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1.
Heredity (Edinb) ; 131(5-6): 374-386, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37806995

RESUMO

Using genetic information to develop and implement conservation programs is vital for maintaining biodiversity and ecosystem resilience. Evaluation of the genetic variability within and among remnant populations can inform management of both natural and translocated populations to maximise species' adaptive potential, mitigate negative impacts of inbreeding, and subsequently minimise risk of extinction. Here we use reduced representation sequencing to undertake a genetic assessment of the golden bandicoot (Isoodon auratus), a threatened marsupial endemic to Australia. The currently recognised taxon consists of three subspecies distributed among multiple natural and translocated populations. After confirming the genetic distinctiveness of I. auratus from two closely related taxa, I. fusciventer and I. macrourus, we identified four genetic clusters within I. auratus. These clusters exhibited substantial genetic differentiation (pairwise FST values ranging from 0.18 to 0.65, pairwise DXY ranging from 0.1 to 0.168), reflecting long-term isolation of some populations on offshore islands and the influence of genetic drift. Mainland natural populations in the Kimberley region had the highest genetic diversity and the largest contribution to overall allelic and gene diversity compared to both natural and translocated island populations. A population translocated to Guluwuru Island in the Northern Territory had the lowest genetic diversity. Our data suggest that island populations can appear genetically unique due to genetic drift and this needs to be taken into account when considering genetic diversity in conservation efforts to maintain overall genetic diversity of the species. We effectively demonstrate how genomic information can guide practical conservation planning, especially when declining species are represented by multiple isolated populations.


Assuntos
Variação Genética , Genética Populacional , Ecossistema , Metagenômica , Deriva Genética , Conservação dos Recursos Naturais
2.
Zoo Biol ; 42(1): 98-106, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35815730

RESUMO

Captive chimpanzees (Pan troglodytes) mature earlier in body mass and have a greater growth rate compared to wild individuals. However, relatively little is known about how growth parameters compare between chimpanzees living in different captive environments. To investigate, body mass was measured in 298 African sanctuary chimpanzees and was acquired from 1030 zoological and 442 research chimpanzees, using data repositories. An analysis of covariance, adjusting for age, was performed to assess same-sex body mass differences between adult sanctuary, zoological, and research populations. Piecewise linear regression was performed to estimate sex-specific growth rates and the age at maturation, which were compared between sexes and across populations using extra-sum-of-squares F tests. Adult body mass was greater in the zoological and resarch populations compared to the sanctuary chimpanzees, in both sexes. Male and female sanctuary chimpanzees were estimated to have a slower rate of growth compared with their zoological and research counterparts. Additionally, male sanctuary chimpanzees were estimated to have an older age at maturation for body mass compared with zoological and research males, whereas the age at maturation was similar across female populations. For both the zoological and research populations, the estimated growth rate was greater in males compared to females. Together, these data contribute to current understanding of growth and maturation in this species and suggest marked differences between the growth patterns of chimpanzees living in different captive environments.


Assuntos
Animais Selvagens , Pan troglodytes , Animais , Masculino , Feminino , Animais de Zoológico , Caracteres Sexuais
3.
Environ Entomol ; 50(2): 405-409, 2021 04 23.
Artigo em Inglês | MEDLINE | ID: mdl-33439991

RESUMO

Temperature affects all aspects of ectotherm ecology, behavior, and physiology. Descriptions of thermal ecology are important for understanding ecology in changing thermal environments. Both laboratory and field estimates are important for understanding thermal ecology. Rabidosa rabida (Walckenaer 1837) (Araneae: Lycosidae) is a large wolf spider with some natural history, including laboratory estimates of thermal preference, tolerance, and performance, reported in the scientific literature. Laboratory tests suggest the active choice of temperature environment. To test published estimates of thermal ecology from the laboratory, we took body temperature measurements of mature spiders in the field nocturnally and diurnally using a FLIR camera in July 2019. We made comparisons between sexes and activity periods using field observations. We compared these measurements with the published values for thermal preferences and thermal maximum and with mean weather station data. Observed field temperatures differed significantly from published preference, but not from mean temperature from a local weather station. This suggests that this species is thermoconforming rather than actively thermoregulating. Reported thermal preference fell between the diurnal and nocturnal mean measurements closer to the diurnal than nocturnal temperatures. These field observations show how important it is to make field observations for physiology and thermal ecology. Maximum observed diurnal temperatures closely approached the published critical thermal maximum. We observed spiders performing behaviors such as hunting and feeding in conditions well above published thermal preference and near-critical high temperature. These observations suggest that R. rabida is thermoconforming in this limited period but does not rule out that they might thermoregulate in certain situations.


Assuntos
Temperatura Corporal , Aranhas , Animais , Regulação da Temperatura Corporal , Ecologia , Laboratórios , Temperatura
4.
PLoS One ; 12(8): e0180139, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28767648

RESUMO

The Migidae are a family of austral trapdoor spiders known to show a highly restricted and disjunct distribution pattern. Here, we aim to investigate the phylogeny and historical biogeography of the group, which was previously thought to be vicariant in origin, and examine the biogeographic origins of the genus Moggridgea using a dated multi-gene phylogeny. Moggridgea specimens were sampled from southern Australia and Africa, and Bertmainus was sampled from Western Australia. Sanger sequencing methods were used to generate a robust six marker molecular dataset consisting of the nuclear genes 18S rRNA, 28S rRNA, ITS rRNA, XPNPEP3 and H3 and the mitochondrial gene COI. Bayesian and Maximum Likelihood methods were used to analyse the dataset, and the key dispersal nodes were dated using BEAST. Based on our data, we demonstrate that Moggridgea rainbowi from Kangaroo Island, Australia is a valid member of the otherwise African genus Moggridgea. Molecular clock dating analyses show that the inter-specific divergence of M. rainbowi from African congeners is between 2.27-16.02 million years ago (Mya). This divergence date significantly post-dates the separation of Africa from Gondwana (95 Mya) and therefore does not support a vicariant origin for Australian Moggridgea. It also pre-dates human colonisation of Kangaroo Island, a result which is further supported by the intra-specific divergence date of 1.10-6.39 Mya between separate populations on Kangaroo Island. These analyses provide strong support for the hypothesis that Moggridgea colonised Australia via long-distance trans-Indian Ocean dispersal, representing the first such documented case in a mygalomorph spider.


Assuntos
Distribuição Animal , Especiação Genética , Filogenia , Aranhas/classificação , África , Aminopeptidases/genética , Animais , Austrália , Teorema de Bayes , Citocromos b/genética , DNA/química , DNA/genética , DNA Mitocondrial/química , DNA Mitocondrial/genética , Histonas/genética , Oceano Índico , Filogeografia , RNA Ribossômico 18S/genética , RNA Ribossômico 28S/genética , Análise de Sequência de DNA , Aranhas/genética
5.
PLoS One ; 7(10): e47549, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23071823

RESUMO

In the past decade the interest surrounding the role of recombination in speciation has been re-kindled by a new generation of chromosomal speciation models that invoke the recombination-suppression properties of some types of chromosomal rearrangement. A common prediction of recombination-suppression models is that gene exchange between diverging populations will be more restricted in regions of the genome that experience low recombination. We carried out a genome scan of three chromosomal races of the grasshopper Vandiemenella viatica (Orthoptera: Morabinae), occurring on Kangaroo Island, South Australia, using 1517 AFLP loci, with a view to elucidating the roles that selection and chromosomal variation have played in the formation of these taxa. An analysis of molecular variance demonstrated that chromosomal race accounted for a significant proportion of the genetic variance in the total dataset, which concurred with the findings of an earlier study. Sampling across one previously-identified hybrid zone, and the identification of outlier loci between parental races allowed us to establish that, in admixed populations, outlier loci which potentially pre-date the isolation of populations of races on Kangaroo Island exhibit higher levels of linkage disequilibrium with each other than putatively neutral loci. In turn this suggests that they might reside within genomic regions of low recombination, or be closely linked with each other.


Assuntos
Cromossomos/genética , Variação Genética , Genoma/genética , Gafanhotos/genética , Desequilíbrio de Ligação/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Especiação Genética , Genética Populacional , Gafanhotos/classificação , Austrália do Sul , Especificidade da Espécie
6.
Res Sports Med ; 20(2): 129-41, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22458829

RESUMO

The aim of this study was to investigate differences in blood lactate accumulation following 10 and 20 sec of maximal cycle ergometer exercise. Body mass, stature, and age of the group was determined prior to testing (82.57 ± 5.94 kg 177 ± 5.94 cm and 21.42 ± 1.61 yrs, respectively). Eight male rugby union players performed two maximal sprints in a random fashion of 10 and 20 sec duration on a cycle ergometer. During the 10 and 20 sec trial, blood lactate levels measured were as follows 1.58 ± 0.78, 4.43 ± 1.4, and 3.5 ± 1.2 mmol.l⁻¹ vs. 1.72 ± 0.65, 6.14 ± 2, and 5.68 ± 2.22 mmol.l⁻¹, respectively. Differences were found (P < 0.01) from rest to 5 and 10 min postexercise in both groups. Differences in concentration also were found between groups at both postexercise stages (P < 0.01). The reduction in blood lactate concentrations observed between the 5 to 10 min recovery stages were 0.91 ± 0.58 mmol.l⁻¹ vs. 0.46 ± 0.48 mmol.l⁻¹ following 10 and 20 sec of maximal exercise, respectively (P > 0.05). The concentrations observed are interesting and may influence recovery time and subsequent exercise performance.


Assuntos
Ergometria/instrumentação , Tolerância ao Exercício/fisiologia , Ácido Láctico/sangue , Corrida/fisiologia , Fatores Etários , Análise de Variância , Índice de Massa Corporal , Intervalos de Confiança , Fadiga , Glicólise , Humanos , Masculino , Fatores de Tempo , Adulto Jovem
8.
Ann Thorac Surg ; 77(1): 29-35, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14726029

RESUMO

BACKGROUND: Our purpose was to document our experience with early recruitment of congenitally disconnected pulmonary arteries and to assess subsequent pulmonary artery growth and function. METHODS: Patients born in the 10-year period from 1989 to 1999 with a disconnected pulmonary artery diagnosed in infancy and treated in our unit were studied. To be included patients had nonconfluent pulmonary arteries with one or both completely disconnected from the main pulmonary artery. This series did not include patients with acquired stenosis causing occlusion of a pulmonary artery. Echocardiography, cardiac catheterization, MRI, lung perfusion scans, and intraoperative assessment were used to gauge pulmonary artery growth and function. RESULTS: Seven patients with a disconnected pulmonary artery associated with intracardiac conotruncal congenital cardiac disease underwent successful early surgical recruitment of the affected pulmonary artery at 3 months of age or younger. Median follow-up from date of first operation was 4.2 years (range, 1.6 to 13.4). All 7 patients had postrecruitment lung perfusion scans showing a mean of 44% (range, 27% to 78%) of total pulmonary flow through the affected lung. Significant growth in the diameter of the recruited native pulmonary artery was demonstrated in all patients. There were no deaths reported in our series to date. CONCLUSIONS: The rare possibility of a congenitally disconnected pulmonary artery needs to be considered in all patients with a conotruncal cardiac anomaly. To facilitate surgical correction, ensure subsequent growth of the pulmonary artery, and optimize associated lung development, early diagnosis and surgical recruitment is recommended.


Assuntos
Artéria Pulmonar/anormalidades , Artéria Pulmonar/cirurgia , Anormalidades Congênitas/epidemiologia , Seguimentos , Humanos , Incidência , Lactente , Recém-Nascido , Indução de Remissão , Procedimentos Cirúrgicos Vasculares/métodos
9.
Mol Phylogenet Evol ; 27(2): 212-22, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12695086

RESUMO

Allodapine bees are most diverse in Africa but are distributed throughout the Old World tropical and Austral regions. They are considered useful for studies into the evolution of social behaviour since they exhibit the full range of social organisation from solitary to highly eusocial (sensu; ). Five genera are found in Australia, namely Braunsapis, Exoneurella, Exoneura, Brevineura, and Inquilina. Sociality and life histories are well documented for the exoneurine genera (review in ) and Inquilina is an obligate social parasite of species of Exoneura (). In this paper, maximum parsimony and maximum likelihood methods using molecular sequence data from two mitochondrial gene regions (cyt b and COI) and a single nuclear gene region (EF-1alpha) are used to reconstruct phylogenetic relationships of the Australian allodapine genera. Results suggest that the exoneurine group (Brevineura, Exoneurella, and Exoneura+Inquilina) diverged very rapidly and are monophyletic to the exclusion of other (primarily African) allodapine genera. A clade containing Australian species of Braunsapis is also monophyletic to the exclusion of African congeners. Braunsapis is not phylogenetically close to, and is a more derived group than the exoneurine group and probably came to occupy the Australian plate via a later dispersal through the southern Asian region. It is unclear at this point how the exoneurine group came to occupy the Australian plate and possible scenarios are discussed.


Assuntos
Abelhas/classificação , Filogenia , Animais , Austrália , Composição de Bases , Abelhas/genética , Primers do DNA/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Evolução Molecular , Geografia , Funções Verossimilhança , Fator 1 de Elongação de Peptídeos/genética
10.
Ir J Psychol Med ; 20(4): 115-118, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30308719

RESUMO

OBJECTIVES: A quarter of people with schizophrenia may be classed as 'treatment-resistant'. Clozapine is an antipsychotic that holds significant potential benefit for this patient group and has recently been recommended by the National Institute for Clinical Excellence. Early discontinuation is common. This study explores the factors that predict such discontinuation. METHOD: This retrospective cohort design was carried out on two hundred and one people with treatment resistant schizophrenia who had commenced clozapine between 1990 and 1997 identified from the Clozaril Patient Monitoring Service (CPMS) in Northern Ireland. Clinical and socio-demographic data was collected for three years before and after commencement on clozapine. Kaplan Meier survival analyses were conducted to identify differences in discontinuation rates according to a range of variables. RESULTS: Forty-five per cent of patients had discontinued before three years. No difference in rates were found between men and women, nor whether side-effects were reported or not Patients who had commenced clozapine at an older age had significantly higher cessation rates. People who had started clozapine at age 50+ were four times more likely to stop taking clozapine within three years than people aged between 17-29 years. CONCLUSIONS: Differences in continuation rates may be due to a number of factors. Treatment resistance may increase with age, side-effects may worsen or patient willingness to tolerate such effects may reduce. Alternatively, clinicians may be more anxious about prescribing clozapine as levels of co-morbidity increase. Further research is required to identify precise reasons and develop interventions to reduce discontinuation rates among older patients.

11.
Evolution ; 57(12): 2819-34, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-14761060

RESUMO

Calcrete aquifers in arid inland Australia have recently been found to contain the world's most diverse assemblage of subterranean diving beetles (Coleoptera: Dytiscidae). In this study we test whether the adaptive shift hypothesis (ASH) or the climatic relict hypothesis (CRH) is the most likely mode of evolution for the Australian subterranean diving beetles by using a phylogeny based on two sequenced fragments of mitochondrial genes (CO1 and 16S-tRNA-ND1) and linearized using a relaxed molecular clock method. Most individual calcrete aquifers contain an assemblage of diving beetle species of distantly related lineages and/or a single pair of sister species that significantly differ in size and morphology. Evolutionary transitions from surface to subterranean life took place in a relatively small time frame between nine and four million years ago. Most of the variation in divergence times of the sympatric sister species is explained by the variation in latitude of the localities, which correlates with the onset of aridity from the north to the south and with an aridity maximum in the Early Pliocene (five mya). We conclude that individual calcrete aquifers were colonized by several distantly related diving beetle lineages. Several lines of evidence from molecular clock analyses support the CRH, indicating that all evolutionary transitions took place during the Late Miocene and Early Pliocene as a result of aridification.


Assuntos
Adaptação Biológica , Besouros/genética , Mergulho/fisiologia , Evolução Molecular , Filogenia , Animais , Austrália , Sequência de Bases , Teorema de Bayes , Besouros/fisiologia , Primers do DNA , DNA Mitocondrial/genética , Clima Desértico , Água Doce , Geografia , Funções Verossimilhança , Modelos Genéticos , Dados de Sequência Molecular , Análise de Sequência de DNA
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