How the diversity of human concepts of nature affects conservation of biodiversity.

Protecting nature has become a global concern. However, the very idea of nature is problematic. We examined the etymological and semantic diversity of the word used to translate nature in a conservation context in 76 of the primary languages of the world to identify the different relationships between humankind and nature. Surprisingly, the number of morphemes (distinct etymological roots) used by 7 billion people was low. Different linguistic superfamilies shared the same etymon across large cultural areas that correlate with the distribution of major religions. However, we found large differences in etymological meanings among these words, echoing the semantic differences and historical ambiguity of the contemporary European concept of nature. The principal current Western meaning of nature in environmental public policy, conservation science, and environmental ethics-that which is not a human artifact-appears to be relatively rare and recent and to contradict the vision of nature in most other cultures, including those of pre-Christian Europe. To avoid implicit cultural bias and hegemony-and thus to be globally intelligible and effective-it behooves nature conservationists to take into account this semantic diversity when proposing conservation policies and implementing conservation practices.

Cómo Afecta la Diversidad de los Conceptos Humanos de la Naturaleza a la Conservación de la Biodiversidad Resumen La protección de la naturaleza se ha vuelto una preocupación a nivel mundial; sin embargo, la misma idea de naturaleza es problemática. Examinamos la diversidad etimológica y semántica de la palabra que se utiliza para traducir la palabra nature en un contexto de conservación en los 76 lenguajes primarios del mundo y así identificar las diferentes relaciones entre la humanidad y la naturaleza. Sorprendentemente, el número de morfemas (raíces etimológicas distintas) usado por siete mil millones de personas fue bajo. Las diferentes superfamilias lingüísticas compartieron etimologías a lo largo de grandes áreas culturales que se correlacionan con la distribución de las religiones más importantes. Sin embargo, encontramos diferencias importantes en los significados etimológicos entre estas palabras, reflejando las diferencias semánticas y la ambigüedad histórica del concepto europeo contemporáneo de naturaleza. El principal significado occidental actual de nature dentro de la política ambiental pública, las ciencias de la conservación y la ética ambiental - aquello que no es un artefacto humano - parece ser relativamente raro y reciente, además de que contradice la visión de la naturaleza que tienen la mayoría de las demás culturas, incluyendo a aquellas de la Europa precristiana. Para evitar el sesgo y la hegemonía cultural que vienen implícitos - y así ser mundialmente entendibles y efectivos - le conviene a los conservacionistas de la naturaleza que consideren esta diversidad semántica cuando propongan políticas de conservación e implementen las prácticas de conservación.

Four priorities for new links between conservation science and accounting research.

Article impact statement: New collaborations with accounting research can improve conservation impact of ecosystem-based information systems.

Relative importance of the land-use composition and intensity for the bird community composition in anthropogenic landscapes.

Humans are changing the biosphere by exerting pressure on land via different land uses with variable intensities. Quantifying the relative importance of the land-use composition and intensity for communities may provide valuable insights for understanding community dynamics in human-dominated landscapes. Here, we evaluate the relative importance of the land-use composition versus land-use intensity on the bird community structure in the highly human-dominated region surrounding Paris, France. The land-use composition was calculated from a land cover map, whereas the land-use intensity (reverse intensity) was represented by the primary productivity remaining after human appropriation (NPP remaining), which was estimated using remote sensing imagery. We used variance partitioning to evaluate the relative importance of the land-use composition versus intensity for explaining bird community species richness, total abundance, trophic levels, and habitat specialization in urban, farmland, and woodland habitats. The land-use composition and intensity affected specialization and richness more than trophic levels and abundance. The importance of the land-use intensity was slightly higher than that of the composition for richness, specialization, and trophic levels in farmland and urban areas, while the land-use composition was a stronger predictor of abundance. The intensity contributed more to the community indices in anthropogenic habitats (farmland and urban areas) than to those in woodlands. Richness, trophic levels, and specialization in woodlands tended to increase with the NPP remaining value. The heterogeneity of land uses and intensity levels in the landscape consistently promoted species richness but reduced habitat specialization and trophic levels. This study demonstrates the complementarity of NPP remaining to the land-use composition for understanding community structure in anthropogenic landscapes. Our results show, for the first time, that the productivity remaining after human appropriation is a determinant driver of animal community patterns, independent of the type of land use.

Fixism and conservation science.

The field of biodiversity conservation has recently been criticized as relying on a fixist view of the living world in which existing species constitute at the same time targets of conservation efforts and static states of reference, which is in apparent disagreement with evolutionary dynamics. We reviewed the prominent role of species as conservation units and the common benchmark approach to conservation that aims to use past biodiversity as a reference to conserve current biodiversity. We found that the species approach is justified by the discrepancy between the time scales of macroevolution and human influence and that biodiversity benchmarks are based on reference processes rather than fixed reference states. Overall, we argue that the ethical and theoretical frameworks underlying conservation research are based on macroevolutionary processes, such as extinction dynamics. Current species, phylogenetic, community, and functional conservation approaches constitute short-term responses to short-term human effects on these reference processes, and these approaches are consistent with evolutionary principles.

Offsets and conservation of the species of the EU habitats and birds directives.

Biodiversity offsets are intended to achieve no net loss of biodiversity due to economic and human development. A variety of biodiversity components are addressed by offset policies. It is required that loss of protected species due to development be offset under the EU Habitats and Birds Directives in Europe. We call this type of offset a species-equality offset because the offset pertains to the same species affected by the development project. Whether species equality can be achieved by offset design is unknown. We addressed this gap by reviewing derogation files (i.e., specific files that describe mitigation measures to ensure no net loss under the EU Habitats and Birds Directives) from 85 development projects in France (2009-2010). We collected information on type of effect (reversible vs. irreversible) and characteristics of affected and offset sites (i.e., types of species, total area). We analyzed how the type of effect and the affected-site characteristics influenced the occurrence of offset measures. The proportion of species targeted by offset measures (i.e., offset species) increased with the irreversibility of the effect of development and the conservation status of the species affected by development (i.e., affected species). Not all effects on endangered species (International Union for Conservation of Nature Red List) were offset; on average, 82% of affected species would be offset. Twenty-six percent of species of least concern were offset species. Thirty-five percent of development projects considered all affected species in their offset measures. Species richness was much lower in offset sites than in developed sites even after offset proposals. For developed areas where species richness was relatively high before development, species richness at offset sites was 5-10 times lower. The species-equality principle appears to have been applied only partially in offset policies, as in the EU directives. We suggest the application of this principle through offsets is highly important for the long-term conservation of biodiversity in Europe. Compensaciones y Conservación de las Especies de las Directivas de Hábitats y Aves de la UE.

Scientific contributions of extensive biodiversity monitoring.

To develop a complete and informative biodiversity observation system, it is necessary to compare the strengths and limits of various monitoring schemes. In this article, we examine the various advantages of extensively monitoring fine-grained spatial variations of biodiversity, where the prominent traits of many species within a community (abundance, phenology, etc.) are regularly recorded at numerous sites over a large territory, usually via human observation networks. Linking these variations with environmental factors sheds lights on the major mechanisms leading to changes in biodiversity, thus increasing our knowledge of macroecology and community ecology. This extensive monitoring allows us to assess diffuse effects, contributing to the sound use of the precautionary principle. Combined with site-focused monitoring, information gathered from extensive monitoring provides the raw material necessary to build biodiversity scenarios.

An indicator of the impact of climatic change on European bird populations.

Rapid climatic change poses a threat to global biodiversity. There is extensive evidence that recent climatic change has affected animal and plant populations, but no indicators exist that summarise impacts over many species and large areas. We use data on long-term population trends of European birds to develop such an indicator. We find a significant relationship between interspecific variation in population trend and the change in potential range extent between the late 20(th) and late 21(st) centuries, forecasted by climatic envelope models. Our indicator measures divergence in population trend between bird species predicted by climatic envelope models to be favourably affected by climatic change and those adversely affected. The indicator shows a rapid increase in the past twenty years, coinciding with a period of rapid warming.

Birds are tracking climate warming, but not fast enough.

Range shifts of many species are now documented as a response to global warming. But whether these observed changes are occurring fast enough remains uncertain and hardly quantifiable. Here, we developed a simple framework to measure change in community composition in response to climate warming. This framework is based on a community temperature index (CTI) that directly reflects, for a given species assemblage, the balance between low- and high-temperature dwelling species. Using data from the French breeding bird survey, we first found a strong increase in CTI over the last two decades revealing that birds are rapidly tracking climate warming. This increase corresponds to a 91 km northward shift in bird community composition, which is much higher than previous estimates based on changes in species range edges. During the same period, temperature increase corresponds to a 273 km northward shift in temperature. Change in community composition was thus insufficient to keep up with temperature increase: birds are lagging approximately 182 km behind climate warming. Our method is applicable to any taxa with large-scale survey data, using either abundance or occurrence data. This approach can be further used to test whether different delays are found across groups or in different land-use contexts.

Functional homogenization effect of urbanization on bird communities.

We studied the community richness and dynamics of birds in landscapes recently affected by urbanization to test the prediction that biotic communities living in degraded landscapes are increasingly composed of generalist species. We analyzed bird communities in 657 plots monitored by the French Breeding Bird Survey from 2001 to 2005, accounting for the probability of species detection and spatial autocorrelation. We used an independent land-cover program to assess urbanization intensity in each FBBS plot, from 1992 to 2002. We found that urbanization induced community homogenization and that populations of specialist species became increasingly unstable with increasing urbanization of the landscape. Our results emphasize that urbanization has a substantial impact on the spatial component of communities and highlight the destabilizing effect of urbanization on communities over time. These results illustrate that urbanization may be a strong driving force in functional community composition and that measuring community homogenization is a powerful tool in the assessment of the effects of landscape changes and thus aides sustainable urban planning.

Expected impact of agriculture expansion on the world avifauna.

Agriculture expansion is a major cause of the current biodiversity decline. From the knowledge of the average bird densities in the terrestrial biomes, and using forecasts of biome conversions associated to agriculture expansion between 1990 and 2050, we estimate that these conversions would reduce by 8 to 26% the global avifauna, in number of individuals, depending on socio-economic scenarios and farmland management. Then, adding these values to previous estimates, we estimate that 27-44% of the bird species could be lost due to agriculture expansion from Neolithic to 2050.

Lower group productivity under kin-selected reproductive altruism.

Hamilton's rule provides the foundation for understanding the genetic evolution of social behavior, showing that altruism is favored by increased relatedness and increased productivity of altruists. But how likely is it that a new altruistic mutation will satisfy Hamilton's rule by increasing the reproductive efficiency of the group? Altruism per se does not improve efficiency, and hence we would not expect a typical altruistic mutation to increase the mean productivity of the population. We examined the conditions under which a mutation causing reproductive altruism can spread when it does not increase productivity. We considered a population divided into temporary groups of genetically similar individuals (typically family groups). We show that the spread of altruism requires a pleiotropic link between altruism and enhanced productivity in diploid organisms, but not in haplodiploid organisms such as Hymenoptera. This result provides a novel biological understanding of the barrier to the spread of reproductive altruism in diploids. In haplodiploid organisms, altruism within families that lowers productivity may spread, provided daughters sacrifice their own reproduction to raise full-sisters. We verified our results using three single-locus genetic models that explore a range of the possible reproductive costs of helping. The advantage of female-to-female altruism in haplodiploids is a well-known prediction of Hamilton's rule, but its importance in relaxing the linkage between altruism and efficiency has not been explored. We discuss the possible role of such unproductive altruism in the origins of sociality. We also note that each model predicts a large region of parameter space were polymorphism between altruism and selfishness is maintained, a pattern independent of dominance.

Thermal range predicts bird population resilience to extreme high temperatures.

The identification of the characteristics of species that make them susceptible or resilient to climate change has been elusive because non-climatic influences may dominate short- and medium-term changes in population and distribution sizes. Here we studied the 2003 French heat wave, during which other confounding variables remained essentially unchanged, with a correlational approach. We tested the relationship between population resilience and thermal range by analysing the responses of 71 bird species to a 6-month heat wave. Species with small thermal ranges showed the sharpest decreases in population growth rate between 2003 and 2004 in locations with the highest temperature anomalies. Thermal range explained the resilience of birds to the heat wave independently of other potential predictors, although it correlated with nest location and broad habitat type used by species. The geographically deduced thermal range appears to be a reliable predictor of the resilience of these endothermic species to extreme temperatures.

Spatial segregation of specialists and generalists in bird communities.

Each species generally has a close relationship with one or more habitats and can therefore be classified as either specialist or generalist. We studied whether specialist and generalist species are spatially distributed independently of each other. Repeating the analysis for 100 of the most frequent terrestrial bird species recorded over the 10 000 sampled sites of the French Breeding Bird survey, we found that specialists were more abundant if the rest of the community was specialized, and that the inverse was also true. This pattern was far subtler than just a simple dichotomy: most species actually presented a maximum abundance at a value of community specialization similar to their own level of specialization. Bird communities appear very well defined along a specialist-generalist gradient. We believe this pattern becomes more apparent with habitat degradation. The consequences on both ecological services and community resilience may well be considerable.

On the expected relationship between inbreeding, fitness, and extinction.

We assessed the expected relationship between the level and the cost of inbreeding, measured either in terms of fitness, inbreeding depression or probability of extinction. First, we show that the assumption of frequent, slightly deleterious mutations do agree with observations and experiments, on the contrary to the assumption of few, moderately deleterious mutations. For the same inbreeding coefficient, populations can greatly differ in fitness according to the following: (i) population size; larger populations show higher fitness (ii) the history of population size; in a population that recovers after a bottleneck, higher inbreeding can lead to higher fitness and (iii) population demography; population growth rate and carrying capacity determine the relationship between inbreeding and extinction. With regards to the relationship between inbreeding depression and inbreeding coefficient, the population size that minimizes inbreeding depression depends on the level of inbreeding: inbreeding depression can even decrease when population size increases. It is therefore clear that to infer the costs of inbreeding, one must know both the history of inbreeding (e.g. past bottlenecks) and population demography.

Evidence for the impact of global warming on the long-term population dynamics of common birds.

Taking the opportunity in 2003 of the exceptionally warm spring in France as a natural simulation of possible future climate, we analysed common bird productivity using the French long-term capture-recapture national monitoring scheme. Two-thirds of the 32 species studied had an above-average productivity in 2003. However, this gain in productivity was not consistent among species, with a relatively low productivity for species exhibiting a long-term decline and relatively high productivity for stable or increasing species. Such links between long-term and short-term dynamics suggest that the impact of increasingly warm springs on productivity is a major component of the recent population dynamics of a variety of common bird species.

Familial versus mass selection in small populations.

We used diffusion approximations and a Markov-chain approach to investigate the consequences of familial selection on the viability of small populations both in the short and in the long term. The outcome of familial selection was compared to the case of a random mating population under mass selection. In small populations, the higher effective size, associated with familial selection, resulted in higher fitness for slightly deleterious and/or highly recessive alleles. Conversely, because familial selection leads to a lower rate of directional selection, a lower fitness was observed for more detrimental genes that are not highly recessive, and with high population sizes. However, in the long term, genetic load was almost identical for both mass and familial selection for populations of up to 200 individuals. In terms of mean time to extinction, familial selection did not have any negative effect at least for small populations (N< or =50). Overall, familial selection could be proposed for use in management programs of small populations since it increases genetic variability and short-term viability without impairing the overall persistence times.

The evolution of autosomal suppressors of sex-ratio drive in Drosophila simulans.

Sex-ratio drive, which results in males siring female-biased progeny, has been reported in several Drosophila species, including D. simulans. It is caused by X-linked drivers that prevent the production of Y-bearing sperm. In natural populations of D. simulans, the drivers are usually cryptic, because their spread has elicited the evolution of drive suppressors. We investigated autosomal suppression in flies from Madagascar, Réunion and Kenya. Autosomal suppressors were found in all three places, indicating that they are a regular component of drive suppression over this geographic area, where strong Y-linked suppressors also occur. These suppressors were suspected of being polymorphic in Madagascar and Réunion and proved to be polymorphic in Kenya. We developed a model simulating the evolution of neutral autosomal suppressors in order to explore the effects of the number of suppressor genes, their relative strength and the co-occurrence of Y-linked suppressors. The most interesting prediction of the model is that when suppression is multigenic, suppressor loci can remain polymorphic despite the absence of balancing selection if an equal sex-ratio is restored in the population before the suppressor alleles become fixed at all loci. The model also emphasises the importance of the sterility of distorters' sons in suppressor dynamics.

Inbreeding depression and heterosis in a subdivided population: influence of the mating system.

We investigate the joint effects of gene flow and selfing on the level of inbreeding depression, heterosis and genetic load in a subdivided population at equilibrium. Low gene flow reduces inbreeding depression and substantially increases heterosis. However, in highly self-fertilizing populations, inbreeding depression is independent of the amount of gene flow. When migration occurs via pollen, consanguinity of the reproductive system could have a negative influence on subpopulation persistence, in contrast to the case of isolated populations. However, with only seed migration, genetic load and heterosis depend mildly on the mating system. From an evolutionary point of view, we reach two main conclusions: first, outcrossing is selected for if gene flow is low; second, intermediate levels of gene flow could promote mixed mating systems, especially when migration occurs through pollen.