Biodiversity is declining from unprecedented land conversions that replace diverse, low-intensity agriculture with vast expanses under homogeneous, intensive production. Despite documented losses of species richness, consequences for β-diversity, changes in community composition between sites, are largely unknown, especially in the tropics. Using a 10-year data set on Costa Rican birds, we find that low-intensity agriculture sustained β-diversity across large scales on a par with forest. In high-intensity agriculture, low local (α) diversity inflated β-diversity as a statistical artefact. Therefore, at small spatial scales, intensive agriculture appeared to retain β-diversity. Unlike in forest or low-intensity systems, however, high-intensity agriculture also homogenised vegetation structure over large distances, thereby decoupling the fundamental ecological pattern of bird communities changing with geographical distance. This ~40% decline in species turnover indicates a significant decline in β-diversity at large spatial scales. These findings point the way towards multi-functional agricultural systems that maintain agricultural productivity while simultaneously conserving biodiversity.

Peer reviewed eScholarship.orgPowered by the California Digital Library University of California of committing a moral act later (Fig. 4). In addition, a moral self-licensing pattern emerged (18), such that committing a moral act earlier in the day was associated with an above-average likelihood of a subsequent immoral act and a decreased likelihood of a subsequent moral act (Fig. 4). Together, the analysis of everyday moral dynamics revealed evidence both for moral contagion through other people's good deeds and moral self-licensing through one's own good deeds outside of the laboratory. Given these different mechanisms, it seems important to find out more about how the principles of moral contagion can be used in public policy interventions, and how moral slacking may be prevented. By tracking people's everyday moral experiences, we corroborated well-controlled but artificial laboratory research, refined prior predictions, and made illuminating discoveries about how people experience and structure morality, as well as about how morality affects people's happiness and sense of purpose. A closer, ecologically valid look at how morality unfolds in people's natural environments may inspire new models and theories about what it means to lead the "good" or "bad" life. Psychol. 4, 1-32 (2008). 12. J. Graham et al., J. Pers. Soc. Psychol. 101, 366-385 (2011). 13. J. Haidt, J. Graham, Soc. Justice Res. 20, 98-116 (2007. 14. J. Graham et al., Adv. Exp. Soc. Psychol. 47, 55-130 (2013 Habitat conversion is the primary driver of biodiversity loss, yet little is known about how it is restructuring the tree of life by favoring some lineages over others. We combined a complete avian phylogeny with 12 years of Costa Rican bird surveys (118,127 detections across 487 species) sampled in three land uses: forest reserves, diversified agricultural systems, and intensive monocultures. Diversified agricultural systems supported 600 million more years of evolutionary history than intensive monocultures but 300 million fewer years than forests. Compared with species with many extant relatives, evolutionarily distinct species were extirpated at higher rates in both diversified and intensive agricultural systems. Forests are therefore essential for maintaining diversity across the tree of life, but diversified agricultural systems may help buffer against extreme loss of phylogenetic diversity.A s human-converted habitats expand over Earth's surface, the fate of global biodiversity will depend increasingly on the quality and characteristics of farming landscapes (1, 2). Agricultural systems vary widely in their ability to support biodiversity, with many species extirpated from some but sustained in others (1, 3). Additionally, characteristics of the species themselves, evolved over millions of years, may predispose some lineages to benefit (or suffer) from human environmental impacts (4-6).Phylogenetic diversity, the total evolutionary history or phylogenetic branch lengths of all species in a community (7), is recognized as having intr...

Land-use change and climate change are driving a global biodiversity crisis. Yet, how species' responses to climate change are correlated with their responses to land-use change is poorly understood. Here, we assess the linkages between climate and land-use change on birds in Neotropical forest and agriculture. Across > 300 species, we show that affiliation with drier climates is associated with an ability to persist in and colonise agriculture. Further, species shift their habitat use along a precipitation gradient: species prefer forest in drier regions, but use agriculture more in wetter zones. Finally, forest-dependent species that avoid agriculture are most likely to experience decreases in habitable range size if current drying trends in the Neotropics continue as predicted. This linkage suggests a synergy between the primary drivers of biodiversity loss. Because they favour the same species, climate and land-use change will likely homogenise biodiversity more severely than otherwise anticipated.

The consequences of biodiversity decline in intensified agricultural landscapes hinge on surviving biotic assemblages. Maintaining crucial ecosystem processes and services requires resilience to natural and anthropogenic disturbances. However, the resilience and stability of surviving biological communities remain poorly quantified. From a 10-y dataset comprising 2,880 bird censuses across a land-use gradient, we present three key findings concerning the resilience and stability of Costa Rican bird communities. First, seed dispersing, insect eating, and pollinating guilds were more resilient to low-intensity land use than high-intensity land use. Compared with forest assemblages, bird abundance, species richness, and diversity were all ∼15% lower in low-intensity land use and ∼50% lower in high-intensity land use. Second, patterns in species richness generally correlated with patterns in stability: guilds exhibited less variation in abundance in low-intensity land use than in high-intensity land use. Finally, interspecific differences in reaction to environmental change (response diversity) and possibly the portfolio effect, but not negative covariance of species abundances, conferred resilience and stability. These findings point to the changes needed in agricultural production practices in the tropics to better sustain bird communities and, possibly, the functional and service roles that they play.

Earth is experiencing multiple global changes that will, together, determine the fate of many species. Yet, how biological communities respond to concurrent stressors at local-to-regional scales remains largely unknown. In particular, understanding how local habitat conversion interacts with regional climate change to shape patterns in b-diversity-differences among sites in their species compositions-is critical to forecast communities in the Anthropocene. Here, we study patterns in bird b-diversity across land-use and precipitation gradients in Costa Rica. We mapped forest cover, modeled regional precipitation, and collected data on bird community composition, vegetation structure, and tree diversity across 120 sites on 20 farms to answer three questions. First, do bird communities respond more strongly to changes in land use or climate in northwest Costa Rica? Second, does habitat conversion eliminate b-diversity across climate gradients? Third, does regional climate control how communities respond to habitat conversion and, if so, how? After correcting for imperfect detection, we found that local land-use determined community shifts along the climate gradient. In forests, bird communities were distinct between sites that differed in vegetation structure or precipitation. In agriculture, however, vegetation structure was more uniform, contributing to 7%-11% less bird turnover than in forests. In addition, bird responses to agriculture and climate were linked: agricultural communities across the precipitation gradient shared more species with dry than wet forest communities. These findings suggest that habitat conversion and anticipated climate drying will act together to exacerbate biotic homogenization.