Life-history strategies of Neotropical birds differ markedly from their Nearctic counterparts, yet the lack of detailed information on most Neotropical species hinders meaningful comparisons. We performed a gap analysis with several basic life-history traits of New World flycatchers of the subfamily Fluvicolinae. We found breeding data -mostly on clutch sizes and linear egg measurements -in 303 publications spanning the years 1838 to 2012. Data from the USA and Argentina were more abundant, with the number of publications per country being significantly and positively related to human development index (HDI) and Fluvicolinae breeding species richness. The amount of available clutch size information for each species was positively related to species' range size and relative abundance. More research is needed concerning narrowly distributed and uncommon species. Additional efforts to gather data on all Neotropical species are, however, crucial for future advancements.

Aim The aim of this study was to conduct comprehensive phylogeographic and demographic analyses to examine the degree to which topographic and climatic conditions have affected the patterns of diversification and migration in a strictly montane inhabitant, the montane long‐tailed mole (Scaptonyx fusicaudus). Location The mountains of south‐western China and adjacent mountains including Mts. Bashan, Dalou and Qinling also known as the sky islands in south‐western China. Taxon The long‐tailed mole (S. fusicaudus), a semi‐fossorial mammal distributed in the sky islands of south‐western China, is a relict species and the sole representative of the tribe Scaptonychini. Methods We sequenced one mitochondrial and six nuclear genes from 113 samples across the species’ range. We estimated phylogenetic relationships and divergence times, conducted genetic structuring and species delimitation using multiple approaches and used Approximate Bayesian Computation to test potential gene flow. We conducted ecological niche modelling to predict the species’ potential distribution in the present, the last glacial maximum and the last interglacial (LIG). Results The species comprises a minimum of 17 operational taxonomic units which are isolated in different mountain ranges. The lowlands and large rivers act as barriers to dispersal, and have isolated evolutionary lineages for up to 11 million years. Long‐distance dispersal is evident among a few discrete montane archipelagos. Suitable climatic conditions during the LIG are limited to only a few sites, thus geographically restricting climatic stable areas across geological periods (from the LIG to the present). Main conclusions For low‐vagility species, the complex topography of the sky islands has promoted exceptional diversification through a combination of eco‐environmental stability as well as geographic fragmentation. The mountains have acted as a buffer against climate change, and have provided continuously suitable habitats for S. fusicaudus since the early Late Miocene, supporting the hypothesis that the sky islands constitute “museums” of ancient lineages. Lowlands and river valleys have acted as barriers preventing gene flow, while the montane archipelagos could have provided stepping stones to facilitate dispersal.

N. M. Heming (heming@unb.br), Programa de P ó s-gradua ç ã o em Ecologia, IB, Univ. de Bras í lia, Bras í lia, Brazil, and Depto de Zoologia, IB, Univ. de Bras í lia, Bras í lia, Brazil. -M. Â . Marini, Depto de Zoologia, IB, Univ. de Bras í lia, Bras í lia, Brazil. Geographical variation in egg size is well documented for several taxa, but remains insuffi ciently described for birds in spite of a well-known latitudinal gradient in clutch size. Several hypotheses have been proposed to explain avian egg size variation; however, they were not tested on a continental scale. Egg size is a key component of reproductive investment that infl uences off spring fi tness. It is thought to vary geographically as one of a set of correlated life-history traits that are under selection from varying ecological conditions. We completed a comprehensive literature review and calculated egg sizes for the most widespread clade within tyrant fl ycatchers, describing for the fi rst time the geographical variation in egg size on a continental scale. We examined the relative support for ecological and environmental variables in explaining egg size variation using multi-model inference and linear mixed models controlled for phylogenetic autocorrelation among species. We tested fi ve hypotheses and found that: larger eggs occur in colder sites, which is consistent with the embryonic temperature hypothesis; medium/long-distance migrants had smaller eggs than resident species while short-distance migrants had the largest eggs; neither species clutch size, nor species nest type, nor evapotranspiration seasonality infl uenced egg size. Avian egg size is larger in Austral and Neotropical America (ANA), where species are resident or short-distance migrants, and smaller across the medium/long-distance migrants of the Nearctic region. In addition, while clutch size increases towards higher northern latitudes and is almost invariable across ANA species, egg sizes vary largely across ANA sites, increasing with southern latitudes and higher elevations and being infl uenced by summer temperature. While the embryonic temperature hypothesis has been usually linked to parental nest attentiveness, we highlight that environmental temperatures also have strong eff ects in shaping investment in egg size.

Populus tremuloides is the widest‐ranging tree species in North America and an ecologically important component of mesic forest ecosystems displaced by the Pleistocene glaciations. Using phylogeographic analyses of genome‐wide SNPs (34,796 SNPs, 183 individuals) and ecological niche modeling, we inferred population structure, ploidy levels, admixture, and Pleistocene range dynamics of P. tremuloides, and tested several historical biogeographical hypotheses. We found three genetic lineages located mainly in coastal–Cascades (cluster 1), east‐slope Cascades–Sierra Nevadas–Northern Rockies (cluster 2), and U.S. Rocky Mountains through southern Canadian (cluster 3) regions of the P. tremuloides range, with tree graph relationships of the form ((cluster 1, cluster 2), cluster 3). Populations consisted mainly of diploids (86%) but also small numbers of triploids (12%) and tetraploids (1%), and ploidy did not adversely affect our genetic inferences. The main vector of admixture was from cluster 3 into cluster 2, with the admixture zone trending northwest through the Rocky Mountains along a recognized phenotypic cline (Utah to Idaho). Clusters 1 and 2 provided strong support for the “stable‐edge hypothesis” that unglaciated southwestern populations persisted in situ since the last glaciation. By contrast, despite a lack of clinal genetic variation, cluster 3 exhibited “trailing‐edge” dynamics from niche suitability predictions signifying complete northward postglacial expansion. Results were also consistent with the “inland dispersal hypothesis” predicting postglacial assembly of Pacific Northwestern forest ecosystems, but rejected the hypothesis that Pacific‐coastal populations were colonized during outburst flooding from glacial Lake Missoula. Overall, congruent patterns between our phylogeographic and ecological niche modeling results and fossil pollen data demonstrate complex mixtures of stable‐edge, refugial locations, and postglacial expansion within P. tremuloides. These findings confirm and refine previous genetic studies, while strongly supporting a distinct Pacific‐coastal genetic lineage of quaking aspen.

The ~1.97 million egg sets (~5 million eggs) housed in museums have not been used in proportion to their availability. We highlight the wide variety of scientific disciplines that have used egg collections and the geographic locations and sizes of these collections, to increase awareness of the importance of egg collections, improve their visibility to the scientific community, and suggest that they offer a wealth of data covering large spatial scales and long time series for broad investigations into avian biology. We provide a brief history of egg collections and an updated list of museums/institutions with egg collections worldwide. We also review the limitations, challenges, and management of egg collections, and summarize recent literature based on historical and recent museum egg materials.

Aim: Changes in climatic conditions are predicted to impact species distribution and hence alter their diversity patterns. Modifications in the composition of biological communities are expected as a result of the loss and replacement of species due to global warming. Forest frugivorous birds already suffer from habitat loss and may disappear locally due to suitable area contraction or range shifts to novel areas, disrupting seed dispersal and consequently the functioning of natural ecosystems. Here, we investigate the impacts of different climate scenarios on alpha and beta diversities of forest frugivorous birds.Location: Central Corridor of the Atlantic Forest (CCAF), Brazil. Methods:We used ecological niche models to project species distribution of 68 frugivorous birds for the baseline and future (2050 and 2070) scenarios. We generated binary maps of suitable areas for each species by climate scenario to calculate alpha and beta diversities.Results: Most forest frugivorous birds were projected to lose suitable area, as a consequence of climate change, reducing alpha diversity in future scenarios and increasing temporal beta diversity, which is dominated by the nestedness component. In addition, species richness decreased from the east to the west portion of the CCAF, while differentiation of bird communities increased in the same direction, a pattern consistent across all climate scenarios evaluated.Main conclusions: Climate change may exert drastic alterations in the composition of frugivorous bird communities in the CCAF. As forest frugivorous birds are critical to seed dispersal of forest plant species, impoverishment of their communities can drastically affect forest regeneration, diversity, and structure in the decades to come. Therefore, a better comprehension of spatio-temporal changes in diversity patterns of frugivorous birds can help us to avoid the disruption of seed dispersal and its consequences, such as cascading effects that will trigger biodiversity loss in the CCAF.

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