684 research outputs found
Adaptive female choice for middle-aged mates in a lekking sandfly
Most theoretical models of age-related mate choice predict that females should prefer older males because they have proven survival ability. An alternative view is that older males represent inferior mates because of negative genetic correlations between early and late fitness components, or because older males have traded off longevity against other fitness components, have accumulated deleterious germ-line mutations, or are less well adapted to current conditions than more recently born individuals. While numerous studies have reported female choice for older males, few have explicitly examined the fitness consequences of such a preference. We present evidence from a lekking sandfly, Lutzomyia longipalpis , showing that choosy females discriminate against older males and gain a fitness benefit from their choice. When permitted free choice from an aggregation consisting of males aged zero to two days (young), four to six days (middle-aged) and eight to ten days (old), females preferentially mated with middle-aged males, but all measures of female reproductive success were independent of male age. In contrast, when a second set of females was randomly assigned single virgin males of known age, the eggs of those paired to old mates exhibited lower hatching success than the eggs of females mated to young or middle-aged males. These results suggest that females avoid mating with older males because they represent poorer quality mates. Age-related differences in male quality may have a genetic basis, but could equally well arise through a phenotypic decline in sperm quality or sperm transfer ability with male age. The lack of evidence of female discrimination against older males from other studies may be because these did not explore the reproductive success of the full age range of males
COVID-19: Analogues and lessons for tackling the extinction and climate crises
As environmental scientists working in countries whose COVID-linked deaths already exceed their military casualties from all campaigns since 1945, we believe there are significant messages from the handling of this horrific disease for efforts addressing the enormous challenges posed by the ongoing extinction and climate emergencies
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Agriculture as a key element for conservation: Reasons for caution
This is the pre-peer reviewed version of the following article: Phalan B., Balmford A. & Green R. E. (2012) Agriculture as a key element for conservation: reasons for caution. Conservation Letters 5: 323–324 which has been published in final form at: http://onlinelibrary.wiley.com/doi/10.1111/j.1755-263X.2012.00248.x/abstrac
The ecomics of ecosystems and biodiversity: scoping the scale
The G8 decided in March 2007 to initiate a “Review on the economics of biodiversity loss”, in the so called Potsdam Initiative: 'In a global study we will initiate the process of analysing the global economic benefit of biological diversity, the costs of the loss of biodiversity and the failure to take protective measures versus the costs of effective conservation. The study is being supported by the European Commission (together with the European Environmental Agency and in cooperation with the German Government. “The objective of the current study is to provide a coherent overview of existing scientific knowledge upon which to base the economics of the Review, and to propose a coherent global programme of scientific work, both for Phase 2 (consolidation) and to enable more robust future iterations of the Review beyond 2010.
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The biodiversity intactness index may underestimate losses.
The Biodiversity Intactness Index (BII) is a high-profile metric of an area’s average abundance of wild species relative to that in pre-modern times1 or in primary vegetation under current climatic conditions2. It has been endorsed by the Group on Earth Observations of the Biodiversity Observation Network, adopted by the Intergovernmental Platform on Biodiversity and Ecosystem Services as a "core" indicator of progress towards the Convention on Biological Diversity’s Aichi targets 12 and 14, and accepted by the Biodiversity Indicators Partnership as an indicator for Aichi target 5. We strongly support development of spatially-explicit indicators such as the BII, which can be used to prioritise areas for conservation interventions. However, it is important that the metric is as robust as possible, and we have noticed several unusual features of the BII that concern us
Conserving nature out of fear or knowledge? Using threatening versus connecting messages to generate support for environmental causes
Threatening and connecting messages are two types of appeals commonly used to encourage conservation behaviors, yet little research has examined their psychological impacts and behavioral outcomes. This paper describes two studies contrasting these approaches with a neutral comparison and testing their effects on state levels of negative affect, caring, and openness, psychological states which we expected in turn would encourage conservation behavior. Participants viewed visually identical nature videos with no text, connecting text or negative text. They then reported on their state experiences, and were asked to engage in conservation behaviors, including supporting conservation organizations. Findings showed that connecting messages increased caring and openness, and decreased negative affect, and by doing so elicited more conservation behaviors. On the other hand, threatening messages showed no beneficial effects above a neutral comparison without an appeal. Our findings, which we contextualize in motivational theory, can be used to inform the use of messages to promote conservation.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.jnc.2015.04.00
The worldwide costs of marine protected areas
Declines in marine harvests, wildlife, and habitats have prompted calls at both the 2002 World Summit on Sustainable Development and the 2003 World Parks Congress for the establishment of a global system of marine protected areas (MPAs). MPAs that restrict fishing and other human activities conserve habitats and populations and, by exporting biomass, may sustain or increase yields of nearby fisheries. Here we provide an estimate of the costs of a global MPA network, based on a survey of the running costs of 83 MPAs worldwide. Annual running costs per unit area spanned six orders of magnitude, and were higher in MPAs that were smaller, closer to coasts, and in high-cost, developed countries. Models extrapolating these findings suggest that a global MPA network meeting the World Parks Congress target of conserving 20–30% of the world’s seas might cost between 19 billion annually to run and would probably create around one million jobs. Although substantial, gross network costs are less than current government expenditures on harmful subsidies to industrial fisheries. They also ignore potential private gains from improved fisheries and tourism and are dwarfed by likely social gains from increasing the sustainability of fisheries and securing vital ecosystem services
Parks and Tourism
To protect biodiversity, parks agencies need political and financial support. Recreational visitors can bring both, but commercial tourism carries risks
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Nature and Community Cohesion
Individuals may be losing touch with nature as their contact with it decreases worldwide. While the consequences for people’s personal well-being outcomes are becoming well documented, there is almost no research examining the social correlates of contact with nature. This paper used a large nationally representative sample to link objective (% greenspace) and subjective measurements of contact with nature, community cohesion, and local crime incidence. The perceived quality, views, and amount of time spent in nature were linked to more community cohesion, and in turn the perception of cohesive communities enhances individual well-being outcomes and contributions back to society through higher workplace productivity and environmentally responsible behaviors. Findings also indicated that local nature was linked to lower crime both directly and indirectly through its effects on community cohesion.This research was funded in part by the ESRC (project number RES-064-27-0019).This is the author accepted manuscript. The final version is available from Oxford University Press via http://dx.doi.org/10.1093/biosci/biv15
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Impact of increasing vegetarian availability on meal selection and sales in cafeterias.
Shifting people in higher income countries toward more plant-based diets would protect the natural environment and improve population health. Research in other domains suggests altering the physical environments in which people make decisions ("nudging") holds promise for achieving socially desirable behavior change. Here, we examine the impact of attempting to nudge meal selection by increasing the proportion of vegetarian meals offered in a year-long large-scale series of observational and experimental field studies. Anonymized individual-level data from 94,644 meals purchased in 2017 were collected from 3 cafeterias at an English university. Doubling the proportion of vegetarian meals available from 25 to 50% (e.g., from 1 in 4 to 2 in 4 options) increased vegetarian meal sales (and decreased meat meal sales) by 14.9 and 14.5 percentage points in the observational study (2 cafeterias) and by 7.8 percentage points in the experimental study (1 cafeteria), equivalent to proportional increases in vegetarian meal sales of 61.8%, 78.8%, and 40.8%, respectively. Linking sales data to participants' previous meal purchases revealed that the largest effects were found in the quartile of diners with the lowest prior levels of vegetarian meal selection. Moreover, serving more vegetarian options had little impact on overall sales and did not lead to detectable rebound effects: Vegetarian sales were not lower at other mealtimes. These results provide robust evidence to support the potential for simple changes to catering practices to make an important contribution to achieving more sustainable diets at the population level.NERC scolarshi
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