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Anticipating species’ responses to environmental change is a pressing mission in biodiversity conservation. Despite decades of research investigating how climate change may affect population sizes, historical context is lacking and the traits which mediate demographic sensitivity to changing climate remain elusive. We use whole-genome sequence data to reconstruct the demographic histories of 263 bird species over the past million years and identify networks of interacting morphological and life-history traits associated with changes in effective population size (Ne) in response to climate warming and cooling. Our results identify direct and indirect effects of key traits representing dispersal, reproduction, and survival on long-term demographic responses to climate change, thereby highlighting traits most likely to influence population responses to on-going climate warming.One-Sentence SummaryInteracting traits influence sensitivity of bird population sizes to climate warming and cooling over the past million years.

Despite evidence of declining biosphere integrity, we currently lack understanding of how the functional diversity associated with changes in abundance among ecological communities has varied over time and before widespread human disturbances. We combine morphological, ecological, and life-history trait data for >260 extant bird species with genomic-based estimates of changing effective population size (Ne) to quantify demographic-based shifts in avian functional diversity over the past million years and under pre-anthropogenic climate warming. We show that functional diversity was relatively stable over this period, but underwent significant changes in some key areas of trait space due to changing species abundances. Our results suggest that patterns of population decline over the Pleistocene have been concentrated in particular regions of trait space associated with extreme reproductive strategies and low dispersal ability, consistent with an overall erosion of functional diversity. Further, species most sensitive to climate warming occupied a relatively narrow region of functional space, indicating that the largest potential population increases and decreases under climate change will occur among species with relatively similar trait sets. Overall, our results identify fluctuations in functional space of extant species over evolutionary timescales and represent the demographic-based vulnerability of different regions of functional space among these taxa. The integration of paleodemographic dynamics with functional trait data enhances our ability to quantify losses of biosphere integrity before anthropogenic disturbances and attribute contemporary biodiversity loss to different drivers over time. Despite evidence of declining biosphere integrity, we currently lack understanding of how the functional diversity associated with changes in abundance among ecological communities has varied over time and before widespread human disturbances. We combine morphological, ecological, and life-history trait data for >260 extant bird species with genomic-based estimates of changing effective population size (Ne) to quantify demographic-based shifts in avian functional diversity over the past million years and under pre-anthropogenic climate warming. We show that functional diversity was relatively stable over this period, but underwent significant changes in some key areas of trait space due to changing species abundances. Our results suggest that patterns of population decline over the Pleistocene have been concentrated in particular regions of trait space associated with extreme reproductive strategies and low dispersal ability, consistent with an overall erosion of functional diversity. Further, species most sensitive to climate warming occupied a relatively narrow region of functional space, indicating that the largest potential population increases and decreases under climate change will occur among species with relatively similar trait sets. Overall, our results identify fluctuations in functional space of extant species over evolutionary timescales and represent the demographic-based vulnerability of different regions of functional space among these taxa. The integration of paleodemographic dynamics with functional trait data enhances our ability to quantify losses of biosphere integrity before anthropogenic disturbances and attribute contemporary biodiversity loss to different drivers over time.

Extinction leads to restructuring By most accounts, human activities are resulting in Earth's sixth major extinction event, and large-bodied mammals are among those at greatest risk. Loss of such vital ecosystem components can have substantial impacts on the structure and function of ecological systems, yet fully understanding these effects is challenging. Tóth et al. looked at the loss of large-bodied mammals in the Pleistocene epoch to identify potential community assembly effects. They found that the demise of large mammals led to a restructuring and a shift from biotic to abiotic drivers of community structure. Understanding past changes may help predict the community-level effects of the extinctions we are currently driving. Science , this issue p. 1305

Whole-genome sequencing projects are increasingly populating the tree of life and characterizing biodiversity1–4. Sparse taxon sampling has previously been proposed to confound phylogenetic inference5, and captures only a fraction of the genomic diversity. Here we report a substantial step towards the dense representation of avian phylogenetic and molecular diversity, by analysing 363 genomes from 92.4% of bird families—including 267 newly sequenced genomes produced for phase II of the Bird 10,000 Genomes (B10K) Project. We use this comparative genome dataset in combination with a pipeline that leverages a reference-free whole-genome alignment to identify orthologous regions in greater numbers than has previously been possible and to recognize genomic novelties in particular bird lineages. The densely sampled alignment provides a single-base-pair map of selection, has more than doubled the fraction of bases that are confidently predicted to be under conservation and reveals extensive patterns of weak selection in predominantly non-coding DNA. Our results demonstrate that increasing the diversity of genomes used in comparative studies can reveal more shared and lineage-specific variation, and improve the investigation of genomic characteristics. We anticipate that this genomic resource will offer new perspectives on evolutionary processes in cross-species comparative analyses and assist in efforts to conserve species., A dataset of the genomes of 363 species from the Bird 10,000 Genomes Project shows increased power to detect shared and lineage-specific variation, demonstrating the importance of phylogenetically diverse taxon sampling in whole-genome sequencing.

Limnothlypis swainsonii (Swainson's Warbler) readily colonizes novel habitat formations that meet basic requirements for understory stem density and visual screening. Little is known about the warbler's behavioral response to naturalized populations of introduced plants. I surveyed the incidence of introduced invasive Ligustrum spp. (privet) and native Arundinaria spp. (cane) on breeding territories (n = 590) of Swainson's Warbler in the southeastern United States. Privet occurred frequently on territories in Mississippi (65.0%), Alabama (55.7%), Louisiana (52.8%), and Texas (39.5%). Territories with privet (49.6% of total) were observed in 90 counties and parishes. The survey revealed numerous instances of warbler territories located in near-monocultures of Ligustrum sinense (Chinese Privet). Territories with cane (33.1% of total) were observed in 72 counties and parishes. In a broader context, the survey data suggest that Swainson's Warbler populations have rapidly adapted to invasive privets, which are physiognomically similar to several native thicket-forming shrubs.

The ornamental plant Lagerstroemia indica (Crapemyrtle) was introduced to American gardens before 1796, but little is known about its use as a food resource by avian species. Local wintering populations of Spinus tristis (American Goldfinch), Junco hyemalis (Dark-eyed Junco), and Haemorhous mexicanus (House Finch) feed heavily on Crapemyrtle seeds, and I observed 5 additional bird species occasionally extracting seeds from dehiscent capsules in Fairfax County, VA. Planted and naturalized Crapemyrtle may be an important food resource for finches and sparrows in southeastern US.

The first isotopic baseline is established for the snail Neohelix from the Big Santeetlah Creek watershed (Appalachian Mountains). Shell δ18O (− 3.6 to + 0.4‰) declined with altitude 0.06‰ per 100 m and correlated with measured rain δ18O. A flux balance model suggests that relative humidity increased from ~ 0.89 at 710 m to ~ 0.91 at 1620 m, in agreement with higher precipitation at higher altitudes. Coherent relationships between shell, precipitation and humidity suggest that this taxon should be a valid paleoprecipitation archive in North America. The respective δ13C and δ15N values of body (− 28.3 to − 23.2‰; + 0.4 to + 4.9‰) and shell organics (− 28.2 to − 24.0‰; + 0.0 to + 3.4‰) did not exhibit a trend with altitude and were uncorrelated with potential food resources. A stable isotope-mixing model suggests that Neohelix primarily consume fungi (~ 48%) and lichen (~ 17%), with minimal ingestion of C3 plants. The relative contributions of different food items, however, varied in an unpredictable fashion along the altitudinal gradient. This study illustrates that even though snail foraging ecology from woodlands is complex and more variable than anticipated, combining several isotope systems permits dietary inferences more easily than field observations alone.

Resumen Los buitres del Nuevo Mundo (Cathartidae) estan expuestos de manera cronica a bacterias patogenas debido a su dieta carronera. Se ha hipotetizado que la fuerte acidez gastrointestinal actua como un filtro robusto que reduce significativamente la diversidad bacteriana en el alimento a medida que progresa a lo largo del aparato digestivo. Sin embargo, no existen datos publicados sobre el pH gastrointestinal de los buitres de este clado monofiletico. En este estudio, presento las primeras mediciones postprandiales (despues de la alimentacion) del pH gastrointestinal para Coragyps atratus (n = 13 individuos), Cathartes burrovianus (n = 5) y Cathartes aura (n = 2). La variacion en el pH estomacal observado (2.0–5.6) probablemente estuvo relacionada con el llenado estomacal, la dilucion concomitante de los jugos gastricos por la ingesta de carrona y el tiempo desde la ultima alimentacion. Los valores circumneutrales observados en el intestino delgado (pH 5.6–7.3) y el intestino grueso (pH 5.9–7.3) de lo...

In this comprehensive survey of microbiomes of >900 species, including 315 mammals and 491 birds, we find a striking convergence of the microbiomes of birds and animals that fly. In nonflying mammals, diet and short-term evolutionary relatedness drive the microbiome, and many microbial species are specific to a particular kind of mammal, but flying mammals and birds break this pattern with many microbes shared across different species, with little correlation either with diet or with relatedness of the hosts. This finding suggests that adaptation to flight breaks long-held relationships between hosts and their microbes., Diet and host phylogeny drive the taxonomic and functional contents of the gut microbiome in mammals, yet it is unknown whether these patterns hold across all vertebrate lineages. Here, we assessed gut microbiomes from ∼900 vertebrate species, including 315 mammals and 491 birds, assessing contributions of diet, phylogeny, and physiology to structuring gut microbiomes. In most nonflying mammals, strong correlations exist between microbial community similarity, host diet, and host phylogenetic distance up to the host order level. In birds, by contrast, gut microbiomes are only very weakly correlated to diet or host phylogeny. Furthermore, while most microbes resident in mammalian guts are present in only a restricted taxonomic range of hosts, most microbes recovered from birds show little evidence of host specificity. Notably, among the mammals, bats host especially bird-like gut microbiomes, with little evidence for correlation to host diet or phylogeny. This suggests that host-gut microbiome phylosymbiosis depends on factors convergently absent in birds and bats, potentially associated with physiological adaptations to flight. Our findings expose major variations in the behavior of these important symbioses in endothermic vertebrates and may signal fundamental evolutionary shifts in the cost/benefit framework of the gut microbiome.

This paper reports the first record of a territorial Limnothlypis swainsonii (Swainson's Warbler) associated with the invasive Reynoutria japonica (Japanese Knotweed). The observation adds to a growing body of literature documenting rapid behavioral adaptation to novel habitats in this globally rare warbler.

In Supplementary Table 1 of this Article, 23 samples (B10K-DU-029-32, B10K-DU-029-33, B10K-DU-029-36 to B10K-DU-029-44, B10K-DU- 029-46, B10K-DU-029-47, B10K-DU-029-49 to B10K-DU-029-53, B10K-DU- 029-75 to B10K-DU-029-77, B10K-DU-029-80, and B10K-DU-030-03; styled in boldface in the revised table) were assigned to the incorrect institution. Supplementary Table 1 has been amended to reflect the correct source institution for these samples, and associated data (tissue, museum ID/source specimen ID, site, state/province, latitude, longitude, date collected and sex) have been updated accordingly. The original table is provided as Supplementary Information to this Amendment, and the original Article has been corrected online.

Sexual dimorphism patterns in wing area, wing loading, and wing aspect ratio of Black Vulture (Coragyps atratus) and Turkey Vulture (Cathartes aura) are unknown but are of particular interest given the prevalence of these species in scavenging communities in the Western Hemisphere. I assessed these variables in sexed specimens from wintering populations in Nashville, Tennessee. Black Vultures exhibited higher wing loading and a lower wing aspect ratio than Turkey Vultures. Neither species exhibited significant age-related or sexual dimorphism in body weight, wing span, wing area, wing loading, or wing aspect ratio. The relatively low variance observed in the pooled sample of immatures (∼9–21 mo old) and adults suggests that definitive wing size and shape are acquired several years before individuals develop the bare rugose skin and head caruncles characteristic of adults. In a broader context, this study tentatively suggests that variance estimates for wing morphology obtained from unsexed vultur...

The most intensively studied breeding population of Limnothlypis swainsonii (Swainson's Warbler) is in the White River watershed of southeastern Arkansas. However, because vegetation sampling protocols employed at this site have been significantly different from those used elsewhere, it has been difficult for land managers to reconcile datasets across the species' range in order to construct consensus quantitative benchmarks for optimal breeding habitat in bottomland hardwoods. We used a standardized sampling protocol to compare the physiognomic and floristic characteristics of breeding territories at 2 sites in the White River watershed with comparable data from other populations in Arkansas, Mississippi, Louisiana, Florida, and Virginia. Breeding territories in the combined dataset for this rare migratory species varied substantially in successional stage, floristic diversity, hydrology, and management history. Visual screening provided by understory thickets of saplings, vine tangles, and shru...

Fieldwork in the Ozark Mountains of the central United States by GRG over the last decade involving the American smoketree, Cotinus obovatus Raf. (Anacardiaceae), has resulted in the discovery of a previously unknown moth species belonging to the genus Cameraria (Lepidoptera: Gracillariidae). The larva of this species mines the leaf mesophyll of this tree, creating serpentine mines most visible from the upper (adaxial) surface of the leaf. The most closely related species to Cameraria cotinivora, n. sp. is Cameraria guttifinitella (Clemens), a common leafminer of poison ivy, Toxicodendron radicans (L.) Kuntze (Anacardiaceae). Illustrations of both species are provided as well as a COI analysis of their genetic relationship.

The naked heads of Cathartes vultures are widely believed to be adaptations for temperature regulation and to reduce plumage fouling during carrion feeding. Bright head color and the elaborate pattern of caruncles on the head and neck skin have a likely function in intra- and interspecific signaling. These integumentary characters have been difficult to study because of extensive postmortem color fading and shrinkage in museum specimens. Here I provide the first detailed description of head color and caruncles of the Greater Yellow-headed Vulture (C. melambrotus) from freshly collected specimens and provide comparative notes on sympatric populations of the Turkey Vulture (C. aura) and Lesser Yellow-headed Vulture (C. burrovianus) from Guyana.

Although the breeding ranges of Archilochus alexandri (Black-chinned Hummingbird) and Archilochus colubris (Ruby-throated Hummingbird) are narrowly parapatric in central Texas and central and southern Oklahoma, there have been few reports of hybridization in the literature and no well-documented hybrid specimens. Here we provide a comprehensive assessment of two male hybrids collected, respectively, in Grayson County, Texas, and East Baton Rouge Parish, Louisiana. As has been the pattern in other hummingbird hybrids, both specimens exhibit a blended mosaic of plumage characters of the parental species. Sequence for mitochondrial cytochrome c oxidase subunit 1 (CO1) for the hybrid specimen from East Baton Rouge Parish (LSU 182,831) confirms A. colubris as the female parent.

Archilochus colubris (Ruby-throated Hummingbird) invariably decorate the exterior surface of their nests with living foliose lichen. Lichen fragments may be carried considerable distances, but it is unknown whether transported thalli survive at nest sites. Here we report the multi-year persistence of a transported thallus of Myelochroa aurulenta (Powdery Axil-bristle Lichen) at a hummingbird nest site. Our observation suggests that hummingbirds may be important dispersal agents for foliose lichens.

Recent reviews identified the reliance on fecal or cloacal samples as a significant limitation hindering our understanding of the avian gastrointestinal (gut) microbiota and its function. We investigated the microbiota of the esophagus, duodenum, cecum, and colon of a wild urban population of Canada goose (Branta canadensis). From a population sample of 30 individuals, we sequenced the V4 region of the 16S SSU rRNA on an Illumina MiSeq and obtained 8,628,751 sequences with a median of 76,529 per sample. These sequences were assigned to 420 bacterial OTUs and a single archaeon. Firmicutes, Proteobacteria, and Bacteroidetes accounted for 90% of all sequences. Microbiotas from the four gut regions differed significantly in their richness, composition, and variability among individuals. Microbial communities of the esophagus were the most distinctive whereas those of the colon were the least distinctive, reflecting the physical downstream mixing of regional microbiotas. The downstream mixing of regional microbiotas was also responsible for the majority of observed co-occurrence patterns among microbial families. Our results indicate that fecal and cloacal samples inadequately represent the complex patterns of richness, composition, and variability of the gut microbiota and obscure patterns of co-occurrence of microbial lineages.

Understanding how ecological communities are organized and how they change through time is critical to predicting the effects of climate change. Recent work documenting the co-occurrence structure of modern communities found that most significant species pairs co-occur less frequently than would be expected by chance. However, little is known about how co-occurrence structure changes through time. Here we evaluate changes in plant and animal community organization over geological time by quantifying the co-occurrence structure of 359,896 unique taxon pairs in 80 assemblages spanning the past 300 million years. Co-occurrences of most taxon pairs were statistically random, but a significant fraction were spatially aggregated or segregated. Aggregated pairs dominated from the Carboniferous period (307 million years ago) to the early Holocene epoch (11,700 years before present), when there was a pronounced shift to more segregated pairs, a trend that continues in modern assemblages. The shift began during the Holocene and coincided with increasing human population size and the spread of agriculture in North America. Before the shift, an average of 64% of significant pairs were aggregated; after the shift, the average dropped to 37%. The organization of modern and late Holocene plant and animal assemblages differs fundamentally from that of assemblages over the past 300 million years that predate the large-scale impacts of humans. Our results suggest that the rules governing the assembly of communities have recently been changed by human activity.

Ecologists and biogeographers usually rely on a single phylogenetic tree to study evolutionary processes that affect macroecological patterns. This approach ignores the fact that each phylogenetic tree is a hypothesis about the evolutionary history of a clade, and cannot be directly observed in nature. Also, trees often leave out many extant species, or include missing species as polytomies because of a lack of information on the relationship among taxa. Still, researchers usually do not quantify the effects of phylogenetic uncertainty in ecological analyses. We propose here a novel analytical strategy to maximize the use of incomplete phylogenetic information, while simultaneously accounting for several sources of phylogenetic uncertainty that may distort statistical inferences about evolutionary processes. We illustrate the approach using a clade-wide analysis of the hummingbirds, evaluating how different sources of uncertainty affect several phylogenetic comparative analyses of trait evolution and biogeographic patterns. Although no statistical approximation can fully substitute for a complete and robust phylogeny, the method we describe and illustrate enables researchers to broaden the number of clades for which studies informed by evolutionary relationships are possible, while allowing the estimation and control of statistical error that arises from phylogenetic uncertainty. Software tools to carry out the necessary computations are offered.

The endemic hummingbirds Trochilus polytmus and T. scitulus hybridize in a narrow zone of secondary contact in eastern Jamaica. The cline in bill width across the hybrid zone represents the steepest morphological gradient documented thus far in avian biology. Hindlimb size and skeletal proxies for core body size, however, exhibit incongruent patterns of variation across the same transect. Significant correlation between bill width and skull width indicates that genetic loci that affect bill width have pleiotropic effects on cranial morphology posterior of the craniofacial hinge. This study is the first direct examination of skeletal size variation across an avian hybrid zone.

The turkey vulture (Cathartes aura) is a widespread, scavenging species in the Western Hemisphere that locates carrion by smell. Scent guided foraging is associated with an expansion of the olfactory bulbs of the brain in vertebrates, but no such neuroanatomical data exists for vultures. We provide the first measurements of turkey vulture brains, including the size of their olfactory bulbs and numbers of mitral cells, which provide the primary output of the olfactory bulbs. Comparative analyses show that the turkey vulture has olfactory bulbs that are 4× larger and contain twice as many mitral cells as those of the sympatric black vulture (Coragyps atratus), despite having brains that are 20% smaller. The turkey vulture has the largest olfactory bulbs in absolute terms and adjusted for brain size among birds, but the number of mitral cells is proportional to the size of their olfactory bulbs. The combination of large olfactory bulbs, high mitral cell counts and a greatly enlarged nasal cavity likely reflects a highly sensitive olfactory system. We suggest that this sensitive sense of smell allowed the turkey vulture to colonize biomes that are suboptimal for scavenging birds and become the most widespread vulture species in the world.

BackgroundVultures have adapted the remarkable ability to feed on carcasses that may contain microorganisms that would be pathogenic to most other animals. The holobiont concept suggests that the genetic basis of such adaptation may not only lie within their genomes, but additionally in their associated microbes. To explore this, we generated shotgun DNA sequencing datasets of the facial and gut microbiomes from the black and turkey vultures. We characterizedi) the functional potential and taxonomic diversity of their microbiomes,ii) the potential pathogenic challenges they face, and iii) elements in the microbiome that could play a protective role to the vulture’s face and gut.ResultsWe found elements involved in diseases, such as periodontitis and pneumonia (more abundant in the face), and gas gangrene and food poisoning (more abundant in the gut). Interestingly, we found taxa and functions with potential for playing health beneficial roles, such as antilisterial bacteria in the gut, and genes for the production of antiparasites and antiinsectisides in the face. Based on the identified phages, we suggest that phages aid in the control, and possibly elimination as in phage therapy, of microbes reported as pathogenic to a variety of species. Interestingly, we also identifiedAdineta vagain the gut, an invertebrate that feeds on dead bacteria and protozoans, suggesting a defensive predatory mechanism. Finally, we suggest a colonization resistance role though biofilm formation played byFusobacteriaandClostridiain the gut.ConclusionsOur results highlight the importance of complementing genomic analyses with metagenomics in order to obtain a clearer understanding of the host-microbial alliance and show the importance of microbiome-mediated health protection for adaptation to extreme diets, such as scavenging.

Organizational structure for the proposed IsoBank. A central executive group would oversee four subcommittees (SC): Information technology, integrative disciplinary, education and training, and analytical expertise. GNIP, Global Network of Isotopes in Precipitation; IAEA, International Atomic Energy Association; QA/QC, quality assurance/quality control.

To determine whether stable isotopes can be used for identifying the geographic origins of migratory bird populations, we examined the isotopic composition of hydrogen (deuterium, δD), carbon (δ13C), and strontium (δ87Sr) in tissues of a migratory passerine, the black-throated blue warbler (Dendroica caerulescens), throughout its breeding range in eastern North America. δD and δ13C values in feathers, which are grown in the breeding area, varied systematically along a latitudinal gradient, being highest in samples from the southern end of the species’ breeding range in Georgia and lowest in southern Canada. In addition, δD decreased from east to west across the northern part of the breeding range, from New Brunswick to Michigan. δ87Sr ratios were highest in the Appalachian Mountains, and decreased towards the west. These patterns are consistent with geographical variation in the isotopic composition of the natural environment, i.e., with that of precipitation, plants, and soils for δD, δ13C, and δ87Sr, respectively. Preliminary analyses of the δD and δ13C composition of feathers collected from warblers in their Caribbean winter grounds indicate that these individuals were mostly from northern breeding populations. Furthermore, variances in isotope ratios in samples from local areas in winter tended to be larger than those in summer, suggesting that individuals from different breeding localities may mix in winter habitats. These isotope markers, therefore, have the potential for locating the breeding origins of migratory species on their winter areas, for quantifying the degree of mixing of breeding populations on migratory and wintering sites, and for documenting other aspects of the population structure migratory animals – information needed for studies of year-round ecology of these species as well as for their conservation. Combining information from several stable isotopes will help to increase the resolution for determining the geographic origins of individuals in such highly vagile populations.

International audience; To better determine the history of modern birds, we performed a genome-scale phylogenetic analysis of 48 species representing all orders of Neoaves using phylogenomic methods created to handle genome-scale data. We recovered a highly resolved tree that confirms previously controversial sister or close relationships. We identified the first divergence in Neoaves, two groups we named Passerea and Columbea, representing independent lineages of diverse and convergently evolved land and water bird species. Among Passerea, we infer the common ancestor of core landbirds to have been an apex predator and confirm independent gains of vocal learning. Among Columbea, we identify pigeons and flamingoes as belonging to sister clades. Even with whole genomes, some of the earliest branches in Neoaves proved challenging to resolve, which was best explained by massive protein-coding sequence convergence and high levels of incomplete lineage sorting that occurred during a rapid radiation after the Cretaceous-Paleogene mass extinction event about 66 million years ago.

SummarySwainson’s WarblerLimnothlypis swainsoniiis a secretive species of high conservation concern with an estimated global breeding population of 90,000 individuals sparsely distributed across 15 states in the south-eastern United States. Its status as one of the rarest songbirds in North America has been attributed to the scarcity of breeding and wintering habitat. Although the warbler was once thought to be a habitat specialist of lowland canebrakes, it is now known to breed in a wide spectrum of broadleaf forest habitats linked by the common denominator of high stem densities and visual screening in the understorey stratum. Scattered instances of a fundamental habitat expansion into early seral stages of even-aged pine plantations were first observed in east Texas in 1992. Here I report that the colonisation of pine plantations is not only locally extensive in Texas but that it is widespread on the coastal plain eastward to south-eastern Virginia. During two decades of field surveys, breeding territories (n =297) were documented in young pine plantations in 95 counties and parishes in 10 states. Occupied plantations were mostly 6–12 m tall (median = 7.5 m), corresponding to 8–15 years after planting. Soil type and the presence of interspersed broadleaf vegetation may be important co-factors in plantation occupancy. The chronology of this breeding niche expansion is poorly known but it appears to have occurred after the 1970s, most likely catalysed by the rapid growth of pine plantation silviculture after World War II. As late as 2001, it was believed that > 90% of the breeding population occurred in broadleaf floodplain forest. The recent range-wide colonisation of pine plantations changes the calculus. If the current trend continues, forest lands managed for short-rotation pine plantations will support the majority of breeding populations by the end of the 21stcentury.

Sphyrapicus varius (Yellow-bellied Sapsucker) has been reported drilling sap wells in more than 250 species of trees and woody vines in eastern North America. Criteria for species selection and use of geographically restricted endemics are poorly understood. Here I report drilling frequencies in Cotinus obovatus (American Smoketree), a rare endemic whose center of abundance occurs in the wintering range of Yellow-bellied Sapsuckers in the Ozark Mountains. Horizontal bands of sap wells were present on 4.5% of specimens (DBH ≥ 7 cm; n = 402) and 12.1% of larger-diameter classes (DBH ≥ 20 cm; n = 149). Sapsuckers preferred larger trees exhibiting little cambial dieback. Latticed arrays of sap wells similar to those observed on breeding territories were present on several large specimens. This survey indicates that the Yellow-bellied Sapsucker exploits rare species that may only be encountered on their winter territories. Documentation of a yearling inspecting a preexisting array of sap wells suggests that yearlings may obtain cues for appropriate tree species selection by examining sapsucker drillings encountered on wintering grounds. Because sap wells persist for years, cultural transmission of sapping information is likely transgenerational.

Heat-stressed New World vultures (Cathartidae) practice urohidrosis by excreting urate-rich urine on their tarsi and feet to decrease body temperature through evaporative cooling. Soft par...

Vultures are highly reliant on their sensory systems for the rapid detection and localization of carrion before other scavengers can exploit the resource. In this study, we compared eye morphology and retinal topography in two species of New World vultures (Cathartidae), turkey vultures (Cathartes aura), with a highly developed olfactory sense, and black vultures (Coragyps atratus), with a less developed sense of olfaction. We found that eye size relative to body mass was the same in both species, but that black vultures have larger corneas relative to eye size than turkey vultures. However, the overall retinal topography, the total number of cells in the retinal ganglion cell layer, peak and average cell densities, cell soma area frequency distributions, and the theoretical peak anatomical spatial resolving power were the same in both species. This suggests that the visual systems of these two species are similar and that vision plays an equally important role in the biology of both species, despite the apparently greater reliance on olfaction for finding carrion in turkey vultures.

SummaryThe endemic Jamaican subspecies of the Golden SwallowTachycineta euchrysea euchryseahas been rare and locally distributed since its discovery in 1847. By the 1950s, its geographic range had contracted to a small region along the northern frontier of Cockpit Country. The last unequivocal sight records occurred in the early 1980s, raising strong concern about the swallow’s conservation status. I conducted an island-wide search for the swallow from 1994 through 2012. Standardised censuses of aerial insectivores at 1,281 sites, including the last redoubts of the Golden Swallow in Trelawny Parish, revealed no evidence of the species. These surveys and the absence of documented sight records during the past three decades suggest that the Jamaican race of the Golden Swallow is close to extinction if not already extinct. The cause of the population decline is unknown but is most likely linked to chronic predation by introduced mammalian predators, particularly the arboreal black ratRattus rattus.

Next-Generation Biogeography In 1876, Alfred Russel Wallace mapped the zoogeographical regions of the world, based on the distributions and taxonomic relationships of broadly defined mammalian families. Wallace's classification of zoogeographical regions became a cornerstone of modern biogeography and a reference for a wide variety of biological disciplines, including global biodiversity and conservation sciences. Holt et al. (p. 74 , published online 20 December) present a next-generation map of wallacean zoogeographic regions, incorporating phylogenetic data on >20,000 vertebrate species to discern and characterize their natural biogeographic patterns.

Summary The regal moth (Citheronia regalis F.; Lepidoptera: Saturniidae) is reported for the first time feeding on foliage of the American smoketree (Cotinus obovatus Raf.; Anacardiaceae), an endemic tree with a relictual distribution on calcareous soils in the southern United States. This record constitutes the third lepidopteran species known to feed on this rare tree in a natural setting.