On the reconceptualization of Alzheimer’s disease

In the hope of future treatments to prevent or slow down the disease, there is a strong movement towards an ever‐earlier detection of Alzheimer’s disease (AD). In conjunction with scientific developments, this has prompted a reconceptualization of AD, as a slowly progressive pathological process with a long asymptomatic phase. New concepts such as ‘preclinical’ and ‘prodromal’ AD have been introduced, raising a number of conceptual and ethical questions. We evaluate whether these new concepts are theoretically defensible, in light of theories of health and disease, and whether they should be understood as disease or as an at‐risk state. We introduce a pragmatic view on disease concepts and argue that an evaluation of the reconceptualization of AD should also take its aims and effects into account, and assess their ethical acceptability. The reconceptualization of AD is useful to coordinate research into preventive strategies, and may potentially benefit future patients. However, in the short term, early detection and labelling of ‘preclinical AD’ can potentially harm people. Since there is no treatment available and the predictive value is unclear, it may only create a group of ‘patients‐in‐waiting’ who may suffer from anxiety, uncertainty and stigmatization, but will never actually develop dementia. We conclude that only if the promise of preventive medication materializes, will the reconceptualization of AD turn out unequivocally to be for the better. Otherwise, the reconceptualization may do more harm than good.     

Ecological processes: A key element in strategies for nature conservation

Summary A common approach to nature conservation is to identify and protect natural ‘assets’ such as ecosystems and threatened species. While such actions are essential, protection of assets will not be effective unless the ecological processes that sustain them are maintained. Here, we consider the role of ecological processes and the complementary perspective for conservation arising from an emphasis on process. Many kinds of ecological processes sustain biodiversity: including climatic processes, primary productivity, hydrological processes, formation of biophysical habitats, interactions between species, movements of organisms and natural disturbance regimes. Anthropogenic threats to conservation exert their influence by modifying or disrupting these processes. Such threats extend across tenures, they frequently occur offsite, they commonly induce non‐linear responses, changes may be irreversible and the full consequences may not be experienced for lengthy periods. While many managers acknowledge these considerations in principle, there is much scope for greater recognition of ecological processes in nature conservation and greater emphasis on long time‐frames and large spatial scales in conservation planning. Practical measures that promote ecological processes include: monitoring to determine the trajectory and rate of processes; incorporating surrogates for processes in conservation and restoration projects; specific interventions to manipulate and restore processes; and planning for the ecological future before options are foreclosed. The long‐term conservation of biodiversity and the well‐being of human society depend upon both the protection of natural assets and maintaining the integrity of the ecological processes that sustain them.     

Emplacement and Displacement: Perceiving the Landscape Through Aboriginal Australian Acrylic Painting

Aboriginal Australian acrylic paintings have long been considered representations of mythologically invested landscape. This understanding has been made problematic by recent writings on ‘dwelling’. As common usage of the term ‘landscape’ seems to prioritize vision, to suggest that the acrylic paintings are landscapes only strengthens the suspicion that they are artifacts of displacement or distancing, rather than examples of the emplacement emphasized in this ‘dwelling perspective’. However, this paper will demonstrate that the relationship between acrylic painting and the land is more complex than such an interpretation. It will argue that the Aboriginal objectification of their relationship to the land is not inherently a distancing of the land.     

Opinion: Is gene mapping in wild populations useful for understanding and predicting adaptation to global change?

Changing environmental conditions will inevitably alter selection pressures. Over the long term, populations have to adapt to these altered conditions by evolutionary change to avoid extinction. Quantifying the ‘evolutionary potential’ of populations to predict whether they will be able to adapt fast enough to forecasted changes is crucial to fully assess the threat for biodiversity posed by climate change. Technological advances in sequencing and high‐throughput genotyping have now made genomic studies possible in a wide range of species. Such studies, in theory, allow an unprecedented understanding of the genomics of ecologically relevant traits and thereby a detailed assessment of the population's evolutionary potential. Aimed at a wider audience than only evolutionary geneticists, this paper gives an overview of how gene‐mapping studies have contributed to our understanding and prediction of evolutionary adaptations to climate change, identifies potential reasons why their contribution to understanding adaptation to climate change may remain limited, and highlights approaches to study and predict climate change adaptation that may be more promising, at least in the medium term.     

Short-term climatic trends affect the temporal variability of macroinvertebrates in California 'Mediterranean' streams

1. Long‐term studies in ecology are essential for understanding natural variability and in interpreting responses to disturbances and human perturbations. We assessed the long‐term variability, stability and persistence of macroinvertebrate communities by analysing data from three regions in northern California with a mediterranean‐climate. During the study period, precipitation either increased or decreased, and extreme drought events occurred in each region. 2. Temporal trends in precipitation resulted in shifts from ‘dry‐year’ communities, dominated by taxa adapted to no or low flow, to ‘wet‐year’ communities dominated by taxa adapted to high flows. The abundance of chironomid larvae was an important driver of community change. Directional change in community composition occurred at all sites and was correlated with precipitation patterns, with more dramatic change occurring in smaller streams. 3. All communities exhibited high to moderate persistence (defined by the presence/absence of a species) and moderate to low stability (defined by changes in abundance) over the study period. Stability and persistence were correlated with climatic variation (precipitation and El Niño Southern Oscillation) and stream size. Stability and persistence increased as a result of drought in small streams (first‐order) but decreased in larger streams (second‐ and third‐order). Communities from the dry season were less stable than those from the wet‐season. 4. This study demonstrates the importance of long‐term studies in capturing the effects of and recovery from rare events, such as the prolonged and extreme droughts considered here.     

The cumulative impact of annual coral bleaching can turn some coral species winners into losers

Mass coral bleaching events caused by elevated seawater temperatures result in extensive coral loss throughout the tropics, and are projected to increase in frequency and severity. If bleaching becomes an annual event later in this century, more than 90% of coral reefs worldwide may be at risk of long‐term degradation. While corals can recover from single isolated bleaching and can acclimate to recurring bleaching events that are separated by multiple years, it is currently unknown if and how they will survive and possibly acclimatize to annual coral bleaching. Here, we demonstrate for the first time that annual coral bleaching can dramatically alter thermal tolerance in Caribbean corals. We found that high coral energy reserves and changes in the dominant algal endosymbiont type (Symbiodinium spp.) facilitated rapid acclimation in Porites divaricata, whereas low energy reserves and a lack of algal phenotypic plasticity significantly increased susceptibility in Porites astreoides to bleaching the following year. Phenotypic plasticity in the dominant endosymbiont type of Orbicella faveolata did not prevent repeat bleaching, but may have facilitated rapid recovery. Thus, coral holobiont response to an isolated single bleaching event is not an accurate predictor of its response to bleaching the following year. Rather, the cumulative impact of annual coral bleaching can turn some coral species ‘winners’ into ‘losers’, and can also facilitate acclimation and turn some coral species ‘losers’ into ‘winners’. Overall, these findings indicate that cumulative impact of annual coral bleaching could result in some species becoming increasingly susceptible to bleaching and face a long‐term decline, while phenotypically plastic coral species will acclimatize and persist. Thus, annual coral bleaching and recovery could contribute to the selective loss of coral diversity as well as the overall decline of coral reefs in the Caribbean.     

WHAT PUTS THE ‘YUCK’ IN THE YUCK FACTOR?

The advances in biotechnology have given rise to a discussion concerning the strong emotional reaction expressed by the public towards biotechnological innovations. This reaction has been named the ‘Yuck‐factor’ by several theorists of bioethics. Leon Kass, the former chairman of the President's council on bioethics, has appraised this public reaction as ‘an emotional expression of deep wisdom, beyond reason's power fully to articulate it’. 1 Similar arguments have been forwarded by the Catholic Church, several Protestant denominations and the Pro‐Life movement. Several bioethicists have, however, opposed the idea of a disgust‐based morality. 2 Recent findings in cognitive science support the view that the strong negative emotions people often experience when faced with biotechnological ideas are not expressions of inner wisdom. The negative emotions may rather be the result of a cognitive violation the biotechnological innovations easily cause. Due to their evolutionary background, people have certain automatic and quick cognitive tendencies routinely used for categorizing and reasoning about nature, usually termed ‘folk biology’. Biotechnological processes like hybridisation and cloning clearly violate several of the cognitive rules people naturally apply for the explanation and categorization of their natural environment. As the cognitive tendencies routinely applied to the explanation of biological world are violated, an emotional response of fear, disgust and of something unnatural being underway is easily provoked. It is suggested in this paper that the reason behind the Yuck‐factor is not a deep inner wisdom, but a violation of natural human cognitive tendencies concerning the biological world.     

Creating inspiration: The role of the arts in creating empathy for ecological restoration

Summary Australia’s natural areas have long been a source of inspiration for artists. Some of this art is a response to the natural environment or represents it in some way, and some is exhibited or performed in the natural environment itself. The objectives of this article are to: investigate the relationship between art and the artists who create it and people who make a living in extension, landcare or on the land; and, develop an understanding of whether the arts can encourage an emotional affinity with the natural environment. Eighty‐nine key informant interviews were conducted in Australia, the UK, USA, Canada and Norway, including people working in the arts and people working in natural resources management. Those in the latter group were people who either (i) worked in an extension (outreach) or community facilitation capacity, or (ii) people who played a voluntary role with community on‐ground restoration projects or who showed exemplary behaviour towards the environment. All the people working in natural resources management cited examples of visual or performing arts that they had found inspiring, that encapsulated or defined their attitudes towards the natural environment, or which reinforced their attitudes towards the natural environment. From these interviews, the idea of ‘chains of inspiration’ emerged. Each of the ‘chains’ began with people who worked directly on the environment. These people were in turn influenced or inspired by particular art from which they gained an emotional affinity towards the environment. The chains then progressed to the artists who created the art. All of the chains ended up with the natural environment from which the artists drew their inspiration. The paper concludes that by providing an emotional affinity or empathy for the natural environment, art can have a major role in influencing pro‐environmental attitudes.     

Genuinely made up: camp,baroque, and other denaturalizing aesthetics in the cultural production of the real

The link that Jean‐Jacques Rousseau forged a long time ago between the ‘real’ and the ‘natural’ has proved to be indissoluble. Time and again, contemporary constructions of the real mobilize all that can be linked to nature. Inauthentic, by contrast, is that which is fabricated, made up, artificial, the all‐too‐evident result of human design. In Bahia, Brazil, the author encountered a completely different mode in the cultural production of the real. Analysing the performance of a Bahian drag queen who goes by the name of Gina da Mascar, the author discusses ‘camp’ and ‘baroque’ as registers that foster a sensibility for (and appreciation of) cultural forms that are ‘truly false’. He shows how the appeal of these registers – their persuasiveness, their form of truth‐telling – resonates with the sensibilities of people whose biographies are marked by radical discontinuities, and he argues that these registers might be understood as a popular articulation of the Lacanian understanding that symbolic closure is an impossibility.     

The ‘sparkle’ in fake eyes – the protective effect of mimic eyespots in lepidoptera

Many species of lepidoptera bear conspicuous circular patterns on their wings, known as eyespots, that are hypothesised to protect their bearers against predatory birds. In this study, we focus on a small but ubiquitous feature occurring naturally in lepidopteran eyespots, namely the so‐called ‘sparkle’. The ‘pupil’ in an eyespot is often highlighted by a ‘sparkle’, which is hypothesised to mimic a natural corneal total light reflection evident as a highlight, twinkle, or sparkle in the vertebrate eye. In a study exploring the presence of such sparkles, we found that 53% of lepidopteran eyespots exceeding 1 mm in diameter have a central, pinpoint‐like ‘sparkle’, 12% have a marginal, crescent‐shaped ‘sparkle’, 13% have a semi‐circular ‘sparkle’, and 22% have an intermediate semi‐circular to crescent‐shaped ‘sparkle’. In the lepidopterans’ natural resting position, the marginal ‘sparkles’ are positioned in the upper part of the eyespots’‘pupil’ and thus may create the illusion of a spherical eyeball. The ‘sparkles’ in lepidopteran eyespots do not only appear white to humans, but also reflect ultraviolet light. White and UV‐reflecting ‘sparkles’ also appear ‘white’ for UV‐sensitive viewers such as birds, and thus may effectively mimic the natural highlight in vertebrate eyes as an area of total light reflection. In field experiments using lepidopteran dummies baited with a mealworm, we show that the ‘sparkle’ is one of several components of eyespots eliciting a deterrent effect and that eyespots with a ‘sparkle’ in a natural position have a stronger deterrent effect than those with a ‘sparkle’ in an unnatural position. These findings support the eye mimicry hypothesis that better vertebrate eye mimicry improves the deterrent effect of eyespots.     

Paddock trees, parrots and agricultural production: An urgent need for large-scale, long-term restoration in south-eastern Australia

Summary Scattered trees, or ‘paddock trees’, are keystone structures, which provide multiple ecological values. However, they are in decline in many places. This has serious implications for species that use them, such as the vulnerable Superb Parrot (Polytelis swainsonii) of south‐eastern Australia. We outline three key aspects of the ecology, biology and distribution of the species that illustrate the implications of scattered tree decline. These are that (i) it depends on trees; (ii) it lives across agricultural landscapes; and (iii) it uses scattered tree landscapes dynamically in response to climate variation. We outline the dual challenge of maintaining populations of both scattered trees and the Superb Parrot over large scales and over the long term. Without urgent restoration action, a narrow bottleneck (where there are few mature trees) will make the long‐term future of the Superb Parrot precarious in these landscapes. We outline a vision for future landscapes that addresses this challenge, including the development of a form of Australian ‘wood‐pasture’. We suggest some ways that might be implemented at two scales. At the farm scale, we suggest (i) protecting what remnant vegetation we currently have; (ii) recruiting future large, old trees; (iii) sequentially setting aside land to ensure whole‐of‐farm tree regeneration; (iv) use of incentives to encourage restoration actions; and (v) using a revolving land fund to purchase and reorganize farms into economically and ecologically sustainable units. At the landscape scale, we suggest (i) the need for coordination of long‐term landscape restoration plans; (ii) the possible collaborative management of adjacent farms to ensure economic and ecological sustainability. We conclude that addressing the large‐scale and long‐term challenges of restoring scattered trees in landscapes occupied by the Superb Parrot could restore lost or diminished ecological services. This challenge illustrates the need for action at both the farm and the landscape scale that is planned over the short, medium and long term.     

Status and challenges for conservation of small mammal assemblages in South America

South America spans about 44° latitude, covers almost 18 million km², and is second only to Africa in continental mammal species richness. In spite of this richness, research on the status of this fauna and on the nature and magnitude of contemporary threats remains limited. Distilling threats to this diverse fauna at a continental scale is challenging, in part because of the limited availability of rigorous studies. Recognizing this constraint, we summarize key threats to small mammals in South America, emphasizing the roles of habitat loss and degradation, direct persecution, and the increasing threat of climate change. We focus on three regional ‘case studies’: the tropical Andes, Amazonia and adjacent lowland regions, and the southern temperate region. We close with a brief summary of recent findings at our long‐term research site in north‐central Chile as they pertain to projected threats to this fauna. Habitat alteration is a pervasive threat that has been magnified by market forces and globalization (e.g. extensive agricultural development in Amazonia), and threatens increasing numbers of populations and species. Climate change poses even greater threats, from changes in rainfall and runoff regimes and resulting changes in vegetative structure and composition to secondary influences on fire dynamics. It is likely that many changes have yet to be recognized, but existing threats suggest that the future may bring dramatic changes in the distribution of many mammal taxa, although it is not clear if key habitat elements (vegetation) will respond as rapidly as climatic factors, leading to substantial uncertainty. Climate change is likely to result in ‘winners’ and ‘losers’ but available information precludes detailed assessment of which species are likely to fall into which category. In the absence of long‐term monitoring and applied research to characterize these threats more accurately, and to develop strategies to reduce their impacts, managers already are being faced with daunting challenges. As the line between ‘pure’ and ‘applied’ research blurs in the face of converging interests of scientists and society we hope that solutions to these critical issues will be incorporated in addressing anticipated conservation crises.     

Long‐term temporal and spatial trends in eutrophication status of the Baltic Sea

Much of the Baltic Sea is currently classified as ‘affected by eutrophication’. The causes for this are twofold. First, current levels of nutrient inputs (nitrogen and phosphorus) from human activities exceed the natural processing capacity with an accumulation of nutrients in the Baltic Sea over the last 50–100 years. Secondly, the Baltic Sea is naturally susceptible to nutrient enrichment due to a combination of long retention times and stratification restricting ventilation of deep waters. Here, based on a unique data set collated from research activities and long‐term monitoring programs, we report on the temporal and spatial trends of eutrophication status for the open Baltic Sea over a 112‐year period using the HELCOM Eutrophication Assessment Tool (HEAT 3.0). Further, we analyse variation in the confidence of the eutrophication status assessment based on a systematic quantitative approach using coefficients of variation in the observations. The classifications in our assessment indicate that the first signs of eutrophication emerged in the mid‐1950s and the central parts of the Baltic Sea changed from being unaffected by eutrophication to being affected. We document improvements in eutrophication status that are direct consequences of long‐term efforts to reduce the inputs of nutrients. The reductions in both nitrogen and phosphorus loads have led to large‐scale alleviation of eutrophication and to a healthier Baltic Sea. Reduced confidence in our assessment is seen more recently due to reductions in the scope of monitoring programs. Our study sets a baseline for implementation of the ecosystem‐based management strategies and policies currently in place including the EU Marine Strategy Framework Directives and the HELCOM Baltic Sea Action Plan.     

Long‐term vegetation stability and the concept of potential natural vegetation in the Neotropics

When vegetation trends over time are analysed from an appropriate long‐term perspective using palaeoecological records, the concept of potential natural vegetation (PNV) is unsupported because of continual vegetation changes driven by natural or anthropic forcings. However, some palaeoecological records show long‐lasting (i.e. millennial) vegetation stability at multidecadal to centennial time scales in the absence of natural and human drivers of change, which fits within the definition of PNV. A more detailed palaeoecological analysis of these records shows that they are an exception rather than a rule, and that they cannot be differentiated from other transient ecological states. Therefore, long records of vegetation stability cannot be considered to be valid evidence for PNV. From a palaeoecological perspective, the PNV concept is concluded to be unnecessary, even in cases of multidecadal to centennial vegetation stability in the absence of environmental disturbance.     

Freshwater biodiversity: importance, threats, status and conservation challenges

Freshwater biodiversity is the over‐riding conservation priority during the International Decade for Action ‐‘Water for Life’ ‐ 2005 to 2015. Fresh water makes up only 0.01% of the World's water and approximately 0.8 % of the Earth's surface, yet this tiny fraction of global water supports at least 100 000 species out of approximately 1.8 million ‐ almost 6% of all described species. Inland waters and freshwater biodiversity constitute a valuable natural resource, in economic, cultural, aesthetic, scientific and educational terms. Their conservation and management are critical to the interests of all humans, nations and governments. Yet this precious heritage is in crisis. Fresh waters are experiencing declines in biodiversity far greater than those in the most affected terrestrial ecosystems, and if trends in human demands for water remain unaltered and species losses continue at current rates, the opportunity to conserve much of the remaining biodiversity in fresh water will vanish before the ‘Water for Life’ decade ends in 2015. Why is this so, and what is being done about it? This article explores the special features of freshwater habitats and the biodiversity they support that makes them especially vulnerable to human activities. We document threats to global freshwater biodiversity under five headings: overexploitation; water pollution; flow modification; destruction or degradation of habitat; and invasion by exotic species. Their combined and interacting influences have resulted in population declines and range reduction of freshwater biodiversity worldwide. Conservation of biodiversity is complicated by the landscape position of rivers and wetlands as ‘receivers’ of land‐use effluents, and the problems posed by endemism and thus non‐substitutability. In addition, in many parts of the world, fresh water is subject to severe competition among multiple human stakeholders. Protection of freshwater biodiversity is perhaps the ultimate conservation challenge because it is influenced by the upstream drainage network, the surrounding land, the riparian zone, and ‐ in the case of migrating aquatic fauna ‐ downstream reaches. Such prerequisites are hardly ever met. Immediate action is needed where opportunities exist to set aside intact lake and river ecosystems within large protected areas. For most of the global land surface, trade‐offs between conservation of freshwater biodiversity and human use of ecosystem goods and services are necessary. We advocate continuing attempts to check species loss but, in many situations, urge adoption of a compromise position of management for biodiversity conservation, ecosystem functioning and resilience, and human livelihoods in order to provide a viable long‐term basis for freshwater conservation. Recognition of this need will require adoption of a new paradigm for biodiversity protection and freshwater ecosystem management ‐ one that has been appropriately termed ‘reconciliation ecology’.     

Sex‐related variation in migration phenology in relation to sexual dimorphism: a test of competing hypotheses for the evolution of protandry

Timing of arrival/emergence to the breeding grounds is under contrasting natural and sexual selection pressures. Because of differences in sex roles and physiology, the balance between these pressures on either sex may differ, leading to earlier male (protandry) or female (protogyny) arrival. We test several competing hypotheses for the evolution of protandry using migration data for 22 bird species, including for the first time several monochromatic ones where sexual selection is supposedly less intense. Across species, protandry positively covaried with sexual size dimorphism but not with dichromatism. Within species, there was weak evidence that males migrate earlier because, being larger, they are less susceptible to adverse conditions. Our results do not support the ‘rank advantage’ and the ‘differential susceptibility’ hypotheses, nor the ‘mate opportunity’ hypothesis, which predicts covariation of protandry with dichromatism. Conversely, they are compatible with ‘mate choice’ arguments, whereby females use condition‐dependent arrival date to assess mate quality.     

Spatial scale resolves the niche versus neutral theory debate

The 50‐ha long‐term forest plot on Barro Colorado Island in Panama was ‘ground zero’ for the development of ecology's ‘neutral theory’ and comparisons with its ‘niche theory’ counterpart. In this issue, Garzon‐Lopez and colleagues used tree distributions at this site to recast the unresolved (and unresolvable) debate to show that observational scale drives the perception of which processes predominate.     

Drought and aquatic ecosystems: an introduction

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The ethics of biobanking: Assessing the right to control problem for broad consent

The biobank consent debate is one with deeply held convictions on both the ‘broad’ and ‘specific’ side with little sign of resolution. Recently, Thomas Ploug and Soren Holm have developed an alternative to both specific and broad consent: a meta‐consent framework. The aim here is to consider whether meta‐consent provides a ‘solution’ to the biobank consent debate. We clarify what ‘meta‐consent’ actually is (arguing that the label is a misnomer and ‘consent à la carte’ is more accurate). We identify problems with Ploug and Holm's arguments, and some challenges for meta‐consent. We focus on whether there is any ethical obligation to provide consent à la carte. There may seem to be so, especially if we draw upon an unclear appeal to the ethical significance of ‘respect for autonomy’. Similarly, there might seem to be an intuitive inference from the fact that ethically legitimate research requires informed consent to the conclusion that it thereby requires consent à la carte. It is shown that this line of inference is mistaken.