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Ambient noise can cause birds to adjust their songs to avoid masking. Most studies investigate responses to a single noise source (e.g., low-frequency traffic noise, or high-frequency insect noise). Here, we investigated the effects of both anthropogenic and insect noise on vocalizations of four common bird species in Hong Kong. Common Tailorbirds (Orthotomus sutorius) and Eurasian Tree Sparrows (Passer montanus) both sang at a higher frequency in urban areas compared to peri-urban areas. Red-whiskered Bulbuls (Pycnonotus jocosus) in urban areas shifted the only first note of their song upwards. Swinhoe’s White-eye (Zosterops simplex) vocalization changes were correlated with noise level, but did not differ between the peri-urban and urban populations. Insect noise caused the Eurasian Tree Sparrow to reduce both maximum, peak frequency, and overall bandwidth of vocalizations. Insect noise also led to a reduction in maximum frequency in Red-whiskered bulbuls. The presence of both urban noise and insect noise affected the sound of the Common Tailorbirds and Eurasian Tree Sparrows; in urban areas, they no longer increased their minimum song frequency when insect sounds were also present. These results highlight the complexity of the soundscape in urban areas. The presence of both high- and low-frequency ambient noise may make it difficult for urban birds to avoid signal masking while still maintaining their fitness in noisy cities., Studies have shown that birds increase their vocalization pitch under low-frequency urban noise and sing at a lower pitch when exposed to high-frequency insect sounds, but what if they occur simultaneously? Using field recordings, we found that some urban birds no longer adjusted their song in response to urban noise when insect noise is also present. This shows that anthropogenic noise is not the only driver of changes in urban bird songs.

A new feather mite genus Bernierinyssus gen. n. (Analgoidea: Pteronyssidae), associated with endemic Malagasy warblers (Passeriformes: Bernieridae), is proposed based on morphological evidence and DNA sequence data. Within this genus, we detected six mite species, including five new species described here: Bernierinyssus angulatus sp. n. from Crossleyia xanthophrys, B. bernieriae sp. n. from Bernieria madagascariensis, B. bifenestratus sp. n. from Hartertula flavoviridis, B. randiae sp. n. from Randia pseudozosterops, B. xanthomixis sp. n. from Xanthomixis zosterops (type host) and X. cinereiceps, and B. oxylabis (Mironov and Wauthy 2005) comb. n. (transferred from Pteronyssoides Hull). Phylogenetic relationships of these mites were nearly perfectly congruent with those of their hosts, indicating that ancestral Bernierinyssus probably co-dispersed to Madagascar on the common ancestor of Malagasy warblers and then cospeciated with their hosts. Species of Bernierinyssus are well-delimited based on several lines of evidence: morphology (clear among-specific differences in discrete characters), host associations (one mite species per one host species, except for B. xanthomixis), genetic distances (large COX1 barcoding gap between among- and within-species K2P distances: 8.22¨C12.38% vs 0¨C2.9%, respectively), and molecular phylogenetics (all species are well-supported, monophyletic clades). Our study suggests that species of the genus Bernierinyssus have evolved slower than their avian hosts or co-associated feather lice. Despite the discordance in the mitochondrial DNA evolutionary rates, speciation events in mites largely corresponded to bird species divergences, resulting in a nearly perfect correlation between mite and bird species richness (Eichler's Rule). The mite B. xanthomixis was associated with two avian species, but still formed two distinct shallow lineages (COX1 distance: 1.65%) separated by the host species. The nearly strict host-specificity pattern found in Bernierinyssus contrasts with that of continental feather mites, which tend to be less host-specific and have nearly equal proportions of single-host vs multi-host species.

Aim: Variation in species diversity among different geographical areas may result from differences in speciation and extinction rates, immigration and time for diversification. An area with high species diversity may be the result of a high net diversification rate, multiple immigration events from adjacent regions, and a long time available for the accumulation of species (known as the 'time-for-speciation effect'). Here, we examine the relative importance of the three aforementioned processes in shaping the geographical diversity patterns of a large radiation of passerine birds.Location: Global.Taxon: Babblers (Aves: Passeriformes).Methods: Using a comprehensive phylogeny of extant species (similar to 90% sampled) and distributions of the world's babblers, we reconstructed their biogeographical history and analysed the diversification dynamics. We examined how species richness correlates with the timing of regional colonization, the number of immigration events and the rate of speciation within all 13 geographical distribution regions.Results: We found that babblers likely originated in the Sino-Himalayan Mountains (SHM) in the early Miocene, suggesting a long time for diversification and species accumulation within the SHM. Regression analyses showed the regional diversity of babblers can be well explained by the timing of the first colonization within of these areas, while differences in rates of speciation or immigration have far weaker effects. Nonetheless, the rapid speciation of Zosterops during the Pleistocene has accounted for the increased diversification and accumulation of species in the oceanic islands.Main Conclusions: Our results suggest that the global diversity patterns of babblers have predominantly been shaped by the time-for-speciation effect. Our findings also support an origin centred in tropical and subtropical parts of the SHM, with a cradle of recent diversification in the oceanic islands of the Indo-Pacific and Indian Ocean regions, which provides new insights into the generation of global biodiversity hotspots.

Because a population’s ability to respond to rapid change is dictated by standing genetic variation, we can better predict a population’s long-term viability by estimating and then comparing adult census size (N) and effective population size (N(e)). However, most studies only measure N or N(e), which can be misleading. Using a combination of field and genomic sequence data, we here estimate and compare N and N(e) in two range-restricted endemics of the Solomon Islands. Two Zosterops White-eye species inhabit the small island of Kolombangara, with a high elevation species endemic to the island (Z. murphyi) and a low elevation species endemic to the Solomon Islands (Z. kulambangrae). Field observations reveal large values of N for both species with Z. kulambangrae numbering at 114,781 ± 32,233 adults, and Z. murphyi numbering at 64,412 ± 15,324 adults. In contrast, genomic analyses reveal that N(e) was much lower than N, with Z. kulambangrae estimated at 694.5 and Z. murphyi at 796.1 individuals. Further, positive Tajima’s D values for both species suggest that they have experienced a demographic contraction, providing a mechanism for low values of N(e). Comparison of N and N(e) suggests that Z. kulambangrae and Z. murphyi are not at immediate threat of extinction but may be at genetic risk. Our results provide important baseline data for long-term monitoring of these island endemics, and argue for measuring both population size estimates to better gauge long-term population viability.

Southern Africa is remarkably rich in avian species diversity, however, the evolutionary and biogeographic mechanisms responsible for that diversity are, in general, poorly understood, and this is particularly true with respect to the many species that are endemic or near-endemic to the region. Here, we used mtDNA to assess genetic structure in three southern African bird species to determine whether each was genetically panmictic, or whether there was standing genetic variation upon which abiotic factors (e.g., climate, biome boundaries, geographic features) could have acted to drive lineage diversification. Haplotype diversity was partitioned into two (two species) or three (one species) distinct haplotype clusters that did not reflect biogeographic or biome partitioning, instead, haplotype clusters overlapped in central South Africa. Population and demographic analyses, along with ecological niche modeling and Bayesian Skyline Plots, indicated that each of the three species were likely isolated in refugia during Pleistocene climatic perturbations, with subsequent expansions from refugia resulting in present-day overlapping distributions. Collectively, our analyses suggest that an ephemeral speciation model is operating in southern Africa, driven by the dynamic climatic oscillations that characterize the region. At least some of the regional endemic bird species (e.g., White-eyes, Zosterops spp.) may be the result of sufficiently long periods in refugia as opposed to the distinct but ephemeral clusters recovered within our three focal species.

ACKNOWLEDGEMENTS J.O.E. and L.L. coordinated and secured project funding with the support from J.S.C.; we thank AT Peterson and CH Graham and two reviewers for critical feedback on earlier stages of the manuscript. The project was funded by the Research Foundation – Flanders (FWO; 1527918N & G042318N). J.O.E. received additional funds by an FWO Postdoctoral Fellowship (12G4317N). The authors declare no conflict of interest. No permits were needed to conduct the re- search presented here. DATA AVAILABILITY STATEMENT All data are available from open source platforms. Raw GBIF.org occurrence data used for this work (as accessed on 21st October 2016) can be accessed through GBIF Occurrence Download http://doi.org/10.15468/dl.erwqs6. We have deposited the prepared data used for this work on FigShare accessible through https://doi.org/10.6084/m9.figshare.13042031.v1 as well as R scripts for data analysis in a GitHub repository accessible through https://github.com/JOEngler/ZostiNicheEvol.

Aim Morphological and lineage evolution are predicted to follow different patterns in island and mainland radiations. However, the extent to which these geographical contexts influence evolutionary trajectories remains poorly understood, in part because few studies have focused on species‐rich clades colonizing continents and archipelagos over comparable timeframes. Focusing on a diverse songbird clade radiating on the African continent and adjacent islands, we tested whether morphological evolution is best explained by adaptive or non‐adaptive processes, and whether mainland and island lineages evolved to occupy different regions or volumes of morphological space (morphospace). Location Palaeotropics, with a particular focus on the Afrotropical region. Taxon White‐eyes, Zosterops (Aves: Zosteropidae). Methods We generated principal component axes from novel trait data for 120 species and combined this information with a comprehensive dated phylogeny. We then analysed the dynamics of trait and lineage diversification using comparative evolutionary methods. Results An early burst and slowdown pattern of lineage accumulation is not mirrored by phenotypic evolution, which instead shows an apparent convergence on particular phenotypes. However, the overall signature of phenotypic convergence is strongly driven by mainland taxa, in which phenotypes appear to be highly constrained within elevational zones, while speciation events are often associated with phenotypic divergence from one body plan to the other after colonization of highland from lowland habitats, or vice versa. By contrast, island lineages have repeatedly explored novel areas of morphospace with patterns of phenotypic divergence generally not distinguishable from a random‐walk model. Main conclusions Diversification of Zosterops highlights contrasting evolutionary trends and dynamics for continental versus island species. We suggest the different trajectory of evolution in insular lineages arises from reduced species competition leading to an increase in ecological opportunity, thereby providing a release to phenotypic constraints experienced by continental taxa.

China has a history and reputation of substantial exploitation of wildlife, and the harvest and trade of wild birds are common throughout the country, both for exportation and local demand. This study documents the diversity and quantity of birds being traded in the city of Guiyang, Southwest China, and evaluates its potential conservation effects. Data were collected through direct observations and through informal conversations on weekends in a public market between March 2014 and February 2015. In total, 206 species belonging to 40 families and 13 orders were recorded, with the family Turdidae having the largest species diversity observed (28 species). The number of individuals on sale was greatly variable among different species. Ashy-throated parrotbills (Paradoxornis alphonsianus) were the most encountered birds, mainly driven by the practice of bird fighting, followed by Acridotheres cristatellus, Garrulax canornus, Zosterops japonicas, Zosterops palpebrosa, Zosterops erythropleurus, Rhyacornis fuliginosus, Emberiza elegans, Leiothrix lutea and Phoenicurus auroreus, which are all common and native to Guiyang. Our data indicated that at least 2000 individuals have been traded in one year for each of these species. We argue that the current bird trade raises a serious potential threat of over-exploitation of these species, especially due to bird fighting and hunting during the breeding season, as well as raising further potential threats of invasive species spread and disease transmission. Measures to control the trade are discussed here, and environmental education could be the most effective. This study highlights the significance of paying more attention to the domestic bird trade in the subtropical region.

White-eyes (Zosterops) are a hyper-diverse genus of passerine birds that have rapidly radiated across the Afrotropics and Southeast Asia. Despite their broad range, a disproportionately large number of species are currently recognised from islands compared to the mainland. Described species-level diversity of this ‘great speciator’ from continental Africa-Arabia is strikingly low, despite the vast size and environmental complexity of this region. However, efforts to identify natural groups using traditional approaches have been hindered by the remarkably uniform morphology and plumage of these birds. Here, we investigated the phylogenetic relationships and systematics of Afrotropical Zosterops, including the Gulf of Guinea and western Indian Ocean islands. We included exceptional sampling (~160 individuals) from all except one subspecies of the 55 taxa (32 species, plus 23 additional named sub-species) currently recognized throughout the region, in addition to a subset of extra-Afrotropical taxa, by exploiting blood and archival samples. Employing a multi-locus phylogenetic approach and applying quantitative species delimitation we tested: (1) if there has been a single colonisation event of the Afrotropical realm; (2) if constituent mainland and island birds are monophyletic; and (3) if mainland diversity has been underestimated. Our comprehensive regional phylogeny revealed a single recent colonisation of the Afrotropical realm c.1.30 Ma from Asia, but a subsequent complex colonisation history between constituent island and mainland lineages during their radiation across this vast area. Our findings suggest a significant previous underestimation of continental species diversity and, based on this, we propose a revised taxonomy. Our study highlights the need to densely sample species diversity across ranges, providing key findings for future conservation assessments and establishing a robust framework for evolutionary studies.

The presence of congeneric taxa on the same island suggests the possibilityofin situdivergence, but can also result from multiple colonizations of pre-viously diverged lineages. Here, using genome-wide data from a largepopulation sample, we test the hypothesis that intra-island divergenceexplains the occurrence of four geographical forms meeting at hybridzones in the Reunion grey white-eye (Zosterops borbonicus), a species complexendemic to the small volcanic island of Reunion. Using population genomicand phylogenetic analyses, we reconstructed the population history of thedifferent forms. We confirmed the monophyly of the complex and foundthat one of the lowland forms is paraphyletic and basal relative to others,a pattern highly consistent within situdivergence. Our results suggest initialcolonization of the island through the lowlands, followed by expansion intothe highlands, which led to the evolution of a distinct geographical form,genetically and ecologically different from the lowland ones. Lowlandforms seem to have experienced periods of geographical isolation, butthey diverged from one another by sexual selection rather than nichechange. Overall, low dispersal capabilities in this island bird combinedwith both geographical and ecological opportunities seem to explain howdivergence occurred at such a small spatial scale., This work was supported by the Fonds Inkerman, the Agence Française pour le Développement, the National Geographic Society, the Fondation pour la Recherche sur la Biodiversité, the ‘Laboratoired’ Excellence’TULIP (ANR-10-LABX-41), ANR grant (BirdIslandGe-nomic project, ANR-14-CE02-0002) to B.N., and a PhD studentshipfrom the Ministère de l’Enseignement Supérieur et de la Recherche to M.G

The merger of formerly isolated lineages is hypothesized to occur in vertebrates under certain conditions. However, despite many demonstrated instances of introgression between taxa in secondary contact, examples of lineage mergers are rare. Preliminary mtDNA sequencing of a Malagasy passerine, Xanthomixis zosterops (Passeriformes: Bernieridae), indicated a possible instance of merging lineages. We tested the hypothesis that X. zosterops lineages are merging by comparing mtDNA sequence and microsatellite data, as well as mtDNA sequence data from host-specific feather lice in the genus Myrsidea (Phthiraptera: Menoponidae). Xanthomixis zosterops comprises four deeply divergent, broadly sympatric, cryptic mtDNA clades that likely began diverging approximately 3.6 million years ago. Despite this level of divergence, the microsatellite data indicate that the X. zosterops mtDNA clades are virtually panmictic. Three major phylogroups of Myrsidea were found, supporting previous allopatry of the X. zosterops clades. In combination, the datasets from X. zosterops and its Myrsidea document a potential merger of previously allopatric lineages that likely date to the Pliocene. This represents the first report of sympatric apparent hybridization among more than two terrestrial vertebrate lineages. Further, the mtDNA phylogeographic pattern of X. zosterops, namely the syntopy of more than two deeply divergent cryptic clades, appears to be a novel scenario among vertebrates. We highlight the value of gathering multiple types of data in phylogeographic studies to contribute to the study of vertebrate speciation.

Patterns of phenotypic and genic frequencies across hybrid zones provide insight into the origin and evolution of reproductive isolation. The Reunion grey white‐eye, Zosterops borbonicus, exhibits parapatrically distributed plumage colour forms across the lowlands of the small volcanic island of Reunion (Mascarene archipelago). These forms meet and hybridize in regions that are natural barriers to dispersal (rivers, lava fields). Here, we investigated the relationship among patterns of differentiation at neutral genetic (microsatellite) markers, phenotypic traits (morphology and plumage colour) and niche characteristics across three independent hybrid zones. Patterns of phenotypic divergence revealed that these hybrid zones are among the narrowest ever documented in birds. However, the levels of phenotypic divergence stand in stark contrast to the lack of clear population neutral genetic structure between forms. The position of the hybrid zones coincides with different natural physical barriers, yet is not associated with steep changes in vegetation and related climatic variables, and major habitat transitions are shifted from these locations by at least 18 km. This suggests that the hybrid zones are stabilized over natural dispersal barriers, independently of environmental boundaries, and are not associated with niche divergence. A striking feature of these hybrid zones is the very low levels of genetic differentiation in neutral markers between forms, suggesting that phenotypic divergence has a narrow genetic basis and may reflect recent divergence at a few linked genes under strong selection, with a possible role for assortative mating in keeping these forms apart., The first author was supported by a MESR (Ministère de l'Enseignement Supérieur et de la Recherche) PhD scholarship during this study. The work was funded by Agence Française pour le Développement, a National Geographic Society Grant, Fondation pour la Recherche sur la Biodiversité (FRB), the ‘Laboratoire d'Excellence’ TULIP (ANR‐10‐LABX‐41) and the SYNTHESYS Project (http://www.synthesys.info/) which was financed by European Community Research Infrastructure Action under the FP7 ‘Capacities’ Programme at the Museo Nacional de Ciencias Naturales (CSIC) in Madrid, Spain.

The Spectacled Tetraka Xanthomixis zosterops is a sexually monomorphic species in a family (Bernieridae) endemic to Madagascar and is found in various humid forest types. It is categorised as Least Concern by the IUCN. Despite its commonness, the biology of this species is little known. This study focused on its breeding biology and took place from September to December 2010 at Talatakely, Ranomafana National Park, Madagascar. Thirty nests were monitored and incubating birds were marked. Direct observations were made associated with nest building, incubating and nestling periods. Habitat structure was assessed to detect nesting site choice. The breeding episode, from the nest-building stage to fledging of the last chick, lasted on average 45 d. Only one individual, probably the female, in each presumed pair incubated eggs and brooded hatchlings, whereas both parents fed and cared for the nestlings. The mean clutch size was 2.4 ± 0.2 egg per nest (range 1–3, n = 24), the incubation period averaged 17.7 ± 0...

Aim Niche modelling is increasingly used to predict species' geographical dis- tributions or to infer the evolutionary or ecological processes that constrain them, but relatively few studies have examined the ecological processes govern- ing the distributions of parasites. Among such processes, niche divergence is frequently invoked to explain species range variation. Here, we test whether the geographical distributions of two lineages of Leucocytozoon (Haemosporida) avian parasites are linked to climatic conditions and whether niche divergence can explain their geographical separation. Location Reunion, Mascarene archipelago, south-western Indian Ocean. Methods Leucocytozoon prevalence data were obtained by PCR screening of avian blood samples. Prevalence data and 20 environmental layers were used to build species distribution models (SDMs). SDMs were built by averaging the predictions of five different models: random forests (RF), generalized linear models (GLM), generalized additive models (GAM), multivariate adaptive regression splines (MARS) and support vector machines (SVM). Niche identity and background tests were used to test for a role of niche divergence in explaining parasite distributions. Results The geographical ranges of the two lineages of Leucocytozoon under study showed little overlap. Species distribution modelling suggested that niche divergence may explain the spatial variation observed in Leucocytozoon distribu- tion, implying that the geographical separation of parasites is linked to envi- ronmental conditions. The variables that best explained parasite distribution were all related to precipitation patterns. Main conclusions As precipitation cannot directly affect endosymbiotic Leuc- ocytozoon parasites, we suggest that the geographical separation of Leucocytozo- on lineages is the result of an underlying geographical structure in the dipteran vectors that transmit these parasites. This illustrates the need to consider the ecology of vectors when predicting the distribution of vector-borne parasites. Our study also shows that different parasite lineages, contained within broadly defined parasitic taxa, may have very different ecologies, and that these differ- ences should be taken into account when attempting to understand the ecolog- ical determinants of parasite distribution and disease emergence.

1. Patterns of pathogen co-occurrence can affect the spread or severity of disease. Yet due to difficulties distinguishing and interpreting co-infections, evidence for the presence and directionality of pathogen co-occurrences in wild hosts is rudimentary. 2. We provide empirical evidence for pathogen co-occurrences by analysing infection matrices for avian malaria (Haemoproteus and Plasmodiumspp.) and parasitic filarial nematodes (microfilariae) inwild birds (New Caledonian Zosteropsspp.). 3. Using visual and genus-specific molecular parasite screening, we identified high levels of co-infections that would have been missed using PCR alone. Avian malaria lineages were assigned to species level using morphological descriptions. We estimated parasite co-occurrence probabilities, while accounting for environmental predictors, in a hierarchical multivariate logistic regression. 4. Co-infections occurred in 36% of infected birds. Weidentified both positive and negatively correlated parasite co-occurrence probabilities when accounting for host, habitat and island effects. Two of three pairwise avian malaria co-occurrences were strongly negative, despite each malaria parasite occurring across all islands and habitats. Birds with microfilariae had elevated heterophil to lymphocyte ratios and were all co-infected with avian malaria, consistent with evidence that host immune modulation by parasitic nematodes facilitates malaria co-infections. Importantly, co-occurrence patterns with microfilariae varied in direction among avian malaria species; two malaria parasites correlated positively but a third correlated negatively with microfilariae. 5. We show that wildlife co-infections are frequent, possibly affecting infection rates through competition or facilitation. We arguethat combining multiple diagnostic screening methods with multivariate logistic regression offers a platform to disentangle impacts of environmental factors and parasite co-occurrences on wildlife disease.

Members of the genus Zosterops are known for their colonizing ability and extensive phenotypic differentiation on numerous islands. There have been morphological and biochemical analyses of some Zosterops populations, but little study has been devoted to patterns of vocal communication signals, known to be important pre-mating barriers in many bird species and in possible diversification of taxa. I report on the song system of one subspecies of Zosterops in a mainland population and an island population 15 km distant. I used both a traditional subjective classification of song elements and the multivariate procedure of linear discriminant analyses (LDA) of measured sound features. The syllables constituting songs exhibited a low level of stereotypy, disallowing a lexicon of syllable ‘types’ to be constructed for individuals or a population. New syllables were continuously produced as a bird uttered more and more songs, possibly indicating an extremely large repertoire or an open-ended generation ...

Geographic relocations of migratory passerines have shown that adults can compensate for physical displacements; juveniles on their first migration, however, use an innate clock-and-compass strategy and are unable to compensate for displacement. We examined the effects of changes in magnetic inclination and intensity on orientation of adult and juvenile Australian Silvereyes (Zosterops l. lateralis) to learn if geomagnetic cues are used by a migratory passerine for geographic positioning. Silvereyes, captured in breeding areas in Tasmania, were physically transported to a location along their migratory route and assessed for orientation during autumn migration. Adults and juveniles exhibited seasonally appropriate, northeasterly orientation (19° and 23° east of magnetic North, respectively) when tested under the natural geomagnetic field. Birds were then exposed to changes in the magnetic field that simulated either southern (SimS) or northern (SimN) locations near the beginning and end, respecti...

Parasite communities on islands are assembled through multiple immigrations and ⁄or in-situ diversification. In this study, we used a phylogenetic approach to investigate the role of such processes in shaping current patterns of diversity in Leucocytozoon, a group of haemosporidian blood parasites infecting whites eyes (Zosterops) endemic to the Mascarene archipelago (south-western Indian Ocean). We found that this parasite community arose through a combination of multiple immigrations and in-situ diversification, highlighting the importance of both processes in explaining island diversity. Specifically, two highly diverse parasite clades appear to have been present in the Mascarenes for most of their evolutionary history and have diversified within the archipelago, while another lineage apparently immigrated more recently, probably with human-introduced birds. Interestingly, the evolutionary histories of one clade of parasites and Indian Ocean Zosterops seem tightly associated with a significant signal for phylogenetic congruence, suggesting that host–parasite co-divergence may have occurred in this system.

Archipelago-endemic bird radiations are familiar to evolutionary biologists as key illustrations of evolutionary patterns. However, such radiations are in fact rare events. White-eyes (Zosteropidae) are birds with an exceptionally high colonization and speciation potential; they have colonized more islands globally than any other passerine group and include the most species-rich bird genus. The multiplication of white-eye island endemics has been consistently attributed to independent colonizations from the mainland; the white-eyes of the Gulf of Guinea archipelago had been seen as a classic case, spanning as great a breadth of phenotypic diversity as the family worldwide. Contrary to this hypothesis, our molecular phylogenetic analysis places the Gulf of Guinea white-eyes in just two radiations, one grouping all five oceanic island taxa and the other grouping continental island and land-bridge taxa. Numerous ‘aberrant’ phenotypes (traditionally grouped in the genus Speirops) have evolved independently over a short space of time from nonaberrant (Zosterops) phenotypes; the most phenotypically divergent species have separated as recently as 0.22 Ma. These radiations rival those of Darwin’s finches and the Hawaiian honeycreepers in terms of the extent of adaptive radiation per unit time, both in terms of species numbers and in terms of phenotypic diversity. Tempo and patterns of morphological divergence are strongly supportive of an adaptive radiation in the oceanic islands driven by ecological interactions between sympatric white-eyes. Here, very rapid phenotypic evolution mainly affected taxa derived from the youngest wave of colonization, in accordance with the model of asymmetric divergence owing to resource competition in sympatry.

Aim (1) To describe the species–area relationships among communities of Plasmodium and Haemoproteus parasites in different island populations of the same host genus (Aves: Zosterops). (2) To compare distance–decay relationships (turnover) between parasite communities and those with potential avian and dipteran hosts, which differ with respect to their movement and potential to disperse parasite species over large distances. Location Two archipelagos in the south-west Pacific, Vanuatu and New Caledonia (c. 250 km west of Vanuatu) and its Loyalty Islands, with samples collected from a total of 16 islands of varying sizes (328–16,648 km 2 ). Methods We characterized parasite diversity and distribution via polymerase chain reaction (PCR) from avian (Zosterops) blood samples. Bayesian methods were used to reconstruct the parasite phylogeny. In accordance with recent molecular evidence, we treat distinct mitochondrial DNA lineages as equivalent to species in this study. Path analysis and parasite lineage accumulation curves were used to assess the confounding effect of inadequate sampling on the estimation of parasite richness. Species–area and species–distance relationships were assessed using linear regression: distance–decay relationships were assessed using Mantel tests. Results Birds and mosquito species andPlasmodium lineages exhibited significant species–area relationships. However, Plasmodium lineages showed the weakest ‘species–area’ relationship; no relationship was found for Haemoproteus lineages. Avian species richness influenced parasite lineage richness more than mosquito species richness did. Within individual avian host species, the species–area relationship of parasites showed differing patterns. Path analysis indicated that sampling effort was unlikely to have a confounding effect on parasite richness. Distance from mainland (isolation effect) showed no effect on parasite richness. Community similarity decayed significantly with distance for avifauna, mosquito fauna and Plasmodium lineages but not for Haemoproteus lineages. Main conclusions Plasmodium lineages and mosquito species fit the power-law model with steeper slopes than found for the avian hosts. The lack of species– distance relationship in parasites suggests that other factors, such as the competence of specific vectors and habitat features, may be more important than distance. The decay in similarity with distance suggests that the sampled Plasmodium lineages and their potential hosts were not randomly distributed, but rather exhibited spatially predictable patterns. We discuss these results in the context of the effects that parasite generality may have on distribution patterns.

Factors that influence speciation rates among groups of organisms are integral to deciphering macroevolutionary processes; however, they remain poorly understood. Here, we use molecular phylogenetic data and divergence time estimates to reconstruct the pattern and tempo of speciation within a widespread and homogeneous bird family (white-eyes, Zosteropidae) that contains an archetypal “great speciator.” Our analyses show that the majority of this species-rich family constitutes a clade that arose within the last 2 million years, yielding a per-lineage diversification rate among the highest reported for vertebrates (1.95–2.63 species per million years). However, unlike most rapid radiations reported to date, this burst of diversification was not limited in geographic scope, but instead spanned the entire Old World tropics, parts of temperate Asia, and numerous Atlantic, Pacific, and Indian Ocean archipelagos. The tempo and geographic breadth of this rapid radiation defy any single diversification paradigm, but implicate a prominent role for lineage-specific life-history traits (such as rapid evolutionary shifts in dispersal ability) that enabled white-eyes to respond rapidly and persistently to the geographic drivers of diversification.

A new species of white-eye, the Vanikoro White-eye Zosterops gibbsi , is described from the island of Vanikoro ( = Vanikolo) in the Santa Cruz Islands ( = Temotu Province) within the Solomon Islands. It differs from the geographically closest white-eye, the Santa Cruz White-eye Zosterops sanctaecrucis , by a number of features including a much longer bill, and different leg- and eye-ring colour. This is the second bird species endemic to Vanikoro; the neighbouring Nendo Island supports three endemic species. Although the conservation status of this species appears to be secure, the Santa Cruz Islands are very poorly known. Despite supporting several globally threatened species, the Islands at present are not protected by any conservation activity.

Summary A survey was carried out on the prevalence of blood parasites in birds in the Mascarene Islands. Smears from 357 birds of 25 species in 12 families were examined, of which 150 (42%) were found to harbour blood parasites. The most common parasites were Leucocytozoon; a new species, L. zosteropis, is described from the Grey White-eye Zosterops borbonica mauritiana. This parasite was observed in smears from 68 birds of three species: Z. borbonica, Z. chloronothos and Z. olivacea. Other species of Leucocytozoon identified were L. fringillinarum from fodies, sparrows and a bulbul and L. marchouxi from two doves. Haemoproteus was found only in domestic pigeons Columba livia and identified as H. columbae. Plasmodium relictum, P. vaughani and an unidentified species with elongate gametocytes were found in Zosterops, and Plasmodium sp. of low infection observed in other hosts. Trypanosoma mayae is redescribed from the House Sparrow Passer domesticus and the Mauritius Fody Foudia rubra, and considered to be a valid species. A new species of trypanosome, Trypanosoma phedinae, is described from the Malagasy Swallow Phedina b. borbonica. Other birds were found to harbour low infections of unidentified species of trypanosomes. A small number of birds were infected with Atoxoplasma, haemogregarines and Rickettsia-like organisms. An unidentified organism with a predilection for eosinophils was observed in several Mascarene Swiftlets Collocalia francica. The results are discussed in relation to the possible effects of the parasites on the birds of the Mascarene Islands and comparisons made with the results of similar surveys on other Indian Ocean Islands.

Summary Evidence of the inter-breeding of grey-bellied Zosterops (atmorii) and green-bellied (virens) at King William's Town, C.P. is presented. In habitat, behaviour, voice, and breeding biology no differences can be found between them. The roosting and flocking habits are discussed. Whereas both lay blue eggs, only the green-belly (virens) has so far been found to lay white eggs. Incubation periods, ascertained to within a few hours, are mostly between 10 and 11 days. Details are given of the nestling and post-nestling periods. Both insects and fruit are taken and fed to young. Z. pallida on the Orange River is very similar in habits. There is a noticeable difference in tonal quality of voice but the general patterns of the calls are the same.

Summary The four major groupings into which the Zosterops forms of southern African can be arranged have for long been treated by conservative systematists as constituting four discrete species (Z. capensis, Z. pallidus, Z. virens and Z. senegalensis). In a major study, published in 1957, Moreau arrived at the tentative conclusion that in zoo-geographical South Africa Z. cupensis and Z. wirens are clearly conspecific, Z. pallidus is a doubtful monotypic species, and Z. senegalais is a polytypic species of wide continental range, specifically segregated from the foregoing on the basis of a wingltail ratio character, and of juxtaposition without evidence of interbreeding. A new study of the complex problem of Zosterops relationships in South Africa based on a critical study of over 900 specimens examined in the Durban Museum, suggests that only two species (Z. pallidus and Z. senegahsis), very closely related and part of the same superspecies, are actually involved.

Summary. This group is admittedly difficult, not only in distinguishing between the species, especially where, in the majority of specimens, no habitat is given on the labels, but even when this has been done, in distinguishing the recognizable races. Zosterops eurycricotus and Zosterops kikuyuensis are not so difficult if the eye-ring and broad yellow forehead are carefully compared. These two species may be confused with Zosterops virens jacksoni, but the) have a larger eye-ring and a broader and bright yellow forehead. Zosterops senegalensis is variable individually and alters somewhat between fresh and worn specimens, the young bird being rather darker than the adults. This species is always brighter above and clearer yellow below than Zosterops virens and, except for Zosterops S. anderssoni, has a shorter bill and the black at the base of the bill does not extend well up on to thc lores. Zosterops s. anderssoni can be distinguished from Zosterops virens stierlingi by the brighter upper side and the rather clearer yellow below, but the bill is not shorter and the black at the babe of the bill in some specimens extende on to the lores, and these specimens can only be distinguished by very careful comparison of colour in a aeries. With Zoskrops virens the females are generally rather greener above and duller below than the males, and the young bird is even more dull. Zosterops v. jacksoni and Zosterops v. schoana arc quite well defined races, but Zosterops v. stuhlmanni and Zosterops u. sterlingi are very close and can only be dist, inguished one from the other in a series, when a differential general tone of colour is observable and which precludes them being placed as synonyms of each other. We can see no character by which the rows we have placed as synonyms can be recognized. In both Zosterops senpgalemis and Zosterops oirene there is some individual variation. and there is no evidence that there is any seasonal change of dress. The habitats given by collectors for Zosterops senegalensis and Zosterops virens seem to show that both these species inhabit the same type of country, and although it can be said that the former inhabits more open and dryer country, i. e., the open hush, savannahs and gallery forests, there is little doubt that in search of food, and perhaps more especially when in mixed bird parties, both species may be found in the same type of country, and the habitat as given under A and B must be considered as only generally correct and, perhaps, more so in the breeding than the non-breeding season. In view of the confusion that has existed between the species some of the published field notes may be unreliable.

Age-related differences in foraging efficiency and behaviour were investigated in a population of colour-ringed Silvereyes Zosterops lateralis. First-year birds were less efficient foragers than older birds with second-year birds being intermediate. First- and second-year birds had lower success rates than older birds overall, and for most capture techniques and substrates. First-year birds never attempted breeding while about half of the second-year birds and all of the older birds did. Both learning and selection effects may have been involved in causing the age-related differences in foraging behaviour. Foraging skills appear to improve during the first 2 years of life and selection could remove the least efficient foragers from the population in winter when food is short. That second-year birds, some of which had already attempted breeding, were not significantly more efficient foragers than first-year birds suggests that reproduction is not delayed until adult levels of foraging efficiency have been attained.

We encountered white-eyes (Zosterops) that did not match any known species during ornithological field observations in the Togian Islands, Gulf of Tomini, Sulawesi, Indonesia. Subsequently, we collected a specimen and made tape recordings. We consider the Zosterops of the Togian Islands to be a new species that differs most strikingly from the Black-crowned White-eye (Z. atrifrons) in lacking a white eye ring and in soft-part colors. The new species has a somewhat higher-pitched, less modulated song than Z. atrifrons. It seems uncommon and has been encountered only near sea level on three small islands, and it may be best considered Endangered. This brings the number of endemic species in the Togian Islands to two and, under BirdLife International criteria, this island group (which has recently been declared a National Park) now qualifies as an Endemic Bird Area.

Molecular phylogenetic hypotheses of species-rich lineages in regions where geological history can be reliably inferred may provide insights into the scale of processes driving diversification. Here we sample all extant or recently extinct white-eye (Zosterops) taxa of the southwest Indian Ocean, combined with samples from all principal continental lineages. Results support a high dispersal capability, with at least two independent continental sources for white-eyes of the region. An early (within 1.8 million years ago) expansion into the Indian Ocean may have originated either from Asia or Africa; the three resulting lineages show a disparate distribution consistent with considerable extinction following their arrival. Africa is supported as the origin of a later expansion into the region (within 1.2 million years ago). On two islands, a pair of Zosterops species derived from independent immigrations into the Indian Ocean co-occur or may have formerly co-occurred, providing strong support for their origin by double-island colonization rather than within-island (sympatric or microallopatric) speciation. On Mauritius and La Reunion, phylogenetic placement of sympatric white-eyes allow us to rule out a scenario in which independent within-island speciation occurred on both islands; one of the species pairs must have arisen by double colonization, while the other pair is likely to have arisen by the same mechanism. Long-distance immigration therefore appears to be responsible for much of the region's white-eye diversity. Independent immigrations into the region have resulted in lineages with mutually exclusive distributions and it seems likely that competition with congeneric species, rather than arrival frequency, may limit present-day diversity.

Passerine birds living on islands are usually larger than their mainland counterparts, in terms of both body size and bill size. One explanation for this island rule is that shifts in morphology are an adaptation to facilitate ecological niche expansion. In insular passerines, for instance, increased bill size may facilitate generalist foraging because it allows access to a broader range of feeding niches. Here we use morphologically and ecologically divergent races of white-eyes (Zosteropidae) to test three predictions of this explanation: (1) island populations show a wider feeding niche than mainland populations; (2) island-dwelling populations are made up of individual generalists; and (3) within insular populations there is a positive association between size and degree of foraging generalism. Our results provide only partial support for the traditional explanation. In agreement with the core prediction, island populations of white-eye do consistently display a wider feeding niche than comparative mainland populations. However, observations of individually marked birds reveal that island-dwelling individuals are actually more specialized than expected by chance. Additionally, neither large body size nor large bill size are associated with generalist foraging behavior per se. These latter results remained consistent whether we base our tests on natural foraging behavior or on observations at an experimental tree, and whether we use data from single or multiple cohorts. Taken together, our results suggest that generalist foraging and niche expansion are not the full explanation for morphological shifts in island-dwelling white-eyes. Hence, we review briefly five alternative explanations for morphological divergence in insular populations: environmental determination of morphology, reduced predation pressure, physiological optimization, limited dispersal, and intraspecific dominance.

The Reunion grey white-eye, Zosterops borbonicus, a passerine bird endemic to Reunion Island in the Mascarene archipelago, represents an extreme case of microgeographical plumage colour variation in birds, with four distinct colour forms occupying different parts of this small island (2512 km2). To understand whether such population differentiation may reflect low levels of dispersal and gene flow at a very small spatial scale, we examined population structure and gene flow by analysing variation at 11 microsatellite loci among four geographically close localities (

Nestled in the South Pacific archipelago of New Caledonia, the island of Lifou is home to a famous bird. To biologists interested in biodiversity, white-eyes (genus Zosterops) are the masters of spawning diversity. Evolutionary biologists Ernst Mayr and Jared Diamond dubbed the birds the “great speciator.” White-eyes are remarkable for appearing in so many varieties. Their order, the passerines, accounts for half of all the species richness found within birds. Among passerines Zosterops is the most diverse of genera, with about 80 described species found in Africa, Australasia, and the South Pacific islands. The birds excel at colonizing islands. Three sympatric species exist on Lifou, which spans just about 1,200 km2, providing scientists with an ideal study model. “The island is incredible. You arrive and find three endemic species of Zosterops living in the same habitat, which is very unusual,” says Luis Valente, coauthor of a recent study analyzing why white-eyes do so well at speciation. “From an evolutionary biologist’s perspective, it’s a really exciting environment.” Previous work has established that these are rapidly evolving birds, but little has been done to peek at the underlying mechanisms. Valente and colleagues were recently the first to sequence and publish a reference genome of Zosterops. They use it as a model against which they can test hypothesis regarding why white-eyes diversified so abundantly compared with other birds. Their work can be found in the XXXXX issue of Genome Biology Evolution (Cornetti et al. 2015). “The idea is that if we look at these species that have been evolving quite rapidly, we can get perhaps more information about the processes that create biodiversity,” says Valente. Valente and coauthors compared the genomes of the three species endemic to Lifu with each other and then expanded their view to compare the genome of Zoetropes as a whole with the genomes of other bird groups (ones which do not diversify as fast and whose genomes have already been published). “The most interesting thing,” Valente says, “is that all of the results went in the direction that we’d expect.” (Such is not always the case in similar investigations, Valente explains.) The team hypothesized that Zoetropes would have a relatively higher number of substitutions, because the changes in their DNA sequences are very rapid. And so it was. They also found a very high number of gene duplications, implying that there are more new genes being formed in the Zoetropes lineage compared with other birds. They also find many genes under positive selection, indicating that the genome of Zoetropes is quite evolutionarily flexible. “When you think of the theory of how things evolve very rapidly, this is exactly what we find in the genomes of Zoetropes,” says Valente. Valiant cautions the work is preliminary and theoretical, but the idea is, he says, if a species has a genome that is very flexible and changes so that new genes are easily formed or different features of the phenotypes appear (rapidly changing wings, for instance) then this can potentially lead to the formation of new species faster than normal. The work might be preliminary, but it is interesting, says Walter Jetz, an evolutionary biologist who was not involved in the study. He would like to see genomes from other species given the same analytical treatment, but says “the work provides a nice demonstration of the sorts of new insights gained from combining genomic among and within species in an explicit spatial and biogeographic context.” Prior to publishing the results of their analysis, Valente says that they were eager to release the reference genome of silvereyes for others to use. “It’s quite exciting to be able to produce the first genome for Zoestrops,” he says, “because it has been a model system for quite a few years and the genome has been in quite some demand.” Asking questions about how genomic characteristics underpin diversification is primarily a theoretical exercise—one that works at solving a fundamental question in biology. Yet Valente thinks this could also be a useful tool for conservationists intent on preserving biodiversity. Though white-eyes are not endangered the method “could show where the genetic diversity is and which populations are priorities for conservation,” he says. “It’s important information to have, but conservationists generally don’t do it because it is very expensive.” In all likeliness, genomic sequencing will continue to become more accessible in the future, and will help cast light on how biodiversity is generated and maintained. If we understand that, Valente says, “perhaps we can predict what might happen to the equilibrium of species if we disturb habitats. It’s quite a wide fundamental question really.”

Of the six forest-living native passerines of Mauritius, five are largely restricted to native vegetation. These are the Mauritius cuckoo-shrike Coracina typica, Mauritius black bulbul Hypsipetes olivaceus Mascarene paradise flycatcher Terpsiphone bourbonnensis, Mauritius olive white-eye Zosterops chloronothus and Mauritius fody Foudia rubra. Their distributions are concentrated on the escarpment south of the central plateau, and most species are absent from the forests near the east coast. Populations in 1993 were of the order of 100–300 pairs for all five species. Since the last census in 1975, the cuckoo-shrike and black bulbul appear to have at least maintained numbers; the former may have increased its population by expanding its range. The flycatcher, olive white-eye and fody have all declined more seriously than could have been expected from the fraction of their former area of occupancy destroyed. Most species are restricted to a small fraction of the available native habitat, because of nest predation and perhaps also reduced food supply, disease and, in the past, organochlorine pesticide use. Three habitat management strategies applicable to their long-term conservation are introduced.

The Capricorn silvereye (Zosterops lateralis chlorocephalus) is ideally suited to investigating the genetic basis of body size evolution. We have isolated and characterized a set of microsatellite markers for this species. Seven out of 11 loci were polymorphic. The number of alleles detected ranged from two to five and observed heterozygosities between 0.12 and 0.67. One locus, ZL49, was found to be sex-linked. This moderate level of diversity is consistent with that expected in an isolated, island population.

The recent, rapid radiation of Zosteropidae, coupled with their high levels of colonizing ability and phenotypic diversity, makes species delimitation within this family problematic. Given these problems, challenges to establish the mechanisms driving diversity and speciation within this group have arisen. Four morphologically distinct southern African Zosterops taxa, with a contentious taxonomic past, provide such a challenge. Here, supplemented with morphological and environmental analytical techniques, a combination of mitochondrial and nuclear markers were analyzed using Bayesian and Likelihood methods to determine their speciation patterns and to establish the phylogenetic relationships of these four morphologically diverse southern African Zosterops taxa. Nearly all individuals were phenotypically diagnosable, even those individuals collected in areas of contact between taxa. Localities where two or more taxa co-occur appear to possess intermediate environmental characteristics. Initial Bayesian and Likelihood mitochondrial DNA analyses and Bayesian structure analyses of the combined nuclear markers indicated levels of hybridization in areas of sympatry. A combined mtDNA and nuclear DNA analysis and a species tree analysis (with hybrids excluded) placed Z. pallidus as sister to the other southern African taxa, with Z. senegalensis the putative sister taxon to a clade comprising Z. capensis and Z. virens. The grouping of taxon-specific sampling localities and the apparent intermediate nature of birds from areas of sympatry points toward an influence of habitat type and the associated climatic conditions in driving Zosterops diversification in southern Africa.

We recorded the locomotor activity of the partially migratory Tasmanian silvereye, Zosterops l. lateralis, and the nonmigratory mainland silvereye, Z. l. familiaris, continuously over 17 and 15 months, respectively, to identify daily and seasonal patterns. While graphing the data showed several trends, statistical analysis did not reveal a significant difference between subspecies, making this study mainly descriptive in nature. The lack of statistical differentiation was possibly due to the low number of study animals and similarities between them. During the first year in captivity, the Tasmanian birds displayed heightened activity during the migratory periods, which was most likely migratory restlessness. The Tasmanian birds did not show any nocturnal activity as in previous laboratory and field studies, rather their activity patterns were similar to those of diurnal migrants, possibly reflecting the temporally variable nature of their migration. Although the Tasmanian birds displayed higher overall activity levels than the mainland birds during the first year in captivity, the activity patterns were similar between the subspecies. Captivity appeared to influence the activity of both subspecies in the second year of the study; following the onset of molt, neither subspecies regained the activity levels of the previous year, nor did activity follow the same pattern. Possible reasons (e.g., prevention of breeding) for this are discussed. This is the most detailed study to date on the daily and seasonal activity patterns of an Australian bird in captivity. © 2010 Japan Ethological Society and Springer.

13 páginas, 6 figuras, 6 tablas.-- et al., [Background]: Oceanic islands provide unique scenarios for studying the roles of geography and ecology in driving population divergence and speciation. Assessing the relative importance of selective and neutral factors in driving population divergence is central to understanding how such divergence may lead to speciation in small oceanic islands, where opportunities for gene flow and population mixing are potentially high. Here we report a case of genetic and morphological structure in the Mascarene grey white-eye (Zosterops borbonicus) a species that shows a striking, geographically structured plumage polymorphism on the topographically and ecologically complex island of Réunion, yet is monotypic on the relatively uniform neighbouring island of Mauritius. [Results]: Analysis of 276 AFLP loci in 197 individuals revealed prolonged independent evolution of Réunion and Mauritius populations, which is congruent with previous mtDNA assessments. Furthermore, populations on Réunion showed significant differentiation into three main genetic groups separating lowland from highland areas despite the small geographic distances involved. Genetic differentiation along the altitudinal gradient is consistent with morphometric analysis of fitness-related traits. Birds in the highlands were larger, yet had relatively smaller beaks than in the lowlands, suggesting the role of selection in shaping morphology and restricting gene flow along the gradient. No genetic differentiation between plumage morphs was detected in neutral markers, suggesting that plumage differences are of recent origin. [Conclusions]: Our results suggest a dual role of vicariance and natural selection in differentiating populations of a passerine bird in an oceanic island at very small spatial scales. We propose a combination of past microallopatry driven by volcanic activity and selection-constrained dispersal along steep ecological gradients to explain the striking levels of population structure found within the island, although the possibility that genetic differences evolved in situ along the gradient cannot be ruled out at present. The lack of congruence between genetic groups and plumage morphs suggests that the latter are of recent origin and likely due to social or sexual selection acting on few loci. The presence of sharp and stable contact zones between plumage morphs suggests that they could be on independent evolutionary trajectories, yet whether or not they represent incipient species will require further research to directly assess the degree of reproductive isolation among them., Funding was provided by the Institut Français de la Biodiversité (IFB) and the French National Research Agency's (ANR) Biodiversity Program (ANR-05, NT05- 3_42075).

Predation of cocooned larvae of codling moth Cydia pomonella by silvereyes Zosterops lateralis was studied in an apple orchard in Nelson, New Zealand. Apple logs with known larval densities were made available to the birds for known periods of time, either in cages or exposed in the apple orchard. The numbers of silvereyes and the natural predation of codling moth were recorded in the same orchard. Predation was density dependent. On caged logs with an initial high density of 32 larvae, 1.1 larvae were consumed per bird‐hour; in contrast, one larva was consumed per 34.5 bird‐hours at three larvae per log. A curvilinear relationship was demonstrated between larval density and the bird‐hours required for predation; this relationship was consistent with the known density dependence of silvereye predation of codling moth. A regression of the total annual winter bird predation of larvae in the orchard on bird numbers was significant. However, the density dependence of predation resulted in declining rates of p...

Pronounced phenotypic shifts in island populations are typically attributed to natural selection, but reconstructing heterogeneity in long-term selective regimes remains a challenge. We examined a scenario of divergence proposed for species colonizing a new environment, involving directional selection with a rapid shift to a new optimum and subsequent stabilization. We provide some of the first empirical evidence for this model of evolution using morphological data from three timescales in an island bird, Zosterops lateralis chlorocephalus. In less than four millennia since separation from its mainland counterpart, a substantial increase in body size has occurred and was probably achieved in fewer than 500 generations after colonization. Over four recent decades, morphological traits have fluctuated in size but showed no significant directional trends, suggesting maintenance of a relatively stable phenotype. Finally, estimates of contemporary selection gradients indicated generally weak directional selection. These results provide a rare description of heterogeneity in long-term natural regimes, and caution that observations of current selection may be of limited value in inferring mechanisms of past adaptation due to a lack of constancy even over short time-frames. © 2008 The Author(s)., Funding was provided by grants from Natural Environment Research Council (UK) and the Australian Research Council

International audience; Although angraecoid orchids are famous for their spectacular flowers, pollinated by hawkmoths in Madagascar, two species of Angraecum endemic to the Mascarenes (sect. Hadrangis ) have atypical unscented and short-spurred flowers that are pollinated by birds. We focused on the pollination and reproductive success of Angraecum bracteosum Balf.f. & S.Moore, a member of sect. Hadrangis . We investigated the breeding system by performing a set of hand-pollination ex- periments and by observing natural pollinators using video-captures. Pollinator efficiency (pollen removal and deposition) and reproductive success (fruit set) were quantified once a week in two natural island populations during three consecutive flowering seasons (2003–2005). The orchid is self-compatible but requires pollinator services to achieve reproduction. The two white-eye song-bird species (Zosteropidae) that occur on Reunion, Zosterops borbonicus Boddaert and Zosterops oliva- Ceus L., were recorded as pollinators. However, while pollination events were rare and occasional following flower visits by Z. borbonicus , foraging of Z. oliveaceus resulted in a high frequency of successful pollinations. White-eyes typically perched on inflorescences, and probed most of the ‘‘fresh-looking’’ flowers for nectar. This study documents a probable case of bird-pollination specialization within Angraecum section Hadrangis , and sheds light on the role played by pollina- tors during the radiation of section Hadrangis in the Mascarene Archipelago.

Kulal White-eye Zosterops kulalensis is endemic to Mt Kulal, northern Kenya. It is currently considered a Vulnerable species because of its restricted range. We investigated its habitat and microhabitat use, and flocking and foraging behaviour, with respect to seasonal and diurnal variation. In the dry season, Kulal White-eye was encountered only in montane forest, where it was more abundant in glades than in closed-canopy habitats. Here it fed frequently on fruit, as most fruiting occurred in the drier months. In the wet season population density was also higher in glades than in closed-canopy forest, but birds were mostly insectivorous. Foraging in bush outside the forest was favoured. In the wet season, Kulal White-eye inhabited both the forest and the drier bush at lower altitudes, and avoided habitats with mature trees, preferring young tree formations where vegetation was thicker. Flock size was larger in the dry season, and, in the wet season, larger flocks were encountered in the morning and in late afternoon. Our study suggests that Kulal White-eye is less restricted to mature forest than previously thought. The conservation of the species requires that both the forest and the adjoining bush habitats receive adequate protection. Although some traditional human activities could be compatible with conservation, grazing of domestic animals inside the forest and the removal of large tracts of bush to create new pastures could be detrimental to the species.

The founding of new populations by small numbers of colonists has been considered a potentially important mechanism promoting evolutionary change in island populations. Colonizing species, such as members of the avian species complex Zosterops lateralis, have been used to support this idea. A large amount of background information on recent colonization history is available for one Zosterops subspecies, Z. lateralis lateralis, providing the opportunity to reconstruct the population dynamics of its colonization sequence. We used a Bayesian approach to combine historical and demographic information available on Z. l. lateralis with genotypic data from six microsatellite loci, and a rejection algorithm to make simultaneous inferences on the demographic parameters describing the recent colonization history of this subspecies in four southwest Pacific islands. Demographic models assuming mutation-drift equilibrium or a large number of founders were better supported than models assuming founder events for three of four recently colonized island populations. Posterior distributions of demographic parameters supported (i) a large stable effective population size of several thousands individuals with point estimates around 4000-5000; (ii) a founder event of very low intensity with a large effective number of founders around 150-200 individuals for each island in three of four islands, suggesting the colonization of those islands by one flock of large size or several flocks of average size; and (iii) a founder event of higher intensity on Norfolk Island with an effective number of founders around 20 individuals, suggesting colonization by a single flock of moderate size. Our inferences on demographic parameters, especially those on the number of founders, were relatively insensitive to the precise choice of prior distributions for microsatellite mutation processes and demographic parameters, suggesting that our analysis provides a robust description of the recent colonization history of the subspecies.

The orientation behaviour of Australian silvereyes, Zosterops l. lateralis, was tested during their spring migration, when they head southward to their Tasmanian breeding grounds. With only the local geomagnetic field as a cue, the birds significantly preferred their normal southerly migratory direction. Treatment with a short, strong magnetic pulse designed to alter the magnetization of single-domain magnetite led to a significant deflection towards the east for the next 4 days. This was followed by a period of non-oriented behaviour. From day 10 onwards, the birds returned to their original southerly headings. Together with previous findings, these data suggest that the navigational ‘map’ of these birds includes magnetic parameters and that a magnetite-based receptor provides them with information about their position. The transient nature of the effect is not easily explained on the basis of single-domain magnetite.

Two new species, Syringophilopisis pari sp. nov. from Poecile palustris Linnaeus (Paridae) and Torotrogla volgini sp. nov. from Emberiza elegans Temminck (Emberizidae) are described. Additionally, new host species are reported for three syringophilid species: Emberiza tristrami Swinhoe and E. rutila Pallas for Betasyringophiloidus schoeniclus (Skoracki); Sitta europaea Linnaeus (Sittidae) for Syringophilopsis sittae Skoracki et al., and Zosterops erythropleurus Swinhoe (Zosteropidae) for Neoaulonastus zosterops Skoracki et al. All avian hosts were captured in the Primorsky Krai, Russia. The syringophilid fauna presently recorded from Russia is summarized.

Using null model simulations, we tested for non-random patterns of local co-occurrence in 28 congeneric guilds of the Australian avifauna. At the scale of 1° latitude-longitude blocks. species in most guilds co-occurred more often than expected by chance. However, coexistence was significantly less than expected for six of the 28 guilds. In four of these guilds (Climacteris, Cinclosoma, Manorinia, and Psophodes. ), the species were segregated by habitat use and/or geographic range. The remaining two cases were complicated by uncertainty in taxonomy (Malurus) and unreliable field records (Corvus.). We also examined distribution patterns in five Australian guilds that are analogs of avian guilds designated by Diamond for the Bismarck Archipelago. For two of the five guilds (Pachycephala and Zosterops), co-occurrence in Australia was less than expected, mirroring an insular pattern of checkerboard distributions in the Bismarck Archipelago. For the remaining three guilds (Ptilonopus, Myzomela and Lonchura), co-occurrence was significantly greater than expected. Overall. our results suggest that competitive-based assembly rules are not important in determining species coexistence within most congeneric guilds of the Australian avifauna, at least at the large spatial scale of our analysis.

Since 1958, Apalopteron familiare has been placed in the Meliphagidae and called the Bonin Islands Honeyeater or Ogasawara Honeyeater. Previously it had been treated as a bulbul, a babbler, a sylviid warbler and a white-eye. Here we present 12S rRNA sequence evidence that shows that Apalopteron is a member of the white-eye family Zosteropidae, closely-related to the Golden White-eye (Cleptornis marchei) of the southern Mariana Islands, which was also misidentified as a honeyeater until its true affinities were revealed by field observations and DNA-DNA hybridization. The ecology and behavior of Apalopteron and Zosterops are compared and reviewed. The English name Bonin Islands White-eye is proposed for Apalopteron familiare.

1) The Japanese White-eye Zosterops japonica was studied on Miyake Island (Izu Islands) in winter to record agonistic behaviour and associated behaviour.2) The winter population consisted of the island race Z. j. stejnegeri and the mainland race Z. j. japonica (about 9%), distinguishable in size and weight. Both races exhibited agonistic behaviour at sources of concentrated food supply, and in territorial contexts, with motor patterns similar to those known for other species of Zosterops. Wing fluttering, supplanting with bill clattering and head turning, which are components of aggressive behaviour unique to the genus Zosterops, have now been observed in Z. japonica.3) Foraging flock size, feeding habits and prey hunting behaviour were also typical of Zosterops, with generalized food niche and a large repertoire of foraging behaviour.4) The frequency of wing flicking was related to restlessness and not to dominance behaviour.5) Dominance classes of birds, based on the proportion of wins in total aggressive encounters in which birds were observed, reflected their ranks in a hierarchy derived from individual relatoins. Dominace classes were not related to any of the size attributes measured. Some small mainland birds were dominant over large island birds.