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1.
Mol Phylogenet Evol ; 198: 108135, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38925425

RESUMO

Historical specimens from museum collections provide a valuable source of material also from remote areas or regions of conflict that are not easily accessible to scientists today. With this study, we are providing a taxon-complete phylogeny of snowfinches using historical DNA from whole skins of an endemic species from Afghanistan, the Afghan snowfinch, Pyrgilauda theresae. To resolve the strong conflict between previous phylogenetic hypotheses, we generated novel mitogenome sequences for selected taxa and genome-wide SNP data using ddRAD sequencing for all extant snowfinch species endemic to the Qinghai-Tibet Plateau (QTP) and for an extended intraspecific sampling of the sole Central and Western Palearctic snowfinch species (Montifringilla nivalis). Our phylogenetic reconstructions unanimously refuted the previously suggested paraphyly of genus Pyrgilauda. Misplacement of one species-level taxon (Onychostruthus tazcanowskii) in previous snowfinch phylogenies was undoubtedly inferred from chimeric mitogenomes that included heterospecific sequence information. Furthermore, comparison of novel and previously generated sequence data showed that the presumed sister-group relationship between M. nivalis and the QTP endemic M. henrici was suggested based on flawed taxonomy. Our phylogenetic reconstructions based on genome-wide SNP data and on mitogenomes were largely congruent and supported reciprocal monophyly of genera Montifringilla and Pyrgilauda with monotypic Onychostruthus being sister to the latter. The Afghan endemic P. theresae likely originated from a rather ancient Pliocene out-of-Tibet dispersal probably from a common ancestor with P. ruficollis. Our extended trans-Palearctic sampling for the white-winged snowfinch, M. nivalis, confirmed strong lineage divergence between an Asian and a European clade dated to 1.5 - 2.7 million years ago (mya). Genome-wide SNP data suggested subtle divergence among European samples from the Alps and from the Cantabrian mountains.


Assuntos
Genoma Mitocondrial , Passeriformes , Filogenia , Animais , Passeriformes/genética , Passeriformes/classificação , Polimorfismo de Nucleotídeo Único , DNA Mitocondrial/genética , Análise de Sequência de DNA , Museus
2.
BMC Genomics ; 21(1): 581, 2020 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-32847513

RESUMO

BACKGROUND: The Quaternary had worldwide consequences in forming the contemporary diversity of many populations, species and communities, which is characterized by marked climatic oscillations between glacial and interglacial periods. The origin and evolution of biodiversity in mountainous areas are highly dependent on historical orogenesis and associated climatic changes. The Chinese grouse Tetrastes sewerzowi is a forest-dwelling species endemic to the mountains to the east of the Qinghai-Tibet Plateau, which has been listed as Near Threatened with a decreasing trend by the IUCN because of ongoing deforestation and fragmentation of coniferous forests. It is important to place current population status into a broader ecological and evolutionary context to understand their demographic history. RESULTS: Analyses of the Chinese Grouse genome revealed fluctuations throughout the Pleistocene in effective population size. Populations decreased during early to middle Pleistocene but showed an expansion during late Pleistocene which was then followed by a sharp decline during the last glacial maximum (LGM). Ecological niche modeling indicated that a suitable habitat shift between high altitude regions to low altitude regions was due to a changing climate. This result parallels patterns of population size change in Chinese Grouse estimated from PSMC modelling, which suggested an expansion in population size from the last interglacial period (LIG) and then a peak and a bottleneck occurring at the last glacial maximum (LGM). Furthermore, the present-day distribution of Chinese Grouse is greatly reduced and fragmented. It will likely become even more fragmented in the future since coniferous forest cover is threatened in the region of their distribution and the availability of such habitat restricts their ecological niche. CONCLUSIONS: The Chinese Grouse have experienced substantial population size changes from the beginning to the LIG and reached a peak before the LGM. A sharp decrease and bottleneck occurred during the LGM, when the coniferous forests were subjected to extensive loss. The results inferred from the whole genome sequencing and species distribution models both support historical population fluctuations. The distribution of the Chinese Grouse is strongly dependent on the coniferous forest cover. To protect the fragmented coniferous forests is an essential action to protect the Chinese Grouse.


Assuntos
Ecossistema , Galliformes , Animais , China , Variação Genética , Genômica , Filogenia , Filogeografia , Tibet
3.
Mol Phylogenet Evol ; 107: 538-550, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27965081

RESUMO

A recent full species-level phylogeny of tits, titmice and chickadees (Paridae) has placed the Chinese endemic black-bibbed tit (Poecile hypermelaenus) as the sister to the Palearctic willow tit (P. montanus). Because this sister-group relationship is in striking disagreement with the traditional affiliation of P. hypermelaenus close to the marsh tit (P. palustris) we tested this phylogenetic hypothesis in a multi-locus analysis with an extended taxon sampling including sixteen subspecies of willow tits and marsh tits. As a taxonomic reference we included type specimens in our analysis. The molecular genetic study was complemented with an analysis of biometric data obtained from museum specimens. Our phylogenetic reconstructions, including a comparison of all GenBank data available for our target species, clearly show that the genetic lineage previously identified as P. hypermelaenus actually refers to P. weigoldicus because sequences were identical to that of a syntype of this taxon. The close relationship of P. weigoldicus and P. montanus - despite large genetic distances between the two taxa - is in accordance with current taxonomy and systematics. In disagreement with the previous phylogenetic hypothesis but in accordance with most taxonomic authorities, all our P. hypermelaenus specimens fell in the sister clade of all western and eastern Palearctic P. palustris. Though shared haplotypes among the Chinese populations of the two latter species might indicate mitochondrial introgression in this part of the breeding range, further research is needed here due to the limitations of our own sampling.


Assuntos
Passeriformes/classificação , Animais , China , Código de Barras de DNA Taxonômico , DNA Mitocondrial/genética , Loci Gênicos , Passeriformes/genética , Filogenia , Filogeografia , Especificidade da Espécie
4.
Biol Lett ; 13(4)2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28446617

RESUMO

Avian incubation temperatures oscillate within narrow limits to ensure proper embryonic development. However, field observations and experimental studies have found that some species can tolerate very low incubation temperatures, either regularly or occasionally. We artificially incubated eggs from five domestic species, which represent a range of egg sizes, to examine whether a diversity of avian species could exhibit an unusual hypothermia tolerance, as observed in the field. We found that eggs of the chicken (Gallus gallus domesticus), pigeon (Columba livia domestica), Japanese quail (Coturnix japonica) and budgerigar (Melopsittacus undulatus) survived the incubation period and hatched after experiencing 10°C hypothermia for 6 h each day. However, embryos of white-rumped munia (Lonchura striata) died after 10 days of hypothermia. Our results showed that unusual hypothermia tolerance occurs in several avian species. This phenomenon might have been selected through the evolutionary history of birds. Future research should identify the importance of phylogeny, egg size and embryonic stage in tolerance to hypothermia.


Assuntos
Hipotermia , Animais , Aves , Columbidae , Coturnix , Desenvolvimento Embrionário
5.
Heliyon ; 9(9): e20082, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37809652

RESUMO

Personality traits, the consistent individual behavioral differences, are currently gaining much attention in studies of natural bird populations. However, associations between personality traits and parasite infections are not often investigated. Even less attention has been given to studies of birds in the high-elevation region such as the Tibetan plateau. This research aims to examine the relationship between avian malaria parasites and two personality traits in a population of the Chestnut Thrush (Turdus rubrocanus) breed in the Tibetan plateau. Our results revealed no evidence of sex bias in malaria parasite prevalence. Furthermore, we found no effect of infection status on two personality scores: activity and boldness. Additionally, no effects on the activity level or boldness were observed for different parasite lineages of Haemoproteus, Leucocytozoon, the sex of the birds, or their interactions. Similarly, we did not find any relationship between activity level and boldness with nestling numbers, sex, or their interactions. Notably, individuals with a larger number of offspring tended to display greater boldness. Our findings indicate that blood parasite infections are common in this population but do not significantly impact the personality of the birds.

6.
Int Orthop ; 36(3): 619-26, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21805070

RESUMO

PURPOSE: We reviewed data to determine outcomes for 21 consecutive Vancouver type B1 or type C periprosthetic fractures that we treated between 2001 and 2008 using a nickel-titanium shape-memory sawtooth-arm embracing fixator. METHODS: The study participants were 12 men and 9 women (mean age, 70.8 years; range, 42-85 years). The average duration of follow-up monitoring was 39.7 months (range, 1-78 months). In five cases, cables and screws were used for further stabilisation. No bone grafting was performed for any of the patients. RESULTS: Results were satisfactory, except for one patient who died one month after surgery from a cause unrelated to arthroplasty. Bone union was achieved in the remaining 20 cases within an average of 5.25 months. No implant failures or malunions occurred in any of the patients. The average Harris hip score at the final follow-up examination was 79.3 points. CONCLUSIONS: Our results show that the embracing fixator is a valid alternative treatment for Vancouver type B1 or type C periprosthetic femoral fractures.


Assuntos
Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas , Fixadores Internos , Níquel , Fraturas Periprotéticas/cirurgia , Titânio , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Materiais Biocompatíveis , Feminino , Fixação Interna de Fraturas/instrumentação , Fixação Interna de Fraturas/métodos , Humanos , Masculino , Pessoa de Meia-Idade , Osseointegração , Complicações Pós-Operatórias , Desenho de Prótese , Resultado do Tratamento
7.
Commun Biol ; 5(1): 4, 2022 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-35013514

RESUMO

Existing sexual selection theory postulates that a sufficiently large variation in female fecundity or other direct benefits are fundamental for generating male mate choice. In this study, we suggest that, in addition to pre-pairing preferences, choosy males can also have different post-pairing behaviors, a factor which has been comparatively overlooked by previous studies. We found that both male preferences and female traits could evolve much more easily than previously expected when the choosy males that paired with unpreferred females would allocate more efforts to seeking additional post-pairing mating opportunities. Furthermore, a costly female trait could evolve when there was a trade-off between seeking additional mating and paternal care investment within social pair for choosy males. Finally, a costly male preference and a costly female trait might still evolve and reach a stable polymorphic state in the population, which might give rise to a high variability in male choice and female traits in nature. We suggest that male mate choice may be even more common than expected, which needs to be verified empirically.


Assuntos
Evolução Biológica , Comportamento Sexual Animal , Seleção Sexual , Animais , Feminino , Masculino
8.
Curr Zool ; 68(3): 315-323, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35592343

RESUMO

In recent years, researchers have been attempting to relate differences in personality (e.g., boldness, aggressiveness, exploration tendency) to variation in cognition (performances in tasks that require learning, reasoning, attention, or memory, etc.) both theoretically and empirically. However, it is unclear on what basis personality and cognition might be associated with each other. Previous theory suggests a connection between fast-slow personality types and cognitive speed-accuracy tradeoffs. In this study, we tested this hypothesis in budgerigars and found that, in their 1st associative learning, birds with fast personality (less fearful of handling stress) were fast learners in the beginning, while slow personality individuals improved faster, but both types of birds did not differ in accuracy. However, these relationships were context-dependent. No significant relationship was found in subsequent learning tasks (reversal learning and a 2nd associative learning) in the familiar context (task setup and apparatus similar to the 1st associative learning). We then conducted a problem-solving experiment with novel setup and apparatus to test 1 possible explanation that the association between personality and cognition in the 1st associative learning might be caused by noncognitive constraint, such as fearfulness when facing novel task setup and apparatus. We found that fast individuals interacted more with the problem box and solved it, whereas the slow birds were not. We suggest that personalities can influence cognitive performances and trigger a cognitive speed-improvement tradeoff under the novel context. However, there are no consistent cognitive styles that co-varied with different personalities.

9.
Sci Rep ; 11(1): 23593, 2021 12 08.
Artigo em Inglês | MEDLINE | ID: mdl-34880339

RESUMO

A principle of choice in animal decision-making named probability matching (PM) has long been detected in animals, and can arise from different decision-making strategies. Little is known about how environmental stochasticity may influence the switching time of these different decision-making strategies. Here we address this problem using a combination of behavioral and theoretical approaches, and show, that although a simple Win-Stay-Loss-Shift (WSLS) strategy can generate PM in binary-choice tasks theoretically, budgerigars (Melopsittacus undulates) actually apply a range of sub-tactics more often when they are expected to make more accurate decisions. Surprisingly, budgerigars did not get more rewards than would be predicted when adopting a WSLS strategy, and their decisions also exhibited PM. Instead, budgerigars followed a learning strategy based on reward history, which potentially benefits individuals indirectly from paying lower switching costs. Furthermore, our data suggest that more stochastic environments may promote reward learning through significantly less switching. We suggest that switching costs driven by the stochasticity of an environmental niche can potentially represent an important selection pressure associated with decision-making that may play a key role in driving the evolution of complex cognition in animals.


Assuntos
Comportamento de Escolha/fisiologia , Tomada de Decisões/fisiologia , Aprendizagem/fisiologia , Animais , Cognição/fisiologia , Melopsittacus/fisiologia , Reforço Psicológico , Recompensa
10.
Zhongguo Gu Shang ; 34(2): 101-7, 2021 Feb 25.
Artigo em Zh | MEDLINE | ID: mdl-33665994

RESUMO

OBJECTIVE: To compare therapeutic effects of internal fixation with volar locking plate in treating extension and flexion type of distal radius fracture (DRF). METHODS: From January 2015 to June 2018, 103 patients with DRF were retrospectively analyzed. According to original fracture displacement direction, patients were divided into extension fracture(Colles) group and flexion fracture (Smith) group. In Colles fracture group, there were 24 males and 44 females aged from 20 to 79 years old with an average of (59.0±13.4) years old;according to AO classification, 9 patients of type A2, 13 patients of type A3, 16 patientsof type C1, 17 patients of type C2 and 13 patients of type C3;the time from injury to operation ranged from 2 to 9 days with an average of (3.9±0.8) days. In Smith fracture group, there were 15 males and 20 females, aged from 27 to 87 years old with an average of (60.1±15.3) years old;according to AO classification, 4 patienst of A2, 7 patients of A3, 14 patients of C1, 5 patients of C2 and 5 patients of C3;the time from injury to operation ranged from 2 to 6 days with an average of (4.1±0.9) days. Operation time, fracture healing time and postoperative complications were recorded between two groups. Disabilities of arm, shoulder and hand (DASH) score at 6 and 8 weeks, 6 and 8 months were used to evaluate functional recovery of affected limbs during each follow up. Volar tilt, radial inclination and radius height were measured at 8 months after operation. Mayo score was measured at 8 months after operation to evaluate recovery of limb function. RESULTS: All patients were followed up for 8 to 30 months with an average of (14.8±4.3) months, and no difference in follow up between two groups (P> 0.05). There were no statistical differences in operation time, fracture healing time and postoperative complications between two groups(P>0.05). DASH score at 6 and 12 weeks in Colles fracture group were (37.24±5.08) and (19.68±4.55), while in Smith fracture group were (39.05±4.79) and (23.44±4.21);Colles fracture group was better than that of Smith fracture group (P<0.001);while there were no differences in DASH score at 6 and 8 months between two groups (P>0.05). Volar tilt of Smith fracture group (11.1±3.1)° was better than that of Colles fracture group (8.6±4.1) °, and there were no significant difference in radial inclination and radius height between two groups(P>0.05). Also there was no significant difference in Mayo score between two group(P>0.05). CONCLUSION: Patients with Colles fracture and Smith fracture could receive good reduction and fixation through volar locking plate. The radiographic parameters of both groups recovered satisfactorily after operation. Recovery of volar tilt of Smith fracture group is better than that of Colles fracture group, and early recovery function of Colles fracture group is better than that of Smith group, but there is no significant difference in long-term wrist joint function and incidence of postoperative complications between two groups.


Assuntos
Fraturas do Rádio , Adulto , Idoso , Idoso de 80 Anos ou mais , Placas Ósseas , Feminino , Fixação Interna de Fraturas , Humanos , Masculino , Pessoa de Meia-Idade , Fraturas do Rádio/cirurgia , Amplitude de Movimento Articular , Estudos Retrospectivos , Resultado do Tratamento , Articulação do Punho , Adulto Jovem
11.
Sci Rep ; 11(1): 24496, 2021 12 30.
Artigo em Inglês | MEDLINE | ID: mdl-34969948

RESUMO

Among seven species of the order Eulipotyphla (from southern Gansu and northern Sichuan Provinces, Central China) studied cytogenetically, karyotypes of one talpid species, Uropsilus aff. soricipes (2n = 36, NFa = 54), and three soricid species, Chodsigoa hypsibia (2n = 65, NFa = 66), Sorex cansulus (2n = 42, NFa = 64) and Sorex thibetanus (2n = 42, NFa = 60), are described cytogenetically for the first time. All four species are endemic to China with distribution ranges restricted to the Qinghai-Tibet Plateau and adjacent mountain ranges. The Ch. hypsibia karyotype consists of mostly acrocentric autosomes and one metacentric pair of autosomes; besides, a B chromosome was identified. No polymorphism was detected among karyotypes of other species, including shrews Sorex bedfordiae (2n = 26, NFa = 44), Anourosorex squamipes (2n = 48, NFa = 92) and Crocidura suaveolens (2n = 40, NFa = 44). The Chinese shrew mole U. aff. soricipes and three shrew species (S. bedfordiae, Ch. hypsibia and A. squamipes) represent autochthonous fauna of Central/Western China, whereas S. thibetanus, S. cansulus and C. suaveolens belong to phylogenetic groups occurring mostly to the north and west from China; therefore, they should be considered relatively recent colonisers. Thus, considering the relationships of the species within phylogenetic groups, our results on karyotypes are in good agreement with molecular genetic data.


Assuntos
Eulipotyphla/genética , Animais , China , Feminino , Variação Genética , Cariótipo , Masculino , Filogenia , Tibet
12.
BMC Ecol Evol ; 21(1): 194, 2021 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-34689746

RESUMO

BACKGROUND: The boreal forest is one of the largest biomes on earth, supporting thousands of species. The global climate fluctuations in the Quaternary, especially the ice ages, had a significant influence on the distribution of boreal forest, as well as the divergence and evolution of species inhabiting this biome. To understand the possible effects of on-going and future climate change it would be useful to reconstruct past population size changes and relate such to climatic events in the past. We sequenced the genomes of 32 individuals from two forest inhabiting bird species, Hazel Grouse (Tetrastes bonasia) and Chinese Grouse (T. sewerzowi) and three representatives of two outgroup species from Europe and China. RESULTS: We estimated the divergence time of Chinese Grouse and Hazel Grouse to 1.76 (0.46-3.37) MYA. The demographic history of different populations in these two sibling species was reconstructed, and showed that peaks and bottlenecks of effective population size occurred at different times for the two species. The northern Qilian population of Chinese Grouse became separated from the rest of the species residing in the south approximately 250,000 years ago and have since then showed consistently lower effective population size than the southern population. The Chinese Hazel Grouse population had a higher effective population size at the peak of the Last Glacial Period (approx. 300,000 years ago) than the European population. Both species have decreased recently and now have low effective population sizes. CONCLUSIONS: Combined with the uplift history and reconstructed climate change during the Quaternary, our results support that cold-adapted grouse species diverged in response to changes in the distribution of palaeo-boreal forest and the formation of the Loess Plateau. The combined effects of climate change and an increased human pressure impose major threats to the survival and conservation of both species.


Assuntos
Mudança Climática , Galliformes , Animais , Ecossistema , Galliformes/genética , Humanos , Densidade Demográfica , Sequenciamento Completo do Genoma
13.
Mol Phylogenet Evol ; 55(3): 952-67, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20102744

RESUMO

In this paper we provide a molecular phylogeny based on three mitochondrial and three nuclear markers for all long-tailed tit species of the genus Aegithalos including several doubtful subspecies (17 taxa) plus three close allies of SE Asian Leptopoecile and North American Psaltriparus. Genus Aegithalos is divided into three major clades, two of them showing only minor differentiation. Separation of two mitchondrial haploytpe clusters in the N Palearctic Long-tailed Tit, Ae. caudatus, was dated back to the Late Pleistocene, however, descendants from both lineages underwent a rapid post-Pleistocene range expansion and largely mixed over the entire distribution area. The Chinese populations of the glaucogularis subspecies group represent a slightly earlier Pleistocene split from the Ae. caudatus clade. Genetic differentiation among several doubtful SE Asian species taxa on the sister clade of the latter N Palearctic/Chinese clade matches the intraspecific differentiation within Ae. caudatus. Unexpectedly, cytochrome-b distances among Himalayan Ae. iouschistos (including the subspecies bonvaloti from China and sharpei from Myanmar) and the Chinese endemic Ae. fuliginosus range at approximately 0.5% and apparently all these extant populations separated only very recently during late Pleistocene times, too. W Himalayan Ae. niveogularis clearly appeared as the sister species of the latter taxon assemblage. Unlike the two latter major clades, Ae. concinnus shows strong intraspecific differentiation with cyt-b distances as high as 6% among two Himalayan populations of ssp. iredalei, ssp. manipurensis from Myanmar and a fourth lineage from SW and SC China including ssp. talifuensis and nominate concinnus. A sister-group relationship between all Ae. concinnus and Ae. leucogenys was strongly supported. N American bushtits of genus Psaltriparus represent the sister clade to Palearctic genus Aegithalos, including a clear split between the minimus and the plumbeus subspecies group which was again dated back to Pleistocene times. The two tit-warbler species of genus Leptopoecile are strongly differentiated from one another and represent an early split from the Aegithalidae tree.


Assuntos
Evolução Molecular , Passeriformes/classificação , Filogenia , Animais , Núcleo Celular/genética , China , DNA Mitocondrial/genética , Geografia , Haplótipos , Modelos Genéticos , América do Norte , Passeriformes/genética , Análise de Sequência de DNA
14.
Behav Processes ; 178: 104158, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32497556

RESUMO

Recognizing and rejecting foreign eggs is one of the most effective anti-parasite strategies for hosts in avian brood parasitism. Studies have shown that most cuckoo (Cuculus spp.) hosts have evolved egg recognition abilities. Although some open-nesting birds, especially thrushes belonging to the family Turdidae, are rarely parasitized by cuckoos, they still have high egg recognition ability. This evolutionary selection pressure on egg recognition is currently controversial. Previous studies on egg recognition of thrushes have mainly been carried out in Europe in a single-cuckoo system. In this study, chestnut thrushes (Turdus rubrocanus), which are distributed in a multiple-cuckoo system in China, were used to test their egg rejection and egg recognition mechanism. Our results showed that chestnut thrushes had a rejection rate of 54 % for non-mimetic blue model eggs, showing moderate egg recognition ability. Their egg recognition was true recognition, which relied on a memory template; chestnut thrushes could accurately reject foreign eggs in their nests. This study added the second case to report the egg recognition mechanism of thrushes in the Turdidae family and showed that the evolution of egg recognition ability of chestnut thrushes was likely a retained anti-parasitic strategy because of being parasitized by cuckoos in the past.


Assuntos
Aves Canoras , Animais , China , Ovos , Europa (Continente) , Interações Hospedeiro-Parasita , Comportamento de Nidação , Óvulo
15.
Ecol Evol ; 10(17): 9283-9300, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32953061

RESUMO

Encompassing some of the major hotspots of biodiversity on Earth, large mountain systems have long held the attention of evolutionary biologists. The region of the Qinghai-Tibet Plateau (QTP) is considered a biogeographic source for multiple colonization events into adjacent areas including the northern Palearctic. The faunal exchange between the QTP and adjacent regions could thus represent a one-way street ("out of" the QTP). However, immigration into the QTP region has so far received only little attention, despite its potential to shape faunal and floral communities of the QTP. In this study, we investigated centers of origin and dispersal routes between the QTP, its forested margins and adjacent regions for five clades of alpine and montane birds of the passerine superfamily Passeroidea. We performed an ancestral area reconstruction using BioGeoBEARS and inferred a time-calibrated backbone phylogeny for 279 taxa of Passeroidea. The oldest endemic species of the QTP was dated to the early Miocene (ca. 20 Ma). Several additional QTP endemics evolved in the mid to late Miocene (12-7 Ma). The inferred centers of origin and diversification for some of our target clades matched the "out of Tibet hypothesis' or the "out of Himalayas hypothesis" for others they matched the "into Tibet hypothesis." Three radiations included multiple independent Pleistocene colonization events to regions as distant as the Western Palearctic and the Nearctic. We conclude that faunal exchange between the QTP and adjacent regions was bidirectional through time, and the QTP region has thus harbored both centers of diversification and centers of immigration.

16.
Sci Rep ; 10(1): 17673, 2020 10 19.
Artigo em Inglês | MEDLINE | ID: mdl-33077778

RESUMO

Nature reserves play an extraordinarily important role in conserving animal populations and their habitats. However, landscape change and unreasonable zoning designations often render these protected areas inadequate. Therefore, regular evaluation of the efficacy of protected lands is critical for maintaining and improving management strategies. Using species distribution models and GAP analysis, we assessed the changes in suitable habitat for the Brown Eared-pheasant (Crossoptilon mantchuricum) in two Chinese nature reserves between 1995 and 2013. Our results showed that the habitat suitability of Brown Eared-pheasant has changed dramatically during this period, and fragmentation analyses showed an increase in concentration area and decrease in patch area. In particular, our findings show that the national nature reserves need to adjust their ranges to ensure the conservation of this flagship species. Our study further provides a new viewpoint for evaluating the efficacy of protected lands, particularly in highly urbanized regions where conservation goals must be balanced with changing landscapes.


Assuntos
Conservação dos Recursos Naturais , Espécies em Perigo de Extinção , Galliformes , Animais , China , Conservação dos Recursos Naturais/métodos , Urbanização
17.
Curr Zool ; 66(1): 29-37, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-32467702

RESUMO

Nest survival is a vital component of breeding success, and affects population dynamics, as the loss of nests is the main cause of reproductive failure in birds. To identify key factors for the conservation of Chinese grouse Tetrastes sewerzowi, we tested the effects of nest concealment, nest age, nesting season, and habitat edge on nest daily survival rate (DSR) of Chinese grouse using 54 nests found at Lianhuashan Nature Reserve, Gansu, China, 2009-2012. Moreover, we controlled for the effect of research activity by testing the effect of nest checks on DSR. Overall, mammal predation caused 93% of nest failures. DSR was 0.986 ± 0.0038 in the constant model and the probability of a nest with a full clutch of 6 eggs surviving the entire 40-day nesting period was 0.526 ± 0.090. DSR decreased with nest age and nesting season (from 19 May to 3 July). Mammals instead of avian predators being responsible for most nest failures suggest that nest sites might be selected to avoid visual avian predators, but not olfactory mammalian predators, and the decreasing trend of DSR with nest age and nesting season could attribute to an additive exposure effect. Moreover, nest checks conducted by investigators significantly lowered nest DSR, especially during the late period of nesting season and for older nests. Mammalian predators might locate the nest site by following the investigator's odor. Based on our results, we suggest that the late incubation stage is a particularly vulnerable period for nest survival of Chinese grouse and those researchers should adjust their activities around nests to balance the need of acquiring accurate data and decreasing nest predation risk.

18.
Chin J Traumatol ; 12(5): 299-301, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19788849

RESUMO

OBJECTIVE: To observe the early clinical outcomes of the internal fixation with distal radius volar locking compression plate (LCP) in treatment of distal clavicle fracture. METHODS: Six patients with unilateral distal clavicle fractures, identified as type II according to Neer classification system, including 4 males and 2 females, were treated with open reduction and internal fixation using a distal radius volar LCP. Bone union was evaluated by routine X-ray radiography, and shoulder joint function were assessed by Constant score system. RESULTS: All fractures achieved bone union at 6 to 8 weeks postoperatively, and Constant scores ranged from 95 to 100 at the postoperative 10 to 12 weeks. CONCLUSION: Fixation of distal clavicle fracture with distal radius volar LCP demonstrates excellent effects of bone union with rarely early complications, thus providing a new technique to treat distal clavicle fracture.


Assuntos
Placas Ósseas , Clavícula/lesões , Fixação Interna de Fraturas/instrumentação , Fraturas Ósseas/cirurgia , Rádio (Anatomia)/cirurgia , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
19.
Science ; 363(6423): 166-167, 2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30630929

RESUMO

Darwin proposed that mate choice might contribute to the evolution of cognitive abilities. An open question is whether observing the cognitive skills of an individual makes it more attractive as a mate. In this study, we demonstrated that initially less-preferred budgerigar males became preferred after females observed that these males, but not the initially preferred ones, were able to solve extractive foraging problems. This preference shift did not occur in control experiments in which females observed males with free access to food or in which females observed female demonstrators solving these extractive foraging problems. Our results suggest that direct observation of problem-solving skills increases male attractiveness and that this could contribute to the evolution of the cognitive abilities underlying such skills.


Assuntos
Cognição , Preferência de Acasalamento Animal , Melopsittacus/fisiologia , Resolução de Problemas , Animais , Comportamento Apetitivo , Proteínas Quinases Dependentes de GMP Cíclico , Proteínas de Drosophila , Feminino , Masculino
20.
Zhonghua Wai Ke Za Zhi ; 46(7): 493-6, 2008 Apr 01.
Artigo em Zh | MEDLINE | ID: mdl-18785556

RESUMO

OBJECTIVE: To explorer the effectiveness of enriched bone marrow stem cells technique for lumbar fusion. METHODS: With the randomization and control principles, 2 graft materials [Enrichment bone marrow mesenchymal stem cells hybridized with beta-tri calcium phosphate (composite graft group), autologous iliac crest bone graft (autograft group)] were compared in posterior lumbar fusion procedures. 56 patients with degenerative disc disease, lumbar instability or spinal stenosis, were included. The volume of cells suspension in pre- and post-enrichment and the number of nucleated cells (NCs) were identified. The number of osteoprogenitor cells was estimated by counting the colony-forming units which express alkaline phosphatase (CFUs/ALP+). Then the efficiency of the enrichment was evaluated. Clinical follow-up with roentgenogram and Oswestry scale scores was performed for outcome evaluation. RESULTS: (249 +/- 31) ml bone marrow per patient from bilateral iliac crests was aspirated peri-operatively. About (43 +/- 11) ml enriched bone marrow was collected. The number of NCs was concentrated from (15.9 +/- 3.3) x 10(6)/ml to (44.1 +/- 10.8) x 10(6)/ml, CFUs/ALP+ was significantly increased from (118 +/- 86)/ml to(486 +/- 305)/ml. The follow-up was about (26.3 +/- 7.5) months. There was no significant differences in age, gender, disease and fusion segments between the two groups. The fusion rate was 93.3% and 96.2% for composite graft group and autograft group, respectively (chi2 = 0.2146, P = 0.6432). There was no difference in operation time between the two group (t = 0.5243, P = 0.6022), but blood loss in composite graft group was more than that in autograft group (t = 6.4664, P < 0.01). Cell salvage for auto-transfusion could transfuse back half of the blood loss during operation. No hematoma or chronic soreness in the bone marrow donor sites of composite graft group occurred, but a little exudation or moderate swelling in the wound happened in 4 cases which disappeared under medical treatment. Meanwhile, 15.4% patients had hematoma in the iliac bone donor site and 26.9% patients had chronic soreness, but no case had wound problem in autograft group. As for Oswestry scale scores, there was no significant difference between the two groups. CONCLUSIONS: The enrichment technique of autologous bone marrow stem cells can greatly increase the concentration of MSCs. It is a rapid and safe method used peri-operatively. The composite material of enriched MSCs and porous beta-TCP is a good bone substitute in posterior spinal fusion.


Assuntos
Substitutos Ósseos , Vértebras Lombares/cirurgia , Fusão Vertebral/métodos , Transplante de Células-Tronco , Adulto , Idoso , Transplante Ósseo/métodos , Fosfatos de Cálcio , Feminino , Seguimentos , Humanos , Ílio/transplante , Masculino , Pessoa de Meia-Idade , Fusão Vertebral/instrumentação , Transplante Autólogo , Resultado do Tratamento
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