Feeding innovations and parasitism in birds

The rate of behavioural innovation, such as opportunistic feeding innovation, may facilitate adaptation to novel environments. Because parasites may affect how their hosts adopt novel means of resource acquisition, or because opportunistic behaviours may involve the risk of being exposed to a large parasite fauna, we hypothesize an evolutionary link between the rate of feeding innovations and parasitism. We investigated the phylogenetic relationship between relative frequency of feeding innovations (adjusted for research effort and population size) and relative size of immune defense organs (as a relative measure of parasite-mediated selection) and the prevalence of blood parasites in birds. Using generalized least squares models, we found that species with relatively large bursa of Fabricius, thymus, and spleen had higher rates of feeding innovations than species with small immune defense organs. Similarly, there was a positive interspecific association between feeding innovation and haematozoa prevalence. These relationships were not confounded by migration, relative brain size, geographical distribution, and male plumage brightness. Analyses of causality relying on evolutionary modelling of discrete variables and path analysis suggest that increasing rate of feeding innovation may place species under intense selection due to parasitism. Therefore, behavioural adaptation by feeding innovation seems to have consequences for the coevolutionary arm race between parasites and hosts.  © 2007 The Linnean Society of London, Biological Journal of the Linnean Society , 2007, 90 , 441–455.     

Bats as prey of diurnal birds: a global perspective

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Ecological opportunity and diversification in a continental radiation of birds: climbing adaptations and cladogenesis in the Furnariidae

Ecological theories of adaptive radiation predict that ecological opportunity stimulates cladogenesis through its effects on competitive release and niche expansion. Given that key innovations may confer ecological opportunity, we investigated the effect of the acquisition of climbing adaptations on rates of cladogenesis in a major avian radiation, the Neotropical bird family Furnariidae, using a species-level phylogeny. Morphological specializations for vertical climbing originated in the woodcreepers ～23 million years ago, well before that adaptation occurred in woodpeckers (Picidae) or in other potential competitors in South America. This suggests that the acquisition of climbing adaptations conferred ample ecological opportunity to early woodcreepers. Nonetheless, we found that increases in speciation rates in Furnariidae did not coincide with the acquisition of climbing adaptations and that the relationship between the accumulation of climbing adaptations and rates of speciation was negative. In addition, we did not detect a diversity-dependent decline in woodcreeper diversification rates consistent with saturation of the trunk-climbing niche. These findings do not support the hypothesis that ecological opportunity related to trunk foraging stimulated cladogenesis in this radiation. The negative effect of climbing on diversification may be mediated by an indirect positive effect of climbing on dispersal ability, which may reduce speciation rates over evolutionary timescales.     

德国人文聚落区生态单元制图国家项目

联邦德国自然保护法、德国各州自然保护法要求在自然景观区和人文聚落区保护、管理和发展自然。实现这一法律要求 ,必须以现实的、全面的、高质量的、与自然保护原则相匹配的数据为基础。实践证明 ,城乡生态单元制图是获取和解释这些数据不可或缺的手段。德国人文聚落区生态单元制图始于 1 978年 ,同年组建成立了德国联邦与各州自然保护部门参加并联合协调的“人文聚落区生态单元制图工作组”。 1 986年工作组提出了德国人文聚落区生态单元制图基本方案 ,1 993年完成基本方案修订版。基本方案的目标是在全国范围建立标准制图方法 ,使获取的科学数据可以相互比较。至 2 0 0 0年 ,德国在人文聚落区生态单元制图项目上的投资约合 2亿马克 ;至 2 0 0 1年 3月 ,德国有 2 2 3个大中城市已经完成或正在实施生态单元制图 ,人文聚落区生态单元制图已经成为德国各级政府生态规划的基本工作内容。     

Identifying priority areas for conservation: a global assessment for forest-dependent birds

Limited resources are available to address the world's growing environmental problems, requiring conservationists to identify priority sites for action. Using new distribution maps for all of the world's forest-dependent birds (60.6% of all bird species), we quantify the contribution of remaining forest to conserving global avian biodiversity. For each of the world's partly or wholly forested 5-km cells, we estimated an impact score of its contribution to the distribution of all the forest bird species estimated to occur within it, and so is proportional to the impact on the conservation status of the world's forest-dependent birds were the forest it contains lost. The distribution of scores was highly skewed, a very small proportion of cells having scores several orders of magnitude above the global mean. Ecoregions containing the highest values of this score included relatively species-poor islands such as Hawaii and Palau, the relatively species-rich islands of Indonesia and the Philippines, and the megadiverse Atlantic Forests and northern Andes of South America. Ecoregions with high impact scores and high deforestation rates (2000-2005) included montane forests in Cameroon and the Eastern Arc of Tanzania, although deforestation data were not available for all ecoregions. Ecoregions with high impact scores, high rates of recent deforestation and low coverage by the protected area network included Indonesia's Seram rain forests and the moist forests of Trinidad and Tobago. Key sites in these ecoregions represent some of the most urgent priorities for expansion of the global protected areas network to meet Convention on Biological Diversity targets to increase the proportion of land formally protected to 17% by 2020. Areas with high impact scores, rapid deforestation, low protection and high carbon storage values may represent significant opportunities for both biodiversity conservation and climate change mitigation, for example through Reducing Emissions from Deforestation and Forest Degradation (REDD+) initiatives.     

The global distribution of frugivory in birds

Aim To examine patterns of avian frugivory across clades, geography and environments. Location Global, including all six major biogeographical realms (Afrotropics, Australasia, Indo‐Malaya, Nearctic, Neotropics and Palaearctic). Methods First, we examine the taxonomic distribution of avian frugivory within orders and families. Second we evaluate, with traditional and spatial regression approaches, the geographical patterns of frugivore species richness and proportion. Third, we test the potential of contemporary climate (water–energy, productivity, seasonality), habitat heterogeneity (topography, habitat diversity) and biogeographical history (captured by realm membership) to explain geographical patterns of avian frugivory. Results Most frugivorous birds (50%) are found within the perching birds (Passeriformes), but the woodpeckers and allies (Piciformes), parrots (Psittaciformes) and pigeons (Columbiformes) also contain a significant number of frugivorous species (9–15%). Frugivore richness is highest in the Neotropics, but peaks in overall bird diversity in the Himalayan foothills, the East African mountains and in some areas of Brazil and Bolivia are not reflected by frugivores. Current climate explains more variance in species richness and proportion of frugivores than of non‐frugivores whereas it is the opposite for habitat heterogeneity. Actual evapotranspiration (AET) emerges as the best single climatic predictor variable of avian frugivory. Significant differences in frugivore richness and proportion between select biogeographical regions remain after differences in environment (i.e. AET) are accounted for. Main conclusions We present evidence that both environmental and historical constraints influence global patterns of avian frugivory. Whereas water–energy dynamics possibly constrain frugivore distribution via indirect effects on food plants, regional differences in avian frugivory most likely reflect historical contingencies related to the evolutionary history of fleshy fruited plant taxa, niche conservatism and past climate change. Overall our results support an important role of co‐diversification and environmental constraints on regional assembly over macroevolutionary time‐scales.     

Key lessons for achieving biodiversity‐sensitive cities and towns

Australia's urban landscapes offer opportunities to marry socio‐economic and biodiversity conservation objectives. Yet, information is needed on what urban landscape and habitat features are important for wildlife. In this article, we draw together our research from southeastern Australia to describe key lessons for biodiversity‐sensitive cities and towns. Lesson 1: The effects of urbanization on wildlife extend into adjacent habitats. We recommend retaining large, undisturbed areas of habitat away from development, avoiding intensive development adjacent to important conservation areas, prioritizing areas of ecological and social significance, screening light and noise pollution at the urban fringe and around large nature reserves, and planting appropriately provenanced locally native species for public streetscapes, parks and gardens. Lesson 2: Strategic enhancement of urban greenspace offers biodiversity gains. We recommend increasing the total amount of greenspace cover, maintaining ecological structures as habitat islands, using landscaping techniques to minimize risks to human safety, and gardening with low‐flowering native shrubs. Lesson 3: Large old trees need to be managed for long‐term sustainability. We recommend retaining large old trees in new developments, increasing the maximum standing life of urban trees, protecting regenerating areas and planting more seedlings, supplementing habitat features associated with large trees, and ensuring that young trees have space to grow through time. Lesson 4: Education and engagement connects residents with nature and raises awareness. We recommend education programs to enhance opportunities for residents to experience and learn about biodiversity, engaging residents in the establishment and maintenance of wildlife habitat, providing ‘cues to care’, facilitating access to garden plants that benefit wildlife, and encouraging cat containment. These lessons provide an evidence‐base for implementing conservation and management actions to improve the capacity of our cities and towns to support a diverse and abundant biota.     

Feeding wild birds in gardens: A test of water versus food

Bird feeding in residential gardens is an increasingly popular human–wildlife interaction. In Australia, the practice is discouraged by most government and nongovernment wildlife conservation agencies, although advice varies and the most common recommendation is to provide water and habitat for birds rather than supplementary food. This study compares bird abundance and diversity when residents in a Melbourne municipality provide water for birds versus food. Bird abundance was greater when food was provided compared with water, but avian assemblages did not differ.     

Use of primates in research: a global overview

We assessed the use of nonhuman primates and nonhuman primate biological material in research by reviewing studies published in 2001 in peer-reviewed journals. The number and species of primates used, the origin of the animals, the type of study, the area of research of the investigation, and the location at which the research was performed were tabulated. Additionally, factors related to the animals that may have affected the outcome of the experiments were recorded. A total of 2,937 articles involving 4,411 studies that employed nonhuman primates or nonhuman primate biological material were identified and analyzed. More than 41,000 animals were represented in the studies published in 2001. In the 14% of studies for which re-use could be determined, 69% involved animals that had been used in previous experiments. Published studies most commonly used nonhuman primates or nonhuman primate biological material from the species Chlorocebus aethiops (19%), Macaca mulatta (18%), M. fascicularis (9%), and Papio spp. (6%). Of these studies, 54% were classified as in vitro studies, 14% as noninvasive, 30% as chronic, and 1% were considered acute. Nonhuman primates were primarily used in research areas in which they appear to be the most appropriate models for humans. The most common areas of research were microbiology (including HIV/AIDS (26%)), neuroscience (19%), and biochemistry/chemistry (12%). Most (84%) of the primate research published in 2001 was conducted in North America, Europe, and Japan. The animals and conditions under which they were housed and used were rarely described. Although it is estimated that nonhuman primates account for an extremely small fraction of all animals used in research, their special status makes it important to report the many husbandry and environmental factors that influence the research results generated. This analysis has identified that editors rarely require authors to provide comprehensive information concerning the subjects (e.g., their origin), treatment conditions, and experimental procedures utilized in the studies they publish. The present analysis addresses the use of primates for research, including the effects of a shortage of suitable nonhuman primate subjects in many research areas.     

How birds colonize cities: genetic evidence from a common waterbird,the Eurasian coot

Much effort has been devoted to identify ecological and life‐history traits which facilitate urban colonization by wild avian species, but surprisingly little is known about the population‐level mechanisms of urbanization processes. In general, two different patterns of urban colonization have been proposed: 1) the model of independent colonization predicts that birds colonize cities independently in different geographical regions; 2) the model of leapfrog colonization assumes a single colonization event, while additional urban populations are established from the initial urban populations. The aim of this paper was to determine the pattern of urban colonization in a common waterbird, the Eurasian coot Fulica atra. For this purpose, we analysed microsatellite variation in three pairs of urban and rural coot populations from central Poland. We found that a newly‐established urban population was genetically more similar to neighbouring rural populations than to long‐established urban populations, as indicated by the analysis of fixation index, genetic distance and Bayesian assignment of individuals to genetic clusters. These results are consistent with the model of independent colonization, where neighbouring rural populations are a source of individuals that colonize new urban areas. However, our analysis also showed significant differentiation between long‐established urban populations and adjacent rural populations, suggesting that genetic connectivity between two types of habitat decreases with increasing time since urbanization. Our study shows high complexity of urbanization processes in wild animal populations, as well as it underpins utility of molecular tools in studying population‐level mechanisms of urbanization.     

Predatory prokaryotes: an emerging research opportunity

Predatory prokaryotes have evolved a unique strategy of obtaining energy and biosynthetic materials from their surroundings: acquiring them from other living bacterial cells. These types of microbes have been found in a diverse variety of environments, and may play an important role in modulating microbial population structure and dynamics, as has been hypothesized for marine viruses and possibly protists. Only one genus of predatory bacterium, Bdellovibrio, has been extensively described and studied, though several other examples have been reported in the literature. In this review, the four basic strategies used by currently described predatory prokaryotes will be discussed: "wolfpack" group predation, epibiotic attachment, direct cytoplasmic invasion, and periplasmic invasion. Special adaptations to each approach will be considered, and compared overall to the genetic and biochemical characteristics of symbiotic or pathogenic prokaryotes living within eukaryotic cells. Two specific examples of predatory microbes, Bdellovibrio and Ensifer, will be described in terms of predation strategy, association with host cells, and host range. The prospects for bringing to bear the tools of molecular microbial genetics to the study of predatory prokaryotes will be explored, using current research with Bdellovibrio and Ensifer as examples.     

Common birds facing global changes: what makes a species at risk?

Climate change, habitat degradation, and direct exploitation are thought to threaten biodiversity. But what makes some species more sensitive to global change than others? Approaches to this question have relied on comparing the fate of contrasting groups of species. However, if some ecological parameter affects the fate of species faced with global change, species response should vary smoothly along the parameter gradient. Thus, grouping species into few, often two, discrete classes weakens the approach. Using data from the common breeding bird survey in France – a large set of species with much variability with respect to the variables considered – we show that a quantitative measure of habitat specialization and of latitudinal distribution both predict recent 13 year trends of population abundance among 77 terrestrial species: the more northerly distributed and the more specialized a species is, the sharper its decline. On the other hand, neither hunting status, migrating strategy nor body mass predicted population growth rate variation among common bird species. Overall, these results are qualitatively very similar to the equivalent relationships found among the British butterfly populations. This constitutes additional evidence that biodiversity in Western Europe is under the double negative influence of climate change and land use change.     

Landscape effects on birds in urban woodlands: an analysis of 34 Swedish cities

Aim To compare bird abundances in woodlands along gradients from the city centre to the peri‐urban area. To evaluate the importance of the proportion of woodland within the city and in the peri‐urban landscape to forest bird communities breeding in urban woodlands. To test whether fragmentation effects on birds were linked to the type of peri‐urban matrix. Location A total of 34 Swedish cities with > 10,000 inhabitants in south‐central Sweden. The study area covered 105,000 km², in which 84% of the Swedish population of 9.1 million lives. Methods Repeated point count surveys were conducted in 2004 in a total of 474 woodlands. General linear models were used to test for possible differences in abundance along urban to peri‐urban gradients, and to regress bird abundances in local urban woodlands on: (1) total woodland cover in the city, (2) total woodland cover in the peri‐urban landscape, (3) the interaction between woodland cover in the city and in the peri‐urban area, (4) region, and (5) human density. Results More than 12,000 individuals of 100 forest bird species were recorded. Of the 34 most common species detected, 13 bird species had higher abundances in urban than in peri‐urban woodlands, and seven species showed the opposite trend. The bird community of urban woodlands was characterized by species associated with deciduous forests and tree nesters, whereas the bird community of peri‐urban woodlands was characterized by species associated with coniferous woodland and ground nesters. Twelve species were significantly linearly associated with the proportion of urban woodland and/or the proportion of peri‐urban woodland, and a further eight species were associated with the interaction between these two factors. Local breeding bird abundances of four species were significantly positively associated with the proportion of urban woodland only in farmland‐dominated landscapes. Main conclusions Fragmentation effects on some urban birds are linked to the type of peri‐urban matrix. In farmland landscapes, peri‐urban woodlands may have been too scarce to act as a source of bird immigrants to fragmented urban woodlands. To maintain populations of specialized forest birds within cities in landscapes dominated by agriculture, it is of paramount importance to conserve any remaining urban woodlands.     

Open access :an opportunity for biomedical research

Open access within the scientific community depends on the scientific context and the practices of the field. In the biomedical domain, the communication of research results is characterised by the importance of the peer reviewing process, the existence of a hierarchy among journals and the transfer of copyright to the editor. Biomedical publishing has become a lucrative market and the growth of electronic journals has not helped lower the costs. Indeed, it is difficult for today's public institutions to gain access to all the scientific literature. Open access is thus imperative, as demonstrated through the positions taken by a growing number of research funding bodies, the development of open access journals and efforts made in promoting open archives. This article describes the setting up of an Inserm portal for publication in the context of the French national protocol for open-access self-archiving and in an international context.     

A global assessment of Bergmann's rule in mammals and birds

Bergmann's rule states that endotherms have a large body size in high latitudes and cold climates. However, previous empirical studies have reported mixed evidence on the relationships between body size and latitude, raising the question of why some clades of endotherms follow Bergmann's rule, whereas others do not. Here, we synthesized the interspecific relationships between body size and latitude among 16,187 endothermic species (5422 mammals and 10,765 birds) using Bayesian phylogenetic generalized linear mixed models to examine the strength and magnitude of Bergmann's rule. We further assessed the effect of biological and ecological factors (i.e., body mass categories, dietary guild, winter activity, habitat openness, and climate zone) on the variations in the body mass–latitude relationships by adding an interaction term in the models. Our results revealed a generally weak but significant adherence to Bergmann's rule among all endotherms at the global scale. Despite taxonomic variation in the strength of Bergmann's rule, the body mass of species within most animal orders showed an increasing trend toward high latitudes. Generally, large-bodied, temperate species, non-hibernating mammals, and migratory and open-habitat birds tend to conform to Bergmann's rule more than their relatives do. Our results suggest that whether Bergmann's rule applies to a particular taxon is mediated by not only geographic and biological features, but also potential alternate strategies that species might have for thermoregulation. Future studies could explore the potential of integrating comprehensive trait data into phylogenetic comparative analysis to re-assess the classic ecogeographic rules on a global scale.     

Tourism as a threat to critically endangered and endangered birds: global patterns and trends in conservation hotspots

More than 12 % of bird species are threatened with extinction. Numerous anthropogenic activities and processes are considered responsible for such declines, including tourism related activities. These activities often occur in global biodiversity hotspots but few studies consider the potential risks associated with tourism. The relative importance of tourism as a threat to birds was quantified using a global analysis of the threats facing critically endangered and endangered birds in the hotspots. Sixty-three critically endangered and endangered bird species are reportedly threatened by tourism. Among those 63 species, marine, coastal and aquatic birds are threatened more by tourism than was expected. Hotspots with the most species threatened by tourism are Polynesia–Micronesia and the Mediterranean Basin. This study uses individual threatening processes in a new way to characterise hotspots for conservation action, advancing previous identification criteria. Analysing hotspots in terms of the relative presence of individual threatening processes may help to more effectively direct future research in these priority regions.     

Breeding synchrony in colonial birds: from local stress to global harmony

Why and how birds in colonies often breed in striking synchrony is an unsolved question. In colonies, conspecific birds often destroy eggs and kill chicks, either intentionally or not. We propose that social tranquillity at the time of laying can be achieved if a bird's stress level is partly determined by the agitation of its neighbours. Moreover, we propose that this local process, together with environmental cues, can synchronize breeding between neighbours and through a whole colony. We tested our hypotheses using a generic individual-based model where the breeding predisposition of females was updated daily depending on an increase in the photoperiod (positively) and the stress level of neighbours: negatively if they were agitated, and positively otherwise. A female laid her eggs when her stress level fell to a critical value. Even giving only a low relevance to the neighbour's stress level was enough to synchronize the laying date of neighbours and also of a huge colony. Moreover, females bred in a safer environment, which is known from field studies to increase fitness. Our study highlights the power of local adaptive (individual) behaviour to create global (colony) patterns. We argue that collective patterns such as breeding synchrony in colonial birds could have simple adaptive individual-level explanations.     

Shaken not stirred: a global research cocktail served in Hinxton

A report of the 2007 Cold Spring Harbor Laboratory/Wellcome Trust Conference on Functional Genomics and Systems Biology, Hinxton, UK, 10-13 October 2007.