Occupancy modeling is an essential tool for understanding species‐habitat associations, thereby helping to plan the conservation of rare and threatened wildlife species. The conservation status and ...ecology of several avian species, particularly ground‐dwelling birds, are poorly known in Ethiopia. We used camera trap‐based occupancy modeling to investigate habitat covariate influence on occupancy (Ψ) and detection probability (ρ) estimates of Moorland Francolins Scleroptila psilolaema from spatially replicated surveys across both relatively pristine and disturbed landscapes in the Afroalpine biome of Ethiopia. Model‐averaged estimate of ψ̂$$ \hat{\uppsi} $$ across all sites was 0.76 (SD = 0.28) and ρ̂$$ \hat{\uprho} $$ was 0.77 (SD = 0.13) in the pristine landscape. The ψ̂$$ \hat{\uppsi} $$ of the species in the disturbed landscape was 0.56 (SD = 0.19) and ρ̂$$ \hat{\uprho} $$ was 0.48 (SD = 0.06). As hypothesized, based on our model‐averaged beta coefficient estimates (βmean ± SE), predators significantly negatively influenced the occupancy of Moorland Francolins in pristine habitat. We also found a significant positive association of occupancy with herb species richness. Contrary to our prediction, distance to road significantly negatively influence the occupancy of the species, suggesting that occupancy probability was highest in proximity to roadsides and trails in the pristine habitat. There was no significant influence of habitat covariates on the occupancy of the species in the disturbed habitat. The most important covariates that significantly influence the detectability of the species in pristine habitat included sampling occasion and precipitation. The greater occupancy and detectability of this endemic species in the pristine habitat could be linked with the particular conservation status and management of this biodiversity hotspot in the central highlands of Ethiopia. Our results suggest that strict legal enforcement is required to sustainably preserve Moorland Francolins and the ecological integrity of the entire Afroalpine biome. We recommend using camera traps in order to develop realistic and effective conservation and management strategies for rare, sensitive, cryptic, and ground‐dwelling animals in the region.
In this research, camera trap‐based occupancy modeling was applied to investigate habitat covariates' influence on occupancy and detection probability estimates of Moorland Francolins from spatially replicated surveys in relatively pristine and disturbed landscapes in the Afroalpine biome of Ethiopia. The study species was influenced by predators, herb species richness, and distance to roads and trails in the pristine habitat. Camera traps help to plan effective conservation and management strategies for secretive ground‐dwelling animals in the topographically complex region.
Seasonal migration is prevalent in approximately one fifth of all bird species. Due to the high energetic costs of migration, consistent morphological patterns can be observed across migratory ...species. These include longer, more pointed wings and shorter tails in comparison to resident species. While evidence for distinct morphological adaptations of migratory species is well‐established, little is known about evolutionary trajectories of these morphological adaptations within groups of related species, and whether the evolution of these traits is consistent across different bird families. Here we apply a macroevolutionary approach to address this knowledge gap by comparing morphological traits and their evolution in migratory and resident species across eight families of passerine birds. We find a significant relationship of wing shape and tail length with migratory distance. When testing the evolution of wing shape and tail length in migratory and resident species, we find that a model with two distinct optima for migratory and resident species better explains the evolution of each morphological trait than a model with one evolutionary optimum. Thus, our results suggest consistent adaptive peaks in the evolution of these traits, and consistent selective pressures which improve the efficiency of long‐distance flight in migratory species and the efficiency of foraging flight in resident species. Our data provide a novel insight into the general patterns of morphological trait evolution in birds, thereby expanding the existing knowledge to a macroevolutionary scale in a field that has previously been dominated by species‐ or genera‐ specific studies.
In the Himalayas, a number of secondary contact zones have been described for vicariant vertebrate taxa. However, analyses of genetic divergence and admixture are missing for most of these examples. ...In this study, we provide a population genetic analysis for the coal tit (Periparus ater) hybrid zone in Nepal. Intermediate phenotypes between the distinctive western “spot‐winged tit” (P. a. melanolophus) and Eastern Himalayan coal tits (P. a. aemodius) occur across a narrow range of <100 km in western Nepal. As a peculiarity, another distinctive cinnamon‐bellied form is known from a single population so far. Genetic admixture of western and eastern mitochondrial lineages was restricted to the narrow zone of phenotypically intermediate populations. The cline width was estimated 46 km only with a center close to the population of the cinnamon‐bellied phenotype. In contrast, allelic introgression of microsatellite loci was asymmetrical from eastern P. a. aemodius into far western populations of phenotypic P. a. melanolophus but not vice versa. Accordingly, the microsatellite cline was about 3.7 times wider than the mitochondrial one.
In our study, we analysed patterns of divergence and admixture in the Himalayan hybrid zone of coal tits across a transect of about 1400 km from Afghanistan to East Nepal. Due to the scarcity of study material from that region only a few phylogeographic or population genetic studies exist from this area. In these cases, museum collections are a valuable source of genetic material, such as the large collections from Afghanistan and Nepal from the 1960ies to 1970ies at ZFMK Bonn used in this study.
The closely related Black-headed Bunting (Emberiza melanocephala, a western Palearctic lineage) and Red-headed Bunting (Emberiza bruniceps, an eastern Palearctic lineage) hybridize and replace each ...other south of the Caspian Sea. The parental species have distinct phenotypes and therefore morphology is useful for assessing hybridization in the contact zone. In the years of 1940 and 1977, quite a few hybrids were collected and studied morphologically. Since then, the hybrid zone appears to have expanded westwards, but there has been a time gap in the collection of morphological data. Here we reanalyze bunting specimens morphologically and compare the historical data with recent data. Morphometric and phenotypic traits from three time periods (1940, 1977 and recent) were studied to assess phenotypic variation of hybrids, pattern of hybridization, and transgressive traits in the hybrid zone. Our results show that most of the birds in the hybrid zone exhibit intermediate phenotypes (both colors and morphometric characters), ranging from the pure phenotype of either of the parental species. However, hybridization has also produced novel phenotypes not seen in any of the parents. Using a canonical discriminant function analysis, the morphometric characters separated each parental species and the hybrids quite well. Our results showed morphometric intermediacy of hybrids in accordance with phenotypes. We observe a time trend in which recent hybrids are more similar to Red-headed Buntings phenotypically compared to historical samples. This pattern is likely a signature of a westward expansion of the Red-headed Bunting into the breeding range of the Black-headed Bunting.
We studied the quill mite fauna of the family Syringophilidae, associated with bee-eaters. We examined 273 bird specimens belonging to nine closely related species of the genus
, representing two ...phylogenetic sister clades of a monophyletic group. Our examination reveals the presence of two species of the genus
, as follows: (1) a new species
sp. n. from
in the Philippines,
in Nepal and Sri Lanka, and
in Sri Lanka; and (2)
from
in Tanzania and Egypt,
in Sudan, Tanzania, Liberia, Senegal, Kenya, and D.R. Congo,
in Papua New Guinea,
in Thailand, Indonesia and Sri Lanka, and
in the Philippines. The prevalence of host infestations by syringophilid mites varied from 3.1 to 38.2%. The distribution of syringophilid mites corresponds with the sister clade phylogenetic relationships of the hosts, except for
associated with
. Possible hypotheses for the host lineage shift are proposed.
Bird-mediated seed dispersal is crucial for the regeneration and viability of ecosystems, often resulting in complex mutualistic species networks. Yet, how this mutualism drives the evolution of seed ...dispersing birds is still poorly understood. In the present study we combine whole genome re-sequencing analyses and morphometric data to assess the evolutionary processes that shaped the diversification of the Eurasian nutcracker (Nucifraga), a seed disperser known for its mutualism with pines (Pinus). Our results show that the divergence and phylogeographic patterns of nutcrackers resemble those of other non-mutualistic passerine birds and suggest that their early diversification was shaped by similar biogeographic and climatic processes. The limited variation in foraging traits indicates that local adaptation to pines likely played a minor role. Our study shows that close mutualistic relationships between bird and plant species might not necessarily act as a primary driver of evolution and diversification in resource-specialized birds.
One of the last remaining enigmas among Palearctic bird species is Vaurie’s Nightjar
Caprimulgus centralasicus
. It is known from a single specimen, said to be an adult female, collected in September ...1929 southeast of Yarkand, Xinjiang, in westernmost China, and originally identified as an Egyptian Nightjar
C. aegyptius
. All major world checklists and authors of monographs on the Caprimulgiformes accept
C. centralasicus
as a species, but efforts to rediscover it in the field have failed, meaning that occasional doubts have been expressed as to its taxonomic validity. We subjected the holotype of
C. centralasicus
to a molecular examination and renewed morphological comparisons, with the aim of resolving its status. We independently confirmed in two different laboratories that
C. centralasicus
has an identical partial fragment of the mitochondrial gene cytochrome oxidase subunit 1 b (COI) as five European Nightjars
C. europaeus
. The overall plumage coloration (but not size) of
C. centralasicus
is reasonably similar, especially on the upperparts, to at least some specimens of
C. europaeus
of the subspecies
C. e. unwini
and
C. e. plumipes
, and by implication to that of
C. e. dementievi
too, while several specimens of Sykes’s Nightjar
C. mahrattensis
are a reasonably close match in coloration to
C. centralasicus
, also lack an obvious nuchal collar, and possess a similar-length tail and pattern. There is a high degree of likelihood that
C. centralasicus
is a synonym of
C. e. plumipes
, but the small size of the holotype compared to
C. europaeus
persists in being difficult to fully rationalize, although we believe that the bird is, in fact, a fledgling in its first plumage, parts of which are still growing, which would explain much of the difference. In addition, based on current data, there is no correspondence between described subspecies of
C. europaeus
and genetic variability. Phylogeographic structure within
C. europaeus
and its correspondence with morphological, especially plumage variation, requires further investigation using a more comprehensive geographic sampling from the breeding grounds.
Aim
Although patterns of biodiversity across the globe are well studied, there is still a controversial debate about the underlying mechanisms and their generality across biogeographic scales. In ...particular, it is unclear to what extent diversity patterns along environmental gradients are directly driven by abiotic factors, such as climate, or indirectly mediated through biotic factors, such as resource effects on consumers.
Location
Andes, Southern Ecuador; Mt. Kilimanjaro, Tanzania.
Methods
We studied the diversity of fleshy‐fruited plants and avian frugivores at the taxonomic level, that is, species richness and abundance, as well as at the level of functional traits, that is, functional richness and functional dispersion. We compared two important biodiversity hotspots in mountain systems of the Neotropics and Afrotropics. We used field data of plant and bird communities, including trait measurements of 367 plant and bird species. Using structural equation modeling, we disentangled direct and indirect effects of climate and the diversity of plant communities on the diversity of bird communities.
Results
We found significant bottom‐up effects of fruit diversity on frugivore diversity at the taxonomic level. In contrast, climate was more important for patterns of functional diversity, with plant communities being mostly related to precipitation, and bird communities being most strongly related to temperature.
Main conclusions
Our results illustrate the general importance of bottom‐up mechanisms for the taxonomic diversity of consumers, suggesting the importance of active resource tracking. Our results also suggest that it might be difficult to identify signals of ecological fitting between functional plant and animal traits across biogeographic regions, since different species groups may respond to different climatic drivers. This decoupling between resource and consumer communities could increase under future climate change if plant and animal communities are consistently related to distinct climatic drivers.
Although patterns of biodiversity across the globe are well studied, there is still a controversial debate about the underlying mechanisms and their generality across biogeographic scales. We found significant bottom‐up effects of fruit diversity on frugivore diversity at the taxonomic level. In contrast, climate was more important for patterns of functional diversity, with plant communities being mostly related to precipitation, and bird communities being most strongly related to temperature.
Tropical mountains are hotspots of biodiversity, but the factors that generate this high diversity remain poorly understood. To identify possible mechanisms that influence avian species assemblages ...in the tropical Andes, we studied the functional and phylogenetic diversity and the structure of species assemblages of an avian feeding guild. We analysed how functional and phylogenetic diversity, structure and composition of frugivorous bird assemblages changed along a 3300 m elevational transect from the lowlands to the tree line with a novel combination of functional and phylogenetic approaches, and used null models to infer possible drivers of the observed patterns. Species richness, functional richness and phylogenetic diversity decreased almost monotonically with increasing elevation, but assemblage structure and composition changed abruptly in the Andean foothills at around 1200 m. In the lowland assemblages, species were functionally and phylogenetically less similar than expected from null models, whereas species in the highland assemblages were functionally and phylogenetically more similar than expected by chance, suggesting an abrupt reduction in the number of functionally and phylogenetically distinct species in the transition from lowlands to the highlands. Nevertheless, the functional and phylogenetic evenness of the assemblages, i.e. the regularity of the spacing of species in functional trait space and phylogeny, remained constant along the gradient, which suggests that the mechanisms that influence the co-occurrence of species within the assemblages are similar in lowlands and highlands. The observed differences between lowland and highland assemblages imply sharp distributional limits for frugivorous bird species in the Andean foothills, probably caused by environmental factors other than climate, e.g. changes in habitat types or topography, or independent species radiations in lowlands and highlands. These strong distributional limits may hinder uphill range shifts of frugivorous bird species, and the plant species they disperse, in the tropical Andes as a response to climate change.
Aim: Zoogeographie patterns in the Himalayas and their neighbouring Southeast Asian mountain ranges include elevational parapatry and ecological segregation, particularly among passerine bird ...species. We estimate timings of lineage splits among close relatives from the north Palaearctic, the Sino-Himalayan mountain forests and from adjacent Southeast Asia. We also compare phylogeographic affinities and timing of radiation among members of avian communities from different elevational belts. Location: East Asia. Methods: We reconstructed molecular phylogenies based on a mitochondrial marker (cytochrome b) and multilocus data sets for seven passerine groups: Aegithalidae, Certhiidae (Certhia), Fringillidae (Pyrrhula) y Paridae (Periparus), Phylloscopidae, Regulidae and Timaliidae (Garrulax sensu lato). Molecular dating was carried out using a Bayesian approach applying a relaxed clock in BEAST. Time estimates were inferred from three independent calibrations based on either a fixed mean substitution rate or fixed node ages. The biogeographic history of each group was reconstructed using a parsimony-based approach. Results: Passerine radiation in Southeast Asia can be divided into roughly three major phases of separation events. We infer that an initial Miocene radiation within the Southeast Asian region included invasions of (sub) tropical faunal elements from the Indo-Burmese region to the Himalayan foothills and further successive invasions to Central Asia and Taiwan towards the early Pliocene. During two further Pliocene/Pleistocene phases, the subalpine mountain belt of the Sino-Himalayas was initially invaded by boreal species with clear phylogenetic affinities to the north Palaearctic taiga belt. Most terminal splits between boreal Himalayan/Chinese sister taxa were dated to the Pleistocene. Main conclusions: Extant patterns of elevational parapatry and faunal transition in the Sino-Himalayas originated from successive invasions from different climatic regions. The initiation of Southeast Asian passerine diversification and colonization of the Himalayan foothills in the mid-Miocene coincides with the postulated onset of Asian monsoon climate and the resulting floral and faunal turnovers. Patterns of elevational parapatry were established by southward invasions of boreal avifaunal elements to the subalpine Sino-Himalayan forest belt that were strongly connected to climate cooling towards the end of the Pliocene. Current patterns of allopatry and parapatry in boreal species (groups) were shaped through Pleistocene forest fragmentation in East Asia.
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