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John E. Losey

Bio: John E. Losey is an academic researcher from Cornell University. The author has contributed to research in topics: Coccinella septempunctata & Coccinella novemnotata. The author has an hindex of 28, co-authored 88 publications receiving 6159 citations. Previous affiliations of John E. Losey include University of Maryland, College Park & Kansas State University.


Papers
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Journal ArticleDOI
TL;DR: The annual value of these ecological services provided by insects to the United States is estimated to be at least $57 billion, an amount that justifies greater investment in the conservation of these services.
Abstract: In this article we focus on the vital ecological services provided by insects. We restrict our focus to services provided by “wild” insects; we do not include services from domesticated or mass-reared insect species. The four insect services for which we provide value estimates—dung burial, pest control, pollination, and wildlife nutrition—were chosen not because of their importance but because of the availability of data and an algorithm for their estimation. We base our estimations of the value of each service on projections of losses that would accrue if insects were not functioning at their current level. We estimate the annual value of these ecological services provided in the United States to be at least $57 billion, an amount that justifies greater investment in the conservation of these services.

1,573 citations

Journal ArticleDOI
20 May 1999-Nature
TL;DR: In a laboratory assay, it is found that larvae of the monarch butterfly, Danaus plexippus, reared on milkweed leaves dusted with pollen from Bt corn, ate less, grew more slowly and suffered higher mortality than larvae rearing on leaves dusting with untransformed corn pollen or on leaves without pollen.
Abstract: Although plants transformed with genetic material from the bacterium Bacillus thuringiensis (Bt ) are generally thought to have negligible impact on non-target organisms1, Bt corn plants might represent a risk because most hybrids express the Bt toxin in pollen2, and corn pollen is dispersed over at least 60 metres by wind3. Corn pollen is deposited on other plants near corn fields and can be ingested by the non-target organisms that consume these plants. In a laboratory assay we found that larvae of the monarch butterfly, Danaus plexippus, reared on milkweed leaves dusted with pollen from Bt corn, ate less, grew more slowly and suffered higher mortality than larvae reared on leaves dusted with untransformed corn pollen or on leaves without pollen.

1,148 citations

Journal ArticleDOI
01 Sep 1998-Ecology
TL;DR: The results indicate that the importance of ground-foraging predators in agroecosys- tems may need to be reevaluated and that positive interactions between predators must be considered in models predicting the impact of multiple predator complexes.
Abstract: Interactions among predators can a have substantial effect on the total impact of the predator complex. We investigated the interaction between foliar-foraging (Coccinella septempunctata) and ground-foraging (Harpalus pennsylvanicus) predators of the pea aphid (Acyrthosiphon pisum) in a series of laboratory and field experiments. The intensity and direction of the interaction were determined by comparing the combined and individual impacts of both predators. In a laboratory mesocosm, the combined predation rate of both predators was nearly double the sum of their individual predation rates. The mechanism for the interaction was the aphid "dropping" behavior elicited by C. septempunctata, which rendered the aphids susceptible to predation by H. pennsylvanicus on the ground. The strength of the synergistic interaction increased with increasing prey density. The interaction between the predators was also demonstrated in both open and closed field cages where the combined impact of the two predators on aphid population growth was significantly greater than the sum of their individual impacts. These results indicate that the importance of ground-foraging predators in agroecosys- tems may need to be reevaluated and that positive interactions between predators must be considered in models predicting the impact of multiple predator complexes.

518 citations

Journal ArticleDOI
TL;DR: An overview of the invasion history and ecology of H. axyridis globally with consideration of future research perspectives is provided.
Abstract: The harlequin ladybird, Harmonia axyridis (Pallas) (Coleoptera: Coccinellidae), is native to Asia but has been intentionally introduced to many countries as a biological control agent of pest insects. In numerous countries, however, it has been introduced unintentionally. The dramatic spread of H. axyridis within many countries has been met with considerable trepidation. It is a generalist top predator, able to thrive in many habitats and across wide climatic conditions. It poses a threat to biodiversity, particularly aphidophagous insects, through competition and predation, and in many countries adverse effects have been reported on other species, particularly coccinellids. However, the patterns are not consistent around the world and seem to be affected by many factors including landscape and climate. Research on H. axyridis has provided detailed insights into invasion biology from broad patterns and processes to approaches in surveillance and monitoring. An impressive number of studies on this alien species have provided mechanistic evidence alongside models explaining large-scale patterns and processes. The involvement of citizens in monitoring this species in a number of countries around the world is inspiring and has provided data on scales that would be otherwise unachievable. Harmonia axyridis has successfully been used as a model invasive alien species and has been the inspiration for global collaborations at various scales. There is considerable scope to expand the research and associated collaborations, particularly to increase the breadth of parallel studies conducted in the native and invaded regions. Indeed a qualitative comparison of biological traits across the native and invaded range suggests that there are differences which ultimately could influence the population dynamics of this invader. Here we provide an overview of the invasion history and ecology of H. axyridis globally with consideration of future research perspectives. We reflect broadly on the contributions of such research to our understanding of invasion biology while also informing policy and people.

264 citations

Journal ArticleDOI
TL;DR: In this paper, the authors used data derived from three coccinellid-focused citizen science programs to examine the costs and benefits of data collection from direct citizen-science (data used without verification) and verified citizen-scientism (observations verified by trained experts) programs.
Abstract: Citizen scientists have the potential to play a crucial role in the study of rapidly changing lady beetle (Coccinellidae) populations. We used data derived from three coccinellid-focused citizen-science programs to examine the costs and benefits of data collection from direct citizen-science (data used without verification) and verified citizen-science (observations verified by trained experts) programs. Data collated through direct citizen science overestimated species richness and diversity values in comparison to verified data, thereby influencing interpretation. The use of citizen scientists to collect data also influenced research costs; our analysis shows that verified citizen science was more cost effective than traditional science (in terms of data gathered per dollar). The ability to collect a greater number of samples through direct citizen science may compensate for reduced accuracy, depending on the type of data collected and the type(s) and extent of errors committed by volunteers.

257 citations


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01 Jan 2016
TL;DR: The modern applied statistics with s is universally compatible with any devices to read, and is available in the digital library an online access to it is set as public so you can download it instantly.
Abstract: Thank you very much for downloading modern applied statistics with s. As you may know, people have search hundreds times for their favorite readings like this modern applied statistics with s, but end up in harmful downloads. Rather than reading a good book with a cup of coffee in the afternoon, instead they cope with some harmful virus inside their laptop. modern applied statistics with s is available in our digital library an online access to it is set as public so you can download it instantly. Our digital library saves in multiple countries, allowing you to get the most less latency time to download any of our books like this one. Kindly say, the modern applied statistics with s is universally compatible with any devices to read.

5,249 citations

Journal ArticleDOI
TL;DR: The nature and extent of reported declines, and the potential drivers of pollinator loss are described, including habitat loss and fragmentation, agrochemicals, pathogens, alien species, climate change and the interactions between them are reviewed.
Abstract: Pollinators are a key component of global biodiversity, providing vital ecosystem services to crops and wild plants. There is clear evidence of recent declines in both wild and domesticated pollinators, and parallel declines in the plants that rely upon them. Here we describe the nature and extent of reported declines, and review the potential drivers of pollinator loss, including habitat loss and fragmentation, agrochemicals, pathogens, alien species, climate change and the interactions between them. Pollinator declines can result in loss of pollination services which have important negative ecological and economic impacts that could significantly affect the maintenance of wild plant diversity, wider ecosystem stability, crop production, food security and human welfare.

4,608 citations

Journal ArticleDOI
TL;DR: In this article, the negative and positive effects of agricultural land use for the conservation of biodiversity, and its relation to ecosystem services, need a landscape perspective, which is difficult to be found in the literature.
Abstract: Understanding the negative and positive effects of agricultural land use for the conservation of biodiversity, and its relation to ecosystem services, needs a landscape perspective. Agriculture can contribute to the conservation of high-diversity systems, which may provide important ecosystem services such as pollination and biological control via complementarity and sampling effects. Land-use management is often focused on few species and local processes, but in dynamic, agricultural landscapes, only a diversity of insurance species may guarantee resilience (the capacity to reorganize after disturbance). Interacting species experience their surrounding landscape at different spatial scales, which influences trophic interactions. Structurally complex landscapes enhance local diversity in agroecosystems, which may compensate for local high-intensity management. Organisms with high-dispersal abilities appear to drive these biodiversity patterns and ecosystem services, because of their recolonization ability and larger resources experienced. Agri-environment schemes (incentives for farmers to benefit the environment) need to broaden their perspective and to take the different responses to schemes in simple (high impact) and complex (low impact) agricultural landscapes into account. In simple landscapes, local allocation of habitat is more important than in complex landscapes, which are in total at risk. However, little knowledge of the relative importance of local and landscape management for biodiversity and its relation to ecosystem services make reliable recommendations difficult.

3,460 citations

01 Jan 2005
TL;DR: In this article, the negative and positive effects of agricultural land use for the conservation of biodiversity, and its relation to ecosystem services, need a landscape perspective, which may compensate for local highintensity management.
Abstract: Understanding the negative and positive effects of agricultural land use for the conservation of biodiversity, and its relation to ecosystem services, needs a landscape perspective. Agriculture can contribute to the conservation of high-diversity systems, which may provide important ecosystem services such as pollination and biological control via complementarity and sampling effects. Land-use management is often focused on few species and local processes, but in dynamic, agricultural landscapes, only a diversity of insurance species may guarantee resilience (the capacity to reorganize after disturbance). Interacting species experience their surrounding landscape at different spatial scales, which influences trophic interactions. Structurally complex landscapes enhance local diversity in agroecosystems, which may compensate for local highintensity management. Organisms with high-dispersal abilities appear to drive these biodiversity patterns and ecosystem services, because of their recolonization ability and larger resources experienced. Agri-environment schemes (incentives for farmers to benefit the environment) need to broaden their perspective and to take the different responses to schemes in simple (high impact) and complex (low impact) agricultural landscapes into account. In simple landscapes, local allocation of habitat is more important than in complex landscapes, which are in total at risk. However, little knowledge of the relative importance of local and landscape management for biodiversity and its relation to ecosystem services make reliable recommendations difficult.

3,387 citations

Journal ArticleDOI
25 Jul 2014-Science
TL;DR: Defaunation is both a pervasive component of the planet’s sixth mass extinction and also a major driver of global ecological change.
Abstract: We live amid a global wave of anthropogenically driven biodiversity loss: species and population extirpations and, critically, declines in local species abundance. Particularly, human impacts on animal biodiversity are an under-recognized form of global environmental change. Among terrestrial vertebrates, 322 species have become extinct since 1500, and populations of the remaining species show 25% average decline in abundance. Invertebrate patterns are equally dire: 67% of monitored populations show 45% mean abundance decline. Such animal declines will cascade onto ecosystem functioning and human well-being. Much remains unknown about this “Anthropocene defaunation”; these knowledge gaps hinder our capacity to predict and limit defaunation impacts. Clearly, however, defaunation is both a pervasive component of the planet’s sixth mass extinction and also a major driver of global ecological change.

2,697 citations