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1.
Naturwissenschaften ; 108(5): 42, 2021 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-34491450

RESUMO

Urbanisation is proceeding at an alarming rate which forces wildlife to either retreat from urban areas or cope with novel stressors linked to human presence and activities. For example, urban stressors like anthropogenic noise, artificial light at night and chemical pollution can have severe impacts on the physiology of wildlife (and humans), in particular the immune system and antioxidant defences. These physiological systems are important to combat and reduce the severity of parasitic infections, which are common among wild animals. One question that then arises is whether urban-dwelling animals, whose immune and antioxidant system are already challenged by the urban stressors, are more susceptible to parasitic infections. To assess this, we studied nestlings of Eurasian kestrels (Falco tinnunculus) in Vienna, Austria, during 2015 and 2017. We measured biomarkers of innate immune function, oxidative stress and body mass index and ectoparasite infection intensity in 143 nestlings (from 56 nests) along an urban gradient. Nestlings in more urbanised areas had overall fewer ectoparasites, lower haemolysis (complement activity) and lower body mass index compared to nestlings in less urbanised areas. None of the other immune or oxidative stress markers were associated with the urban gradient. Despite some non-significant results, our data still suggest that kestrel nestlings experience some level of reduced physiological health, perhaps as a consequence of exposure to more urban stressors or altered prey availability in inner-city districts even though they had an overall lower ectoparasite burden in these heavily urbanised areas.


Assuntos
Falconiformes , Hemólise , Animais , Antioxidantes , Humanos , Estresse Oxidativo , Urbanização
2.
Zootaxa ; 4691(3): zootaxa.4691.3.5, 2019 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-31719393

RESUMO

We re-examined the putative type specimen of Society Kingfisher Todiramphus veneratus (J. F. Gmelin, 1788) in the Naturhistorisches Museum Wien (NMW 50.633) and conclude based on plumage that it represents the taxon from Moorea, T. veneratus youngi Sharpe, 1892, rather than nominate T. veneratus veneratus from Tahiti. X-rays reveal that it was prepared using techniques common in the late 18th century, and that its preparation style matches that of other specimens collected during Cook's three voyages. NMW 50.633 has been assumed to be the one, or one of a number of, specimen(s) used by Latham to describe and illustrate his 'Venerated Kingfisher' (present-day Society Kingfisher), which was the basis of the later valid introduction of the name Alcedo venerata by J. F. Gmelin. However, whereas the description and an unpublished illustration in Latham's archives agree closely with veneratus from Tahiti, NMW 50.633 appears to represent Moorea youngi. While this finding does not compromise the definition of Society Kingfisher veneratus, it leaves it without a safely identified type specimen. We also examined a Moorea specimen in the National Museums Liverpool (LIVCM D2366) that is almost as old as NMW 50.633, but which X-rays suggest had a different origin than NMW 50.633.


Assuntos
Aves , Animais , Polinésia
3.
Curr Biol ; 29(2): 340-349.e7, 2019 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-30639104

RESUMO

Human-induced environmental change and habitat fragmentation pose major threats to biodiversity and require active conservation efforts to mitigate their consequences. Genetic rescue through translocation and the introduction of variation into imperiled populations has been argued as a powerful means to preserve, or even increase, the genetic diversity and evolutionary potential of endangered species [1-4]. However, factors such as outbreeding depression [5, 6] and a reduction in available genetic diversity render the success of such approaches uncertain. An improved evaluation of the consequence of genetic restoration requires knowledge of temporal changes to genetic diversity before and after the advent of management programs. To provide such information, a growing number of studies have included small numbers of genomic loci extracted from historic and even ancient specimens [7, 8]. We extend this approach to its natural conclusion, by characterizing the complete genomic sequences of modern and historic population samples of the crested ibis (Nipponia nippon), an endangered bird that is perhaps the most successful example of how conservation effort has brought a species back from the brink of extinction. Though its once tiny population has today recovered to >2,000 individuals [9], this process was accompanied by almost half of ancestral loss of genetic variation and high deleterious mutation load. We furthermore show how genetic drift coupled to inbreeding following the population bottleneck has largely purged the ancient polymorphisms from the current population. In conclusion, we demonstrate the unique promise of exploiting genomic information held within museum samples for conservation and ecological research.


Assuntos
Aves/genética , Genoma , Endogamia , Polimorfismo Genético , Animais , Espécies em Perigo de Extinção
4.
PLoS One ; 13(2): e0191956, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29420544

RESUMO

As the world experiences rapid urban expansion, natural landscapes are being transformed into cities at an alarming rate. Consequently, urbanization is identified as one of the biggest environmental challenges of our time, yet we lack a clear understanding of how urbanization affects free-living organisms. Urbanization leads to habitat fragmentation and increased impervious surfaces affecting for example availability and quality of food. Urbanization is also associated with increased pollution levels that can affect organisms directly, via ecophysiological constraints and indirectly by disrupting trophic interactions in multi-species networks. Birds are highly mobile, while an individual is not necessarily exposed to urban stressors around the clock, but nestlings of altricial birds are. Such a city-dwelling species with a long nestling phase is the Eurasian kestrel (Falco tinnunculus) in Vienna, Austria, which forage on a diverse diet differing in composition from rural habitats. Furthermore, prey items vary in nutritional value and contents of micronutrients like carotenoids, which might impact the nestlings' health. Carotenoids are pigments that are incorporated into integument tissues but also have antioxidant and immunostimulatory capacity, resulting in a trade-off between these functions. In nestlings these pigments function in parent-offspring communication or sibling competition by advertising an individual's physical or physiological condition. Anthropogenic disturbance and pollutants could have disruptive effects on the coloration of these traits. In this study, we measured carotenoid based coloration and other indicators of individual health (body condition and susceptibility to the ectoparasite Carnus hemapterus) of 154 nestling kestrels (n = 91 nests) along an urban gradient from 2010 to 2015. We found skin yellowness of nestlings from nest-sites in the city-center to be least pronounced. This result might indicate that inner-city nestlings are strongly affected by urban stressors and depleted their stores of dietary carotenoids for health-related functions rather than coloration. In addition, skin yellowness intensified with age and was stronger pronounced in earlier nests. Since the immune system of nestlings is still developing, younger chicks might need more antioxidants to combat environmental stress. Additionally, parasite infection intensity was highest in nestlings with less intense skin yellowness (paler or less yellow pigmented integuments) and in earlier nests of the season. In combination with results from previous studies, our findings provide further support for the low quality of the inner-city habitat, both in terms of productivity and individual health.


Assuntos
Carotenoides/metabolismo , Cor , Falconiformes , Urbanização , Animais , Áustria
5.
Zootaxa ; 4216(4): zootaxa.4216.4.1, 2017 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-28183111

RESUMO

We present a phylogeny of all booted eagles (38 extant and one extinct species) based on analysis of published sequences from seven loci. We find molecular support for five major clades within the booted eagles: Nisaetus (10 species), Spizaetus (4 species), Clanga (3 species), Hieraaetus (6 species) and Aquila (11 species), requiring generic changes for 14 taxa. Additionally, we recommend that the Long-crested Eagle (Lophaetus occipitalis) and the Black Eagle (Ictinaetus malaiensis) remain in their monotypic genera, due to their distinctive morphology. We apply the recently resurrected genus Clanga for the spotted eagles (previously Aquila spp.) to resolve the paraphyly of the genus Aquila such that the clade including the Booted Eagle (H. pennatus), Little Eagle (H. morphnoides), Pygmy Eagle (H. weiskei), Ayres's Eagle (H. ayresii) and Wahlberg's Eagle (H. wahlbergi) can remain in the genus Hieraaetus. The Rufous-bellied Eagle should be retained in the genus Lophotriorchis. For consistency in English names, we recommend that the term "hawk-eagles" be used only for the species in the genera Nisaetus and Spizaetus. We suggest following new or modified English names: Cassin's Eagle (Aquila africana), Bonaparte's Eagle (A. spilogaster), Ayres's Eagle (Hieraaetus ayresii), and Black-and-chestnut Hawk-Eagle (Spizaetus isidori).


Assuntos
Águias/classificação , Filogenia , Distribuição Animal , Animais , Águias/genética
6.
Mol Phylogenet Evol ; 107: 499-502, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28017858

RESUMO

The phylogenetic position of the extinct Mascarene Parrot Mascarinus mascarin from La Réunion has been unresolved for centuries. A recent molecular study unexpectedly placed M. mascarin within the clade of phenotypically very different Vasa parrots Coracopsis. Based on DNA extracted from the only other preserved Mascarinus specimen, we show that the previously obtained cytb sequence is probably an artificial composite of partial sequences from two other parrot species and that M. mascarin is indeed a part of the Psittacula diversification, placed close to P. eupatria and P. wardi.


Assuntos
Papagaios/classificação , Filogenia , Animais , Sequência de Bases , Citocromos b/genética , Loci Gênicos , Mitocôndrias/genética , Polimorfismo Genético , Alinhamento de Sequência , Especificidade da Espécie
7.
PLoS One ; 11(5): e0154231, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27168078

RESUMO

Known with certainty solely from a unique male specimen collected in central Brazil in the first quarter of the 19th century, the Critically Endangered (Possibly Extinct) Hooded Seedeater Sporophila melanops has been one of the great enigmas of Neotropical ornithology, arguably the only one of a host of long-lost species from Brazil to remain obstinately undiscovered. We reanalysed the morphology of the type specimen, as well as a female specimen postulated to represent the same taxon, and sequenced mitochondrial DNA (COI and Cyt-b) from both individuals. Furthermore, we visited the type locality, at the border between Goiás and Mato Grosso, and its environs on multiple occasions at different seasons, searching for birds with similar morphology to the type, without success. Novel genetic and morphological evidence clearly demonstrates that the type of S. melanops is not closely related to Yellow-bellied Seedeater S. nigricollis, as has been frequently postulated in the literature, but is in fact a representative of one of the so-called capuchinos, a clade of attractively plumaged seedeaters that breed mostly in the Southern Cone of South America. Our morphological analysis indicates that S. melanops has a hitherto unreported dark-coffee throat and that it is probably a Dark-throated Seedeater S. ruficollis collected within its wintering range, acquiring breeding plumage and showing melanism on the cap feathers. Alternatively, it may be a melanistic-capped individual of a local population of seedeaters known to breed in the Esteros del Iberá, Corrientes, Argentina, to which the name S. ruficollis might be applicable, whilst the name S. plumbeiceps might be available for what is currently known as S. ruficollis. A hybrid origin for S. melanops cannot be ruled out from the available data, but seems unlikely. The purported female specimen of S. melanops pertains either to S. nigricollis or to Double-collared Seedeater S. caerulescens based on genetic and morphological data, and thus cannot be a female of S. melanops. We conclude that Sporophila melanops is not typical of any natural population of seedeaters, appears to have been collected far from its breeding grounds while overwintering in central Brazil, and should not be afforded any conservation status.


Assuntos
Especiação Genética , Passeriformes/genética , Filogenia , Pigmentação/genética , Animais , Argentina , Tamanho Corporal , Brasil , Citocromos b/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Feminino , Masculino , Passeriformes/classificação , Análise de Sequência de DNA
8.
Zookeys ; (580): 145-52, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110210

RESUMO

The type locality of Pterocles exustus Temminck, 1825, is 'West coast of Africa, Egypt and Nubia'. This is problematic because it includes the type locality of Pterocles exustus floweri (Nicoll, 1921), which is Fayum, Egypt. In the interest of clarification and to preserve stability of nomenclature, a non-Egyptian specimen from the type series of Pterocles exustus is designated as lectotype of the taxon, and the type locality is restricted to Senegal.

9.
Front Zool ; 11: 48, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24872836

RESUMO

INTRODUCTION: Urbanization is a global phenomenon that is encroaching on natural habitats and decreasing biodiversity, although it is creating new habitats for some species. The Eurasian kestrel (Falco tinnunculus) is frequently associated with urbanized landscapes but it is unclear what lies behind the high densities of kestrels in the urban environment. RESULTS: Occupied nest sites in the city of Vienna, Austria were investigated along a gradient of urbanization (percentage of land covered by buildings or used by traffic). Field surveys determined the abundance of potential prey (birds and rodents) and the results were compared to the birds' diets. A number of breeding parameters were recorded over the course of three years. The majority of kestrels breed in semi-natural cavities in historic buildings. Nearest neighbour distances (NND) were smallest and reproductive success lowest in the city centre. Abundance of potential prey was not found to relate to the degree of urbanization but there was a significant shift in the birds' diets from a heavy reliance on rodents in the outskirts of the city to feeding more on small birds in the centre. The use of urban habitats was associated with higher nest failure, partly associated with predation and nest desertion, and with significantly lower hatching rates and smaller fledged broods. CONCLUSIONS: High breeding densities in urban habitats do not necessarily correlate with high habitat quality. The high density of kestrel nests in the city centre is probably due to the ready availability of breeding cavities. Highly urbanized areas in Vienna are associated with unexpected costs for the city dwelling-raptor, in terms both of prey availability and of reproductive success. The kestrel appears to be exploiting the urban environment but given the poor reproductive performance of urban kestrels it is likely that the species is falling into an ecological trap.

10.
BMC Res Notes ; 4: 197, 2011 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-21676254

RESUMO

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.

11.
Mol Phylogenet Evol ; 53(3): 703-15, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19635577

RESUMO

Buteonine hawks represent one of the most diverse groups in the Accipitridae, with 58 species distributed in a variety of habitats on almost all continents. Variations in migratory behavior, remarkable dispersal capability, and unusual diversity in Central and South America make buteonine hawks an excellent model for studies in avian evolution. To evaluate the history of their global radiation, we used an integrative approach that coupled estimation of the phylogeny using a large sequence database (based on 6411 bp of mitochondrial markers and one nuclear intron from 54 species), divergence time estimates, and ancestral state reconstructions. Our findings suggest that Neotropical buteonines resulted from a long evolutionary process that began in the Miocene and extended to the Pleistocene. Colonization of the Nearctic, and eventually the Old World, occurred from South America, promoted by the evolution of seasonal movements and development of land bridges. Migratory behavior evolved several times and may have contributed not only to colonization of the Holarctic, but also derivation of insular species. In the Neotropics, diversification of the buteonines included four disjunction events across the Andes. Adaptation of monophyletic taxa to wet environments occurred more than once, and some relationships indicate an evolutionary connection among mangroves, coastal and várzea environments. On the other hand, groups occupying the same biome, forest, or open vegetation habitats are not monophyletic. Refuges or sea-level changes or a combination of both was responsible for recent speciation in Amazonian taxa. In view of the lack of concordance between phylogeny and classification, we propose numerous taxonomic changes.


Assuntos
Migração Animal , Evolução Molecular , Falcões/genética , Filogenia , Animais , Teorema de Bayes , Núcleo Celular/genética , América Central , DNA Mitocondrial/genética , Ecossistema , Falcões/classificação , Funções Verossimilhança , Modelos Genéticos , Conformação de Ácido Nucleico , Alinhamento de Sequência , Análise de Sequência de DNA , América do Sul
12.
Mol Ecol ; 16(7): 1497-517, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17391272

RESUMO

Microsatellite as well as sequence analysis of the mitochondrial control region were applied to infer phylogeography and population genetic structure of the saker falcon (Falco cherrug). Furthermore, we compared the patterns of mitochondrial haplotypes with the variation of microsatellite alleles among the species of the hierofalcon complex (F. cherrug, Falco rusticolus, Falco biarmicus, Falco jugger) to test hypotheses on population history. Historical samples from museum specimens of F. cherrug were analysed together with samples from contemporary populations to investigate possible influences of hybrid falcons escaped from falconry on the genetic composition. In the mitochondrial DNA analysis, none of the four species represents a monophyletic group. Moreover, there are no clearly defined groups of haplotypes corresponding to taxonomic entities. In the microsatellite analysis most of the variation is shared between species and no clear differentiation by private alleles is found. Yet, with a Bayesian clustering method based on allele frequencies, a differentiation of F. cherrug, F. rusticolus and two geographic groups of F. biarmicus was detected. Results from both nuclear and mitochondrial markers are compatible with the previously postulated 'Out of Africa' hypothesis assuming an African origin of the hierofalcons. From an ancestral African population, F. cherrug, F. rusticolus and F. jugger split off in separate waves of immigration into Eurasia and South Asia. A combination of evolutionary processes, including incomplete lineage sorting as well as hybridization, may be responsible for the currently observed genetic patterns in hierofalcons.


Assuntos
Falconiformes/genética , Genética Populacional , Hibridização Genética , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Análise por Conglomerados , DNA Mitocondrial/genética , Frequência do Gene , Geografia , Haplótipos/genética , Repetições de Microssatélites/genética , Dados de Sequência Molecular , Dinâmica Populacional , Análise de Componente Principal , Análise de Sequência de DNA , Especificidade da Espécie
13.
Mol Phylogenet Evol ; 27(2): 328-42, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12695095

RESUMO

DNA sequences of the mitochondrial nd6 gene and the non-repetitive part of the pseudo-control region (PsiCR) were isolated from 101 individuals to analyze the phylogenetic relationships among all buzzards of the genus Buteo and other buteonine genera. Comparisons of the two marker sequences indicate that the PsiCR evolved two times faster than the nd6 gene. The PsiCR proved to be an efficient, neutral genetic marker sequence for phylogenetic analyses at the intrageneric level, especially suitable for analyses based on old tissues, where only short fragments can be obtained. The molecular data set implies a neotropical origin of the genus Buteo. Monophyly of the genus Buteo as currently defined is contradicted due to the positions of Asturina nitida, Geranoaetus melanoleucus, Buteo magnirostris, and Buteo leucorrhous. These findings suggest several taxonomic consequences. A. nitida and G. melanoleucus should be included into the genus Buteo. Moreover, B. leucorrhous should be transferred into the genus Percnohierax (which clusters with Parabuteo), and B. magnirostris into the genus Rupornis. According to this classification of the genus Buteo, the basal lineage of the genus is formed by a clade containing Buteo polyosoma, Buteo poecilochrous, and Buteo melanoleucus. The "woodland buteos" form a paraphyletic assemblage with B. magnirostris as a clearly separated lineage basal to the genus Buteo.


Assuntos
Aves/classificação , DNA Mitocondrial/genética , Filogenia , Animais , Sequência de Bases , Aves/genética , Análise por Conglomerados , Primers do DNA/genética , Variação Genética , Geografia , Funções Verossimilhança , Dados de Sequência Molecular
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