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1.
Syst Biol ; 68(6): 859-875, 2019 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-31140573

RESUMO

Theory predicts that sexually dimorphic traits under strong sexual selection, particularly those involved with intersexual signaling, can accelerate speciation and produce bursts of diversification. Sexual dichromatism (sexual dimorphism in color) is widely used as a proxy for sexual selection and is associated with rapid diversification in several animal groups, yet studies using phylogenetic comparative methods to explicitly test for an association between sexual dichromatism and diversification have produced conflicting results. Sexual dichromatism is rare in frogs, but it is both striking and prevalent in African reed frogs, a major component of the diverse frog radiation termed Afrobatrachia. In contrast to most other vertebrates, reed frogs display female-biased dichromatism in which females undergo color transformation, often resulting in more ornate coloration in females than in males. We produce a robust phylogeny of Afrobatrachia to investigate the evolutionary origins of sexual dichromatism in this radiation and examine whether the presence of dichromatism is associated with increased rates of net diversification. We find that sexual dichromatism evolved once within hyperoliids and was followed by numerous independent reversals to monochromatism. We detect significant diversification rate heterogeneity in Afrobatrachia and find that sexually dichromatic lineages have double the average net diversification rate of monochromatic lineages. By conducting trait simulations on our empirical phylogeny, we demonstrate that our inference of trait-dependent diversification is robust. Although sexual dichromatism in hyperoliid frogs is linked to their rapid diversification and supports macroevolutionary predictions of speciation by sexual selection, the function of dichromatism in reed frogs remains unclear. We propose that reed frogs are a compelling system for studying the roles of natural and sexual selection on the evolution of sexual dichromatism across micro- and macroevolutionary timescales.


Assuntos
Anuros/classificação , Filogenia , Pigmentação , África , Animais , Anuros/fisiologia , Evolução Biológica , Feminino , Masculino , Caracteres Sexuais
2.
Mol Phylogenet Evol ; 136: 183-195, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30965125

RESUMO

Trachylepis (Mabuyinae) includes ∼80 species of fully-limbed skinks found primarily in Africa and Madagascar, but a robust species-level phylogeny for this genus is lacking and this impedes studies on a wide-range of topics from biogeography to character evolution. Trachylepis and its close relatives (which together form the Mabuya group or Mabuyinae) are notable in that they have undergone multiple transitions and remarkable specializations in their reproductive modes. A Trachylepis phylogeny will be particularly useful for investigating reproductive evolution, because it includes species that exhibit oviparity, viviparity, and bimodal parity (species with both oviparous and viviparous populations). We sequenced DNA at four mitochondrial and five nuclear loci for 67 (∼84% of) Trachylepis species to infer a phylogeny for this genus. We performed stochastic character mapping of parity mode under a variety of parity mode transition models to infer ancestral parity mode states and the number and type of parity mode transitions. We recovered a strongly supported phylogeny of Trachylepis that is generally consistent with earlier phylogenetic studies. The best-fit model of reproductive mode evolution supports an oviparous ancestor for Trachylepis, and supports at least three viviparity to oviparity transitions. We compared parity mode evolution under the overall best-fit model (no constraints on parity mode transitions) to the best-fit model among the subset of models that assume viviparity to oviparity transitions are impossible. Our results support a model of reproductive evolution that allows for reversibility from viviparity to oviparity, a process that is not generally accepted. Alternatively, the best-fit model of evolution among the set of models that eliminate reversals from viviparity to oviparity suggests that bimodal reproduction may have persisted for millions of years within multiple lineages.


Assuntos
Lagartos/classificação , Filogenia , África , Animais , Sequência de Bases , Feminino , Loci Gênicos , Geografia , Lagartos/genética , Madagáscar , Reprodução/fisiologia , Especificidade da Espécie , Processos Estocásticos , Temperatura
3.
Mol Phylogenet Evol ; 130: 357-365, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30366085

RESUMO

The African green and bush snakes of the genus Philothamnus currently comprises 21 species and three subspecies and occurs throughout sub-Saharan Africa. The genus has been the subject of previous taxonomic revisions based on traditional morphological characters and limited genetic assessment, and may not reflect their evolutionary history. Indeed, previous findings based on phylogenetics show discordant results of interspecific relationships and question the monophyly of the genus, although taxon sampling has been limited to date. We investigated phylogenetic affinities within Philothamnus with more inclusive genetic and geographical sampling, with the aim of better understanding their evolutionary history, so that future taxonomic revision of Philothamnus can be better informed. Species relationships were examined within a phylogenetic context and sampling included 133 ingroup samples from 16 taxa. Phylogenies were constructed in Bayesian and likelihood frameworks using three mitochondrial (16S, cyt b and ND4) and two nuclear (c-mos and RAG1) markers. Competing hypotheses relating to the monophyly of the genus were tested with a Shimodaira-Hasegawa test. To examine species boundaries, Bayesian General Mixed Yule-Coalescent Model and multi-rate Poisson Tree Processes analyses were conducted. In addition, a barcoding approach was used to further clarify species-level relationships by comparing frequency distributions between intra- and interspecific sequence divergence. The genus was recovered as monophyletic; however, species-delimitation results suggest that the current taxonomy does not reflect the evolutionary history of this group. For example, Philothamnus s. semivariegatus is paraphyletic, with at least four distinct clades. Philothamnus carinatus consists of two cryptic (sister) lineages from Central and West Africa that are deeply divergent, suggesting a long history of isolation between those regions. Furthermore, the subspecies P. n. natalensis and P. n. occidentalis show strong support for species-level divergence, which reflects their morphological and ecological differences. Accordingly, we elevate P. occidentalisnov. comb. to a full species. A fully informed taxonomic revision of these taxa will require additional morphological and ecological data for corroboration, but it seems that the morphological characters (e.g. scalation, dentition) used to describe these species to date are labile within and between species. This most likely has clouded our understanding of the species boundaries within the genus. Our phylogeny and species-delimitation analyses should provide a sounder framework for taxonomy, but may also prove useful toward understanding the morphological adaptations of these species to their respective habitats.


Assuntos
Colubridae/genética , Variação Genética , África Ocidental , Animais , Teorema de Bayes , Geografia , Funções Verossimilhança , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
4.
Trans Am Clin Climatol Assoc ; 130: 166-172, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31516180

RESUMO

I and my colleagues designed and implemented a longitudinal faculty development program to improve humanistic teaching and role modeling at 30 medical schools involving more than 1,000 faculty members and 50 local facilitators. Evaluation demonstrated that participating faculty members who completed our program were superior humanistic teachers compared to controls as rated by their learners on a validated questionnaire. Participants were also sufficiently engaged to attend 80% or more of the curricular sessions with few dropouts, indicating the feasibility and generalizability of the program. Preliminary analysis of participants' personal narratives at the beginning compared to the end of our program suggested advancement in professional identity formation. I provide examples of the narratives and discuss future studies addressing this topic.


Assuntos
Currículo , Empatia , Docentes de Medicina/educação , Humanismo , Papel Profissional , Desenvolvimento de Pessoal/métodos , Humanos , Desenvolvimento de Programas , Avaliação de Programas e Projetos de Saúde , Identificação Social , Ensino
5.
Mol Phylogenet Evol ; 127: 288-303, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29551523

RESUMO

Members of the snake subfamily Aparallactinae occur in various habitats throughout sub-Saharan Africa. The monophyly of aparallactine snakes is well established, but relationships within the subfamily are poorly known. We sampled 158 individuals from six of eight aparallactine genera in sub-Saharan Africa. We employed concatenated gene-tree analyses, divergence dating approaches, and ancestral-area reconstructions to infer phylogenies and biogeographic patterns with a multi-locus data set consisting of three mitochondrial (16S, cyt b, and ND4) and two nuclear genes (c-mos and RAG1). As a result, we uncover several cryptic lineages and elevate a lineage of Polemon to full species status. Diversification occurred predominantly during the Miocene, with a few speciation events occurring subsequently in the Pliocene and Pleistocene. Biogeographic analyses suggested that the Zambezian biogeographic region, comprising grasslands and woodlands, facilitated radiations, vicariance, and dispersal for many aparallactines. Moreover, the geographic distributions of many forest species were fragmented during xeric and cooler conditions, which likely led to diversification events. Biogeographic patterns of aparallactine snakes are consistent with previous studies of other sub-Saharan herpetofauna.


Assuntos
Clima Desértico , Lagartos/anatomia & histologia , Lagartos/classificação , Filogenia , Filogeografia , África Subsaariana , Animais , DNA Mitocondrial/genética , Funções Verossimilhança , Lagartos/genética , Serpentes/anatomia & histologia , Serpentes/genética
6.
J Gen Intern Med ; 33(7): 1092-1099, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29740787

RESUMO

BACKGROUND: Changes in the organization of medical practice have impeded humanistic practice and resulted in widespread physician burnout and dissatisfaction. OBJECTIVE: To identify organizational factors that promote or inhibit humanistic practice of medicine by faculty physicians. DESIGN: From January 1, 2015, through December 31, 2016, faculty from eight US medical schools were asked to write reflectively on two open-ended questions regarding institutional-level motivators and impediments to humanistic practice and teaching within their organizations. PARTICIPANTS: Sixty eight of the 92 (74%) study participants who received the survey provided written responses. All subjects who were sent the survey had participated in a year-long small-group faculty development program to enhance humanistic practice and teaching. As humanistic leaders, subjects should have insights into motivating and inhibiting factors. APPROACH: Participants' responses were analyzed using the constant comparative method. KEY RESULTS: Motivators included an organizational culture that enhances humanism, which we judged to be the overarching theme. Related themes included leadership supportive of humanistic practice, responsibility to role model humanism, organized activities that promote humanism, and practice structures that facilitate humanism. Impediments included top down organizational culture that inhibits humanism, along with related themes of non-supportive leadership, time and bureaucratic pressures, and non-facilitative practice structures. CONCLUSIONS: While healthcare has evolved rapidly, efforts to counteract the negative effects of changes in organizational and practice environments have largely focused on cultivating humanistic attributes in individuals. Our findings suggest that change at the organizational level is at least equally important. Physicians in our study described the characteristics of an organizational culture that supports and embraces humanism. We offer suggestions for organizational change that keep humanistic and compassionate patient care as its central focus.


Assuntos
Atenção à Saúde/organização & administração , Docentes de Medicina/organização & administração , Humanismo , Cultura Organizacional , Médicos/organização & administração , Ensino/organização & administração , Adulto , Esgotamento Profissional/prevenção & controle , Atenção à Saúde/tendências , Docentes de Medicina/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Médicos/tendências , Inquéritos e Questionários , Ensino/tendências
7.
Molecules ; 24(1)2018 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-30597941

RESUMO

The seeds of cultivated peanut, Arachis hypogaea, are an agronomically important crop produced for human nutrition, oilseed and feed stock. Peanut seed is the single most expensive variable input cost and thus producers require seed with excellent performance in terms of germination efficiency. During the maturation process, triglycerides are stored in oil bodies as an energy resource during germination and seedling development. The stability of oil body membranes is essential for nutrient mobilization during germination. This study focused on evaluating the phytosterol composition in seed components including the kernel, embryo (heart), and seed coat or skin. Samples of different maturity classes were analyzed for macronutrient and phytosterol content. The three biosynthetic end products in the phytosterol pathway, ß-sitosterol, campesterol and stigmasterol, comprised 82.29%, 86.39% and 94.25% of seed hearts, kernels and seed coats, respectively. Stigmasterol concentration was highest in the seed kernel, providing an excellent source of this sterol known to have beneficial effects on human health. Peanut hearts contained the highest concentration of sterols by mass, potentially providing protection and resources for the developing seedling. The amount of α-tocopherol increases in peanut hearts during the maturation process, providing protection from temperature stress, as well as stability required for seedling vigor. These results suggest that phytosterols may play a significant role in the performance of seeds, and provide a possible explanation for the poor germination efficiency of immature seeds.


Assuntos
Arachis/química , Compostos Fitoquímicos/química , Fitosteróis/química , Sementes/química , Arachis/crescimento & desenvolvimento , Micronutrientes/análise , Micronutrientes/química , Estrutura Molecular , Especificidade de Órgãos , Compostos Fitoquímicos/análise , Fitosteróis/análise , Terpenos/análise , Terpenos/química
8.
Plant Dis ; 101(11): 1843-1850, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30677310

RESUMO

Peanut (Arachis hypogaea) cultivars with resistance or tolerance to Cercospora arachidicola and/or Cercosporidium personatum, the causes of early and late leaf spot, respectively, are needed for organic production in the southeastern U.S. To determine the potential of new breeding lines for use in such production systems, field experiments were conducted in Tifton, GA, in 2014 and 2015 in which nine breeding lines and two cultivars, Georgia-06G and Georgia-12Y, were grown without foliar fungicide applications. In one set of trials, cultivar Georgia-12Y and most of the breeding lines evaluated had early season vigor ratings, early-season canopy width measurements, final plant populations, and pod yield that were greater than those of standard cultivar Georgia-06G. In those trials, final late leaf spot Florida scale ratings were lower and canopy reflectance measured as the normalized difference vegetation index (NDVI), was higher all the breeding lines than those of Georgia-06G. In another set of trials, two of those same breeding lines had final late leaf spot ratings similar to those of Georgia-12Y in 2014, whereas in 2015, six of those breeding lines had final leaf spot ratings that were lower than those of Georgia-12Y. Yields were similar for Georgia-12Y and all the breeding lines in the Gibbs Farm trials. Across years and breeding lines at the Lang Farm, the relationship between visual estimates of defoliation and NDVI was described by a two sector piecewise regression with NDVI decreasing more rapidly with increasing defoliation above approximately 89%. The utility of NDVI for spot comparisons among breeding lines appears to be limited to situations where there are differences in defoliation. Georgia-12Y and multiple breeding lines evaluated show potential for use in situations such as organic production where acceptable fungicides available for seed treatment and leaf spot control are limited.


Assuntos
Arachis , Melhoramento Vegetal , Doenças das Plantas , Arachis/microbiologia , Fungicidas Industriais , Doenças das Plantas/genética
9.
Mol Phylogenet Evol ; 100: 409-423, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27118179

RESUMO

African snake-eyed skinks are relatively small lizards of the genera Panaspis and Afroablepharus. Species allocation of these genera frequently changed during the 20th century based on morphology, ecology, and biogeography. Members of these genera occur primarily in savanna habitats throughout sub-Saharan Africa and include species whose highly conserved morphology poses challenges for taxonomic studies. We sequenced two mitochondrial (16S and cyt b) and two nuclear genes (PDC and RAG1) from 76 Panaspis and Afroablepharus samples from across eastern, central, and southern Africa. Concatenated gene-tree and divergence-dating analyses were conducted to infer phylogenies and biogeographic patterns. Molecular data sets revealed several cryptic lineages, with most radiations occurring during the mid-Miocene to Pliocene. We infer that rifting processes (including the formation of the East African Rift System) and climatic oscillations contributed to the expansion and contraction of savannas, and caused cladogenesis in snake-eyed skinks. Species in Panaspis and Afroablepharus used in this study, including type species for both genera, formed a monophyletic group. As a result, the latter genus should be synonymized with the former, which has priority. Conservatively, we continue to include the West African species P. breviceps and P. togoensis within an expanded Panaspis, but note that they occur in relatively divergent clades, and their taxonomic status may change with improved taxon sampling. Divergence estimates and cryptic speciation patterns of snake-eyed skinks were consistent with previous studies of other savanna vertebrate lineages from the same areas examined in this study.


Assuntos
Lagartos/genética , África Subsaariana , África Austral , Animais , Anuros/genética , Sequência de Bases , DNA Mitocondrial/genética , Evolução Molecular , Especiação Genética , Pradaria , Lagartos/classificação , Tipagem de Sequências Multilocus , Filogenia , Proteínas de Répteis/genética
10.
Med Educ ; 49(11): 1117-23, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26494064

RESUMO

OBJECTIVES: This study was designed to investigate the roles, characteristics and contributions to the educational process of highly influential teachers described retrospectively by faculty members who were former medical students and trainees. METHODS: The authors collected 20 appreciative inquiry narratives from a convenience sample of 22 faculty members (91% collection rate) at three medical schools that had volunteered to participate in a year-long programme of faculty development in humanism in medicine. The faculty members wrote narratives in response to the prompt: 'Write about your most influential teacher.' The four authors performed qualitative analysis of the 20 narratives using the constant comparison method to identify the characteristics of influential teachers. RESULTS: Particular relational features with their learners explain the profound influences of these teachers on the professional development of their learners. All influential teachers shared qualities of excellence in teaching and nearly all were described as caring, generous and selfless in their relationships with learners. CONCLUSIONS: Highly influential teachers have no official roles, yet appear to profoundly influence the professional development of many learners at various stages of the educational process.


Assuntos
Educação de Graduação em Medicina , Docentes de Medicina , Ensino , Docentes de Medicina/normas , Teoria Fundamentada , Humanismo , Humanos , Liderança , Mentores/psicologia , Narração , Estudantes de Medicina , Redação
11.
J Gen Intern Med ; 29(9): 1250-5, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24947051

RESUMO

BACKGROUND: There is increased emphasis on practicing humanism in medicine but explicit methods for faculty development in humanism are rare. OBJECTIVE: We sought to demonstrate improved faculty teaching and role modeling of humanistic and professional values by participants in a multi-institutional faculty development program as rated by their learners in clinical settings compared to contemporaneous controls. DESIGN: Blinded learners in clinical settings rated their clinical teachers, either participants or controls, on the previously validated 10-item Humanistic Teaching Practices Effectiveness (HTPE) questionnaire. PARTICIPANTS: Groups of 7-9 participants at 8 academic medical centers completed an 18-month faculty development program. Participating faculty were chosen by program facilitators at each institution on the basis of being promising teachers, willing to participate in the longitudinal faculty development program. INTERVENTION: Our 18-month curriculum combined experiential learning of teaching skills with critical reflection using appreciative inquiry narratives about their experiences as teachers and other reflective discussions. MAIN MEASURES: The main outcome was the aggregate score of the ten items on the questionnaire at all institutions. KEY RESULTS: The aggregate score favored participants over controls (P = 0.019) independently of gender, experience on faculty, specialty area, and/or overall teaching skills. CONCLUSIONS: Longitudinal, intensive faculty development that employs experiential learning and critical reflection likely enhances humanistic teaching and role modeling. Almost all participants completed the program. Results are generalizable to other schools.


Assuntos
Comportamento Cooperativo , Educação Médica/tendências , Docentes de Medicina , Humanismo , Papel (figurativo) , Desenvolvimento de Pessoal/tendências , Estudos de Coortes , Educação Médica/normas , Docentes de Medicina/normas , Feminino , Humanos , Estudos Longitudinais , Masculino , Estudos Prospectivos
12.
Med Educ ; 48(1): 67-74, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24330119

RESUMO

OBJECTIVES: This paper aims to honour the Hippocratic Oath in modern practice by providing reflections on the development of ways for doctors to know the whole person that have accrued over the five decades to the present. METHODS: I present a perspective piece, which includes personal reflections and cites relevant literature. RESULTS: Powerful role models sustained the concept of knowing the whole patient in an era of scientific medicine. Beginning in the 1980s, skills allowing ordinary doctors to know the whole patient were made transparent to learners in courses and medical school curricula. As we approach the 2020s, increasing numbers of doctors have mastered these skills and are teaching them. CONCLUSIONS: A modern way of practice is emerging; this emphasises the human side of medicine and its rewards, despite barriers such as those imposed by time limitations.


Assuntos
Educação Médica/métodos , Juramento Hipocrático , Saúde Holística/educação , Relações Médico-Paciente , Saúde Holística/ética , Humanismo , Humanos , Prática Profissional , Ensino/métodos
13.
Zootaxa ; (3814): 1-36, 2014 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-24943411

RESUMO

The taxonomic status of recently discovered populations of pygmy chameleons (Rhampholeon) from the northern Mozambique montane isolates of Mt. Chiperone, Mt. Mabu, Mt. Inago and Mt. Namuli are assessed, and compared with the closest geographical congeners, including Rhampholeon platyceps Günther 1893 from Mt. Mulanje, and Rh. chapmanorum Tilbury 1992 from the Malawi Hills, both in southern Malawi. Relationships were examined using morphological features and a phylogenetic analysis incorporating two mitochondrial and one nuclear marker. The phylogeny showed that each montane isolate contained a distinct, well-supported clade of chameleons. Chameleons from the Mozambican montane isolates are within a monophyletic clade inclusive of species from southern Malawi (Rh. platyceps and Rh. chapmanorum). Although some relationships are unresolved, the southern Malawi and Mozambican isolates appear to share their most recent common ancestor with species from the Eastern Arc Mountains and Southern Highlands of Tanzania and Malawi (Rh. moyeri, Rh. uluguruesis, Rh. nchisiensis). Along with Rh. beraduccii and Rh. acuminatus, all are included in the subgenus Rhinodigitum. Sister to this larger clade are species from west/central Africa (Rh. temporalis, Rh. spectrum) and the Rh. marshalli-gorongosae complex from southwest Mozambique and adjacent Zimbabwe. Morphological and molecular results confirm that Brookesia platyceps carri Loveridge 1953 is a junior subjective synonym of Rhampholeon platyceps Günther 1892. Historical records of Rh. platyceps from the Shire Highlands (Chiromo) and the Zomba Plateau, are incorrect and the species is now considered endemic to the Mulanje massif. All of the four newly discovered, isolated populations are genetically and morphologically distinct, and we take the opportunity to describe each as a new species. Rhampholeon (Rhinodigitum) maspictus sp. nov. is restricted to Mt. Mabu and distinguished by its large size, well-developed dorsal crenulations, and bright male breeding coloration; Rhampholeon (Rhinodigitum) nebulauctor sp. nov. is restricted to Mt. Chiperone and distinguished by its small size, weakly-developed dorsal crenulations, and a large rostral process in males; Rhampholeon (Rhinodigitum) tilburyi sp. nov. is restricted to Mt. Namuli and distinguished by its small size, weakly-developed dorsal crenulations, and prominent flexure of the snout in males; and Rhampholeon (Rhinodigitum) bruessoworum sp. nov. is restricted to Mt. Inago and distinguished by its small size, weakly-developed dorsal crenulations, large rostral process in males, and relatively long tail in both sexes. 


Assuntos
Lagartos/anatomia & histologia , Lagartos/classificação , Distribuição Animal , Animais , Tamanho Corporal , DNA Mitocondrial/genética , Ecossistema , Feminino , Ilhas , Lagartos/genética , Lagartos/crescimento & desenvolvimento , Masculino , Moçambique , Filogenia
14.
Zootaxa ; 3795: 501-22, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24870495

RESUMO

Recent research has shown that the helmeted terrapin (Pelomedusa subrufa), a species that occurs throughout sub-Saharan Africa, in Madagascar and the southwestern Arabian Peninsula, consists of several deeply divergent genetic lineages. Here we examine all nominal taxa currently synonymized with Pelomedusa subrufa (Bonnaterre, 1789) and provide mitochondrial DNA sequences of type specimens or topotypic material for most taxa. Lectotypes are designated for Testudo galeata Schoepff, 1792, Pentonyx capensis Duméril & Bibron, 1835, Pelomedusa nigra Gray, 1863, Pelomedusa galeata var. disjuncta Vaillant & Grandidier, 1910, and Pelomedusa galeata damarensis Hewitt, 1935. For Pelomedusa gasconi Rochebrune, 1884, a taxon without preserved type material, a neotype is designated. Type material of Pentonix americana Cornalia, 1849, a nominal species without credible type locality, is lost and its identity remains questionable. Also the holotype of Pelomedusa galeata orangensis Hewitt, 1935 is lost, but its allocation to the only genetic lineage occurring in South Africa is unambiguous. Phylogenetic analyses of type sequences or topotypic material reveal that the remaining nominal taxa represent three of the nine previously identified lineages of Pelomedusa. Among these three lineages is the South African one. Type specimens of Pentonyx gehafie Rüppell, 1835 correspond to an additional distinct lineage. The present study provides a sound basis for a subsequent integrative taxonomic revision of the Pelomedusa complex.


Assuntos
Biodiversidade , Tartarugas/classificação , África Subsaariana , Animais , Feminino , Madagáscar , Masculino , Oriente Médio , Filogenia , Análise de Sequência de DNA , Tartarugas/anatomia & histologia , Tartarugas/genética
15.
Zootaxa ; 3795: 523-48, 2014 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-24870496

RESUMO

Using nearly range-wide sampling, we analyze up to 1848 bp of mitochondrial DNA of 183             helmeted terrapins and identify a minimum of 12 deeply divergent species-level clades. Uncorrected p distances of these clades equal or clearly exceed those between the currently recognized species of Pelusios, the genus most closely related to Pelomedusa. We correlate genetic discontinuities of Pelomedusa with data on morphology and endoparasites and describe six new Pelomedusa species. Moreover, we restrict the name Pelomedusa subrufa (Bonnaterre, 1789) to one genetic lineage and resurrect three further species from its synonymy, namely P. galeata (Schoepff, 1792), P. gehafie (Rüppell, 1835), and P. olivacea (Schweigger, 1812). In addition to these ten Pelomedusa species, we identify two further clades from Cameroon and Sudan with similar levels of genetic divergence that remain unnamed candidate species. We also note that some problematical terrapins from South Africa and Somalia may represent two additional candidate species. Some of the Pelomedusa species are morphologically distinctive, whilst others can only be identified by molecular markers and are therefore morphologically cryptic taxa.


Assuntos
Biodiversidade , DNA Mitocondrial , Tartarugas/classificação , África Subsaariana , Animais , Feminino , Madagáscar , Masculino , Oriente Médio , Filogenia , Tartarugas/anatomia & histologia , Tartarugas/genética
16.
Plants (Basel) ; 13(8)2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38674520

RESUMO

Physiological maturity impacts seed quality through various mechanisms including vigor, desiccation tolerance, dormancy induction, synthesis of raw materials (including seed storage proteins), and the reorganization of metabolisms. Peanut seed development can be classified into seven classes with four incremental stages per class. Based on the mesocarp color, the final three stages are commonly referred to as "orange", "brown", and "black". In 2017, freshly harvested pods from one genotype of runner market-type peanuts grown under conventional practices were obtained from the University of Georgia research facility. The pods were removed from the plant material and 'pod blasted' to reveal the mesocarp. After separation, the remainder of the pod outer layer was removed, and the seeds were segregated for proteomic analysis. The raw peanuts were analyzed by bottom-up LC-MS/MS proteomics, which was conducted by the Proteomics Resource Center at the Rockefeller University, to identify the significant protein composition differences in each maturity class. The proteomic data revealed differentially expressed proteins as a function of maturity class with multiple functions including plant defense, metabolism, cell signaling, nutrient accumulation, and packaging. Understanding the processes needed for seed maturation will enable peanut scientists to evaluate the traits needed for robust germination, hardiness of the seed in response to disease, and nutrient quality.

17.
Sci Rep ; 14(1): 5971, 2024 03 12.
Artigo em Inglês | MEDLINE | ID: mdl-38472297

RESUMO

Recent biological surveys of ancient inselbergs in southern Malawi and northern Mozambique have led to the discovery and description of many species new to science, and overlapping centres of endemism across multiple taxa. Combining these endemic taxa with data on geology and climate, we propose the 'South East Africa Montane Archipelago' (SEAMA) as a distinct ecoregion of global biological importance. The ecoregion encompasses 30 granitic inselbergs reaching > 1000 m above sea level, hosting the largest (Mt Mabu) and smallest (Mt Lico) mid-elevation rainforests in southern Africa, as well as biologically unique montane grasslands. Endemic taxa include 127 plants, 45 vertebrates (amphibians, reptiles, birds, mammals) and 45 invertebrate species (butterflies, freshwater crabs), and two endemic genera of plants and reptiles. Existing dated phylogenies of endemic animal lineages suggests this endemism arose from divergence events coinciding with repeated isolation of these mountains from the pan-African forests, together with the mountains' great age and relative climatic stability. Since 2000, the SEAMA has lost 18% of its primary humid forest cover (up to 43% in some sites)-one of the highest deforestation rates in Africa. Urgently rectifying this situation, while addressing the resource needs of local communities, is a global priority for biodiversity conservation.


Assuntos
Borboletas , Animais , Biodiversidade , África Oriental , Répteis , Florestas , África do Sul , Filogenia , Mamíferos
18.
Zootaxa ; 3635: 201-23, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26097943

RESUMO

Phylogenetic reconstruction using the mitochondrial 16S marker shows that geographically separated populations of the poorly known Hyperolius cinereus (Anura: Hyperoliidae) from Angola form two distinct clades. The description of H. cinereus was originally based on only a single preserved adult male. Fresh material of both sexes allowed a detailed redescription of the species, which is restricted mainly to the south-draining Cunene and Cubango river systems. Bioacoustic and morphological characters, in conjunction with colouration differences, allow the description of a cryptic sister species from Lagoa Carumbo in north-eastern Angola, occurring in the Luele and Lovuo river systems of the Congo drainage basin. Tadpoles, for H. cinereus and the new species, are described.


Assuntos
Ranidae/anatomia & histologia , Ranidae/classificação , Angola , Distribuição Animal , Animais , Ecossistema , Feminino , Larva , Masculino , Filogenia , Ranidae/genética , Ranidae/fisiologia , Rios , Especificidade da Espécie , Vocalização Animal
19.
Zootaxa ; 3710: 415-35, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26106703

RESUMO

A new species of high elevation dwarf gecko (Gekkonidae: Lygodactylus) is described from Mount Namuli, northern Mozambique. This new species is distinguished from other closely related species in the genus Lygodactylus by body size, scalation, and color, and is genetically divergent from congeners. The species is most similar genetically and morphologically to Lygodactylus rex, the King Dwarf Gecko, which is endemic to Mount Mulanje, Malawi. Mount Mulanje and Mount Namuli are two of several understudied inselbergs forming the southern limit of the Afromontane archipelago in Malawi and Mozambique. The sister taxon relationship of the dwarf gecko species on Mount Mulanje and Mount Namuli illustrates the historical biogeographic connections between these inselbergs, a pattern which is emerging with continued work in this region. The discovery of this new species adds to a growing list of species unique to Mount Namuli, and further establishes this montane region as a conservation priority.


Assuntos
Lagartos/classificação , Animais , Ecossistema , Feminino , Lagartos/anatomia & histologia , Lagartos/genética , Masculino , Moçambique , Filogenia , Pigmentação
20.
Zootaxa ; 3669: 101-14, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-26312325

RESUMO

Molecular phylogenetic analyses of southern African lacertid lizards (Eremiadini) using mitochondrial and nuclear markers revealed two examples of generic assignments incompatible with monophyletic clades. Australolacerta Arnold 1989, a genus endemic to South Africa and to which two isolated species have been referred, is paraphyletic at the generic level. In addition, the species Ichnotropis squamulosa Peters 1854 was found to be embedded within the genus Meroles. To resolve the paraphyly in Australolacerta we erect a new genus, Vhembelacerta Edwards, Branch, Herrel, Vanhooydonck, Measey, & Tolley, gen. nov., to accommodate Lacerta rupicola FitzSimons 1933. To maintain a monophyletic Ichnotropis Peters 1854, Ichnotropis squamulosa Peters 1854 is transferred to Meroles Gray 1838, now named Meroles squamulosus comb. nov. Where necessary the genera affected by these actions are re-characterized.


Assuntos
Distribuição Animal , Lagartos/classificação , Lagartos/genética , Filogenia , Animais , Lagartos/fisiologia , África do Sul , Especificidade da Espécie
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