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Climate change forces many species to move their ranges to higher latitudes or elevations. Resulting immigration or emigration of species might lead to functional changes, e.g., in the trait distribution and composition of ecological assemblages. Here, we combined approaches from biogeography (species distribution models; SDMs) and community ecology (functional diversity) to investigate potential effects of climate-driven range changes on frugivorous bird assemblages along a 3000 m elevational gradient in the tropical Andes. We used SDMs to model current and projected future occurrence probabilities of frugivorous bird species from the lowlands to the tree line. SDM-derived probabilities of occurrence were combined with traits relevant for seed dispersal of fleshy-fruited plants to calculate functional dispersion (FDis; a measure of functional diversity) for current and future bird assemblages. Comparisons of FDis between current and projected future assemblages showed consistent results across four dispersal scenarios, five climate models and two representative concentration pathways. Projections indicated a decrease of FDis in the lowlands, an increase of FDis at lower mid-elevations and little changes at high elevations. This suggests that functional dispersion responds differently to global warming at different elevational levels, likely modifying avian seed dispersal functions and plant regeneration in forest ecosystems along tropical mountains.
Obwohl Berichte von albinotischen oder teilalbinotischen Vögeln nicht selten sind, gibt es vom Feldsperling Passer montanus nur wenige publizierte Fälle von völligem Albinismus. Diese Arbeit beschreibt einen solchen Vogel, der im September 2001 bei Dresden gefunden wurde. Der Sperling trägt ein vollständig weißes Jugendkleid, sein Schnabel und die Beine sind gelblichweiß gefärbt. Das Präparat dieses Vogels befindet sich jetzt in der ornithologischen Sammlung des Museums für Tierkunde Dresden.
Background: Natural history museums receive a rapidly growing number of requests for tissue samples from preserved specimens for DNA-based studies. Traditionally, dried vertebrate specimens were treated with arsenic because of its toxicity and insect-repellent effect. Arsenic has negative effects on in vivo DNA repair enzymes and consequently may inhibit PCR performance. In bird collections, foot pad samples are often requested since the feet were not regularly treated with arsenic and because they are assumed to provide substantial amounts of DNA. However, the actual influence of arsenic on DNA analyses has never been tested. Findings: PCR success of both foot pad and body skin samples was significantly lower in arsenic-treated samples. In general, foot pads performed better than body skin samples. Moreover, PCR success depends on collection date in which younger samples yielded better results. While the addition of arsenic solution to the PCR mixture had a clear negative effect on PCR performance after the threshold of 5.4 μg/μl, such high doses of arsenic are highly unlikely to occur in dried zoological specimens. Conclusions: While lower PCR success in older samples might be due to age effects and/or DNA damage through arsenic treatment, our results show no inhibiting effect on DNA polymerase. We assume that DNA degradation proceeds more rapidly in thin tissue layers with low cell numbers that are susceptible to external abiotic influences. In contrast, in thicker parts of a specimen, such as foot pads, the outermost horny skin may act as an additional barrier. Since foot pads often performed better than body skin samples, the intention to preserve morphologically important structures of a specimen still conflicts with the aim to obtain optimal PCR success. Thus, body skin samples from recently collected specimens should be considered as alternative sources of DNA.
Oromia is the largest National Regional State of Ethiopia. Here we present the first comprehensive checklist of its birds. A total of 804 bird species has been recorded, 601 of them confirmed (443) or assumed (158) to be breeding birds. At least 561 are all-year residents (and 31 more potentially so), at least 73 are Afrotropical migrants and visitors (and 44 more potentially so), and 184 are Palaearctic migrants and visitors (and eight more potentially so). Three species are endemic to Oromia, 18 to Ethiopia and 43 to the Horn of Africa. 170 Oromia bird species are biome restricted: 57 to the Afrotropical Highlands biome, 95 to the Somali-Masai biome, and 18 to the Sudan-Guinea Savanna biome. 26 species of birds of Oromia are Threatened (three Critically Endangered, nine Endangered, and 14 Vulnerable), and an additional 20 species are classified as Near Threatened. International regulations affect 225 Ethiopian bird species. Of the polytypic species, a total of 620 subspecies can be taxonomically assigned to Oromia. 11 of them are endemic to Oromia, 71 to Ethiopia and 150 to the Horn of Africa. This very high diversity underlines the high responsibility of the Oromia National Regional State for bird conservation.
Global climate change is one of the major driving forces for adaptive shifts in migration and breeding phenology and possibly impacts demographic changes if a species fails to adapt sufficiently. In Western Europe, pied flycatchers (Ficedula hypoleuca) have insufficiently adapted their breeding phenology to the ongoing advance of food peaks within their breeding area and consequently suffered local population declines. We address the question whether this population decline led to a loss of genetic variation, using two neutral marker sets (mitochondrial control region and microsatellites), and one potentially selectively non-neutral marker (avian Clock gene). We report temporal changes in genetic diversity in extant populations and biological archives over more than a century, using samples from sites differing in the extent of climate change. Comparing genetic differentiation over this period revealed that only the recent Dutch population, which underwent population declines, showed slightly lower genetic variation than the historic Dutch population. As that loss of variation was only moderate and not observed in all markers, current gene flow across Western and Central European populations might have compensated local loss of variation over the last decades. A comparison of genetic differentiation in neutral loci versus the Clock gene locus provided evidence for stabilizing selection. Furthermore, in all genetic markers, we found a greater genetic differentiation in space than in time. This pattern suggests that local adaptation or historic processes might have a stronger effect on the population structure and genetic variation in the pied flycatcher than recent global climate changes.