise white blood cell distributions. Data were analysed cross-sectionally and, where possible, longitudinally, using generalised linear models. Overall, 62.6% of sampled raccoons were infected with gastrointestinal nematodes, and 82.2% were infected with gastrointestinal coccidia. We analysed predictors of infection status and faecal egg count for three different morphotypes of nematode—Baylisascaris, strongyle, and capillariid nematodes—and found that infection status and egg count varied with Year, Month, Age class, Land cover, and coinfection status, though the significance of these predictors varied between nematode types. Gastrointestinal coccidia prevalence varied with Year, Month, Age class, strongyle infection status, and capillariid infection status. Coccidia oocyst counts were lower in adults and in October, but higher in females and in raccoons trapped in areas with natural land cover; furthermore, coccidia oocysts were positively associated with capillariid faecal egg counts. We found no evidence that gastrointestinal parasites influenced raccoon body condition or overwinter mortality, and so conclude that raccoons, though harbouring diverse and abundant gastrointestinal parasites, may be relatively tolerant of these parasites. 

Andrew P. Dobson

Papers

Sympathy for the Devil

West Nile Virus Risk Assessment and the Bridge

Spatiotemporal variations in exposure: Chagas disease in Colombia as a case study

PERSPECTIVES Keeping the herds healthy and alert: implications of predator control for infectious disease

Demographic, environmental and physiological predictors of gastrointestinal parasites in urban raccoons