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1.
Mol Phylogenet Evol ; 194: 108022, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38325534

RESUMO

The world's largest butterfly genus Delias, commonly known as Jezebels, comprises ca. 251 species found throughout Asia, Australia, and Melanesia. Most species are endemic to islands in the Indo-Australian Archipelago or to New Guinea and nearby islands in Melanesia, and many species are restricted to montane habitats over 1200 m. We inferred an extensively sampled and well-supported molecular phylogeny of the group to better understand the spatial and temporal dimensions of its diversification. The remarkable diversity of Delias evolved in just ca. 15-16 Myr (crown age). The most recent common ancestor of a clade with most of the species dispersed out of New Guinea ca. 14 Mya, but at least six subsequently diverging lineages dispersed back to the island. Diversification was associated with frequent dispersal of lineages among the islands of the Indo-Australian Archipelago, and the divergence of sister taxa on a single landmass was rare and occurred only on the largest islands, most notably on New Guinea. We conclude that frequent inter-island dispersal during the Neogene-likely facilitated by frequent sea level change-sparked much diversification during that period. Many extant New Guinea lineages started diversifying 5 Mya, suggesting that orogeny facilitated their diversification. Our results largely agree with the most recently proposed species group classification system, and we use our large taxon sample to extend this system to all described species. Finally, we summarize recent insights to speculate how wing pattern evolution, mimicry, and sexual selection might also contribute to these butterflies' rapid speciation and diversification.


Assuntos
Borboletas , Animais , Filogenia , Borboletas/genética , Nova Guiné , Austrália , Ecossistema
2.
Nat Ecol Evol ; 7(11): 1834-1843, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37679456

RESUMO

Virus transmission between host species underpins disease emergence. Both host phylogenetic relatedness and aspects of their ecology, such as species interactions and predator-prey relationships, may govern rates and patterns of cross-species virus transmission and hence zoonotic risk. To address the impact of host phylogeny and ecology on virus diversity and evolution, we characterized the virome structure of a relatively isolated island ecological community in Fiordland, New Zealand, that are linked through a food web. We show that phylogenetic barriers that inhibited cross-species virus transmission occurred at the level of host phyla (between the Chordata, Arthropoda and Streptophyta) as well as at lower taxonomic levels. By contrast, host ecology, manifest as predator-prey interactions and diet, had a smaller influence on virome composition, especially at higher taxonomic levels. The virus-host community comprised a 'small world' network, in which hosts with a high diversity of viruses were more likely to acquire new viruses, and generalist viruses that infect multiple hosts were more likely to infect additional species compared to host specialist viruses. Such a highly connected ecological community increases the likelihood of cross-species virus transmission, particularly among closely related species, and suggests that host generalist viruses present the greatest risk of disease emergence.


Assuntos
Ecologia , Ecossistema , Filogenia , Especificidade de Hospedeiro , Nova Zelândia
3.
J Wildl Dis ; 58(4): 836-846, 2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36136602

RESUMO

Coccidia infections in wild birds rarely cause clinical signs; however, disease and mortality can occur with predisposing environmental and host conditions. The Yellow-eyed Penguin (Megadyptes antipodes) is an endangered species endemic to New Zealand that has seen significant ongoing population decline. The aim of this study was to examine the host-pathogen dynamics of coccidian parasites in two wild populations of Yellow-eyed Penguin: the mainland (South Island) population and the sub-Antarctic (Enderby Island) population. There was weak evidence for a difference in the prevalence of the Eimeria sp. in birds from Enderby Island (76.6%; 36/47; 95% confidence interval [CI] 62.78-86.4%) and the South Island of New Zealand (58.54%; 24/41; 95% CI 43.37-72.24%). The mean pathogen load in penguins on Enderby Island was 9,723 oocysts/g of feces (SE=5831 oocysts/g) and from the South Island of New Zealand was 1,050 oocysts/g (SE=398 oocysts/g). No evidence of an association was found between pathogen load and body weight in either study population. The morphology of the sporulated coccidial oocysts was consistent with a novel species of Eimeria. There was statistically significant variation between the oocysts collected from the two sites in all measurements apart from the oocyst wall thickness. However, the standard technique of assessing linear regressions of the length and width of oocysts from both sampling sites was 0.80, and therefore above the standard R2>0.5 used to indicate variation within a single population of oocysts, suggesting that only a single species of Eimeria was present at both sampling locations. The prevalence and pathogen load of Eimeria sp. was substantially higher than previous reports of coccidial oocysts in Yellow-eyed Penguins and free-living Sphenisciformes globally. This host-parasite relationship deserves further investigation, as the impact of this novel organism on the population remains unclear.


Assuntos
Eimeria , Spheniscidae , Animais , Nova Zelândia/epidemiologia , Regiões Antárticas
4.
Water Res ; 220: 118719, 2022 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-35704979

RESUMO

This study assessed the feasibility of a novel vacuum-enhanced anaerobic digestion technology, referred to as IntensiCarbTM (IC), under mild vacuum pressure (110 mbar), compared to a control (conventional fermenter), and evaluated the impact of the vacuum on the activities of various microbial groups. Both fermenters (test and control) were operated with mixed (50% v/v) municipal sludge at solids concentrations of 2-2.5%, pH of 7.8-8.1, 40-45 °C, a theoretical solids retention time (SRT) of 3 days with different hydraulic retention times (HRT). The intensification factor (IF) of the IC, defined as SRT/HRT, was controlled at 1.3 and 2.0. Simultaneous thickening and fermentation intensification were achieved. Compared with the control, the IC, despite the shorter HRTs, achieved 29.5 to 90.2% increase in the VFA yield (79 to 116 mg ΔVFA/ g VSS vs 61 mg ΔVFA/ g VSS), and 16.2% to 56.4% increase (280 to 377 mg ΔsCOD/ g VSS vs 241 mg ΔsCOD/ g VSS), in the hydrolysis yield. Fermentate from the IC exhibited comparable specific denitrification rates to acetate. Further, the solids-free condensate contained low nutrient concentrations, and thus was far superior to a typical centrates from dewatering as a carbon source. No adverse effects of vacuum on the activity of fermentative bacteria and methanogens were observed. This study demonstrated that the IC can be deployed as an intensification technology for both fermentation and anaerobic digestion of biosolids with the additional significant advantage, i.e. elimination of sidestream ammonia treatment requirements.


Assuntos
Reatores Biológicos , Esgotos , Anaerobiose , Fermentação , Hidrólise , Esgotos/microbiologia , Vácuo
5.
Virus Evol ; 8(1): veac032, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35494173

RESUMO

Although water-borne viruses have important implications for the health of humans and other animals, little is known about the impact of human land use on viral diversity and evolution in water systems such as rivers. We used metatranscriptomic sequencing to compare the diversity and abundance of viruses at sampling sites along a single river in New Zealand that differed in human land-use impacts, ranging from pristine to urban. From this, we identified 504 putative virus species, of which 97 per cent were novel. Many of the novel viruses were highly divergent and likely included a new subfamily within the Parvoviridae. We identified at least sixty-three virus species that may infect vertebrates-most likely fish and water birds-from the Astroviridae, Birnaviridae, Parvoviridae, and Picornaviridae. No putative human viruses were detected. Importantly, we observed differences in the composition of viral communities at sites impacted by human land use (farming and urban) compared to native forest sites (pristine). At the viral species level, the urban sites had higher diversity (327 virus species) than the farming (n = 150) and pristine sites (n = 119), and more viruses were shared between the urban and farming sites (n = 76) than between the pristine and farming or urban sites (n = 24). The two farming sites had a lower viral abundance across all host types, while the pristine sites had a higher abundance of viruses associated with animals, plants, and fungi. We also identified viruses linked to agriculture and human impact at the river sampling sites in farming and urban areas that were not present at the native forest sites. Although based on a small sample size, our study suggests that human land use can impact viral communities in rivers, such that further work is needed to reduce the impact of intensive farming and urbanisation on water systems.

6.
Nat Commun ; 12(1): 5717, 2021 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-34588433

RESUMO

The global increase in species richness toward the tropics across continents and taxonomic groups, referred to as the latitudinal diversity gradient, stimulated the formulation of many hypotheses to explain the underlying mechanisms of this pattern. We evaluate several of these hypotheses to explain spatial diversity patterns in a butterfly family, the Nymphalidae, by assessing the contributions of speciation, extinction, and dispersal, and also the extent to which these processes differ among regions at the same latitude. We generate a time-calibrated phylogeny containing 2,866 nymphalid species (~45% of extant diversity). Neither speciation nor extinction rate variations consistently explain the latitudinal diversity gradient among regions because temporal diversification dynamics differ greatly across longitude. The Neotropical diversity results from low extinction rates, not high speciation rates, and biotic interchanges with other regions are rare. Southeast Asia is also characterized by a low speciation rate but, unlike the Neotropics, is the main source of dispersal events through time. Our results suggest that global climate change throughout the Cenozoic, combined with tropical niche conservatism, played a major role in generating the modern latitudinal diversity gradient of nymphalid butterflies.


Assuntos
Distribuição Animal , Biodiversidade , Borboletas/fisiologia , Clima Tropical , Animais , Extinção Biológica , Genes de Insetos , Especiação Genética , Geografia , Filogenia , Análise Espaço-Temporal
8.
Light Sci Appl ; 10(1): 114, 2021 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-34059619

RESUMO

Controlling coherent interaction between optical fields and quantum systems in scalable, integrated platforms is essential for quantum technologies. Miniaturised, warm alkali-vapour cells integrated with on-chip photonic devices represent an attractive system, in particular for delay or storage of a single-photon quantum state. Hollow-core fibres or planar waveguides are widely used to confine light over long distances enhancing light-matter interaction in atomic-vapour cells. However, they suffer from inefficient filling times, enhanced dephasing for atoms near the surfaces, and limited light-matter overlap. We report here on the observation of modified electromagnetically induced transparency for a non-diffractive beam of light in an on-chip, laterally-accessible hollow-core light cage. Atomic layer deposition of an alumina nanofilm onto the light-cage structure was utilised to precisely tune the high-transmission spectral region of the light-cage mode to the operation wavelength of the atomic transition, while additionally protecting the polymer against the corrosive alkali vapour. The experiments show strong, coherent light-matter coupling over lengths substantially exceeding the Rayleigh range. Additionally, the stable non-degrading performance and extreme versatility of the light cage provide an excellent basis for a manifold of quantum-storage and quantum-nonlinear applications, highlighting it as a compelling candidate for all-on-chip, integrable, low-cost, vapour-based photon delay.

9.
Opt Express ; 28(3): 3159-3170, 2020 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-32121989

RESUMO

We present an efficient and robust source of photons at the 87Rb D1-line (795 nm) with a narrow bandwidth of δ = 226(1) MHz. The source is based on non-degenerate, cavity-enhanced spontaneous parametric down-conversion in a monolithic optical parametric oscillator far below threshold. The setup allows for efficient coupling to single mode fibers. A heralding efficiency of ηheralded = 45(5) % is achieved, and the uncorrected number of detected photon pairs is 3.8 × 103/(s mW). For pair generation rates up to 5 × 105/s, the source emits heralded single photons with a normalized, heralded, second-order correlation function g c(2)<0.01. The source is intrinsically stable due to the monolithic configuration. Frequency drifts are on the order of δ/20 per hour without active feedback on the emission frequency. We achieved fine-tuning of the source frequency within a range of >2 GHz by applying mechanical strain.

10.
Pediatrics ; 143(6)2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31101703

RESUMO

BACKGROUND: Early HIV testing is needed for treatment success in young infants, but universal testing is expensive. In this study, we examined the feasibility of early infant HIV risk scores for targeted polymerase chain reaction (PCR) testing and early HIV diagnosis. METHODS: A cross-sectional cohort of newborns exposed to HIV was enrolled and PCR tested within 72 hours. We quantified associations between HIV infection and clinical and laboratory maternal-infant parameters by logistic regression models and determined sensitivity and specificity for derived risk scores. RESULTS: From August 2014 to December 2016, 1759 participants were enrolled. Mothers without antenatal care (5.7% [97 of 1688]) were more likely to deliver newborns who are PCR-positive (P = .0005). A total of 1 in 5 mothers (217 of 990; 21.9%) had HIV viral load (VL) >1000 copies per µL. A total of 432 of 1655 (26.1%) infants were preterm. Low birth weight was documented in 398 of 1598 (24.55%) and 13 of 31 (40.63%) newborns who are PCR-negative and -positive, respectively (P = .0329). A total of 204 of 1689 (12.08%) were growth restricted or small for gestational age, and 6 of 37 (16.22%) were PCR-positive. Symptomatic newborns frequently tested positive (P = .0042). The HIV PCR positivity rate was 2.2% (37 of 1703). Two-risk (combined 3-drug antiretroviral therapy [cART] duration, VL), 3-risk (cART duration, VL, symptomatic newborn), and 4-risk (cART duration, VL, symptomatic, small for gestational age newborn) models for HIV acquisition had predictive probability of 0.28, 0.498, and 0.57, respectively; this could guide targeted birth testing. However, using the 3- and 4-risk scores (probability 0.02 and 0.04), 20% and 24% will be missed compared with universal testing. CONCLUSIONS: Targeted newborn testing requires access to maternal VL. Even if risk models include parameters such as maternal cART history, birth weight, weeks' gestation, and symptoms, 1 in 5 newborns who are infected will not be targeted. At present, we support universal PCR testing at birth within the South African prevention of mother-to-child transmission of HIV context.


Assuntos
Infecções por HIV/diagnóstico , Infecções por HIV/genética , Transmissão Vertical de Doenças Infecciosas , Triagem Neonatal/métodos , Complicações Infecciosas na Gravidez/diagnóstico , Complicações Infecciosas na Gravidez/genética , Adulto , Estudos de Coortes , Estudos Transversais , Diagnóstico Precoce , Feminino , Infecções por HIV/epidemiologia , Humanos , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Reação em Cadeia da Polimerase em Tempo Real/métodos , Fatores de Risco , África do Sul/epidemiologia , Carga Viral/genética , Carga Viral/métodos
11.
Zookeys ; (774): 1-15, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30034260

RESUMO

The most distinctive species of Polyura, P. inopinatus, described from a single specimen said to be from North Sulawesi, Indonesia, has been a great mystery since it was first described by Röber, in 1940. The holotype, originally illustrated in monochrome in the journal Deutsche Entomologische Zeitschrift, Iris, was lost very soon after it was described, almost certainly destroyed during allied bombing of Dresden in the 1940s. No other specimen was known for almost eight decades. We suggest that the type locality (Sulawesi) is incorrect and that the holotype was more likely to have been collected in the Baining Mountains, East New Britain Province, Papua New Guinea. We report the recent discovery of several male P. inopinatus from West New Britain Province, and describe and illustrate specimens. A neotype is designated.

12.
Mol Phylogenet Evol ; 123: 50-58, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29428509

RESUMO

Hypolimnas butterflies (Nymphalidae), commonly known as eggflies, are a popular model system for studying a wide range of ecological questions including mimicry, polymorphism, wing pattern evolution, and Wolbachia-host interactions. The lack of a time-calibrated phylogeny for this group has precluded understanding its evolutionary history. We reconstruct a species-level phylogeny using a nine gene dataset and estimate species divergence times. Based on the resulting tree, we investigate the taxon's historical biogeography, examine the evolution of host plant preferences, and test the hypothesis that the endosymbiotic bacterium Wolbachia mediates gene transfer between species. Our analyses indicate that the species are grouped within three strongly supported, deeply divergent clades. However, relationships among these three clades are uncertain. In addition, many Hypolimnas species are not monophyletic or monophyletic with weak support, suggesting widespread incomplete lineage sorting and/or introgression. Biogeographic analysis strongly indicates that the genus diverged from its ancestor in Africa and subsequently dispersed to Asia; the strength of this result is not affected by topological uncertainties. While the larvae of African species feed almost exclusively on Urticaceae, larvae of species found further east often feed on several additional families. Interestingly, we found an identical mitochondrial haplotype in two Hypolimnas species, H. bolina and H. alimena, and a strong association between this mitotype and the Wolbachia strain wBol1a. Future investigations should explore the plausibility of Wolbachia-mediated introgression between species.


Assuntos
Evolução Biológica , Borboletas/genética , Borboletas/microbiologia , Wolbachia/fisiologia , África , Animais , Sequência de Bases , Teorema de Bayes , Biodiversidade , DNA Mitocondrial/genética , Haplótipos/genética , Larva/fisiologia , Funções Verossimilhança , Mitocôndrias/genética , Filogenia , Filogeografia , Análise de Sequência de DNA
13.
Zookeys ; (571): 113-31, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27110161

RESUMO

Jamides vasilia sp. n., from montane West New Britain Province, Papua New Guinea, is described and illustrated. The new species is strongly divergent from other known Jamides Hübner, 1819 in possessing a high antenna-forewing length ratio, long androconia on the hindwing upperside and a strongly convex forewing inner margin in the male. It is compared by external structures, male genitalia and mtDNA sequence data to putative related species in the cyta group of Jamides. Notes on various Jamides taxa from the Bismarck Archipelago are also provided, with Jamides pseudosias (Rothschild, 1915) and Jamides reverdini (Fruhstorfer, 1915) recorded from New Britain for the first time.

14.
Mol Phylogenet Evol ; 91: 194-209, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26021440

RESUMO

The charismatic tropical Polyura Nawab butterflies are distributed across twelve biodiversity hotspots in the Indomalayan/Australasian archipelago. In this study, we tested an array of species delimitation methods and compared the results to existing morphology-based taxonomy. We sequenced two mitochondrial and two nuclear gene fragments to reconstruct phylogenetic relationships within Polyura using both Bayesian inference and maximum likelihood. Based on this phylogenetic framework, we used the recently introduced bGMYC, BPP and PTP methods to investigate species boundaries. Based on our results, we describe two new species Polyura paulettae Toussaint sp. n. and Polyura smilesi Toussaint sp. n., propose one synonym, and five populations are raised to species status. Most of the newly recognized species are single-island endemics likely resulting from the recent highly complex geological history of the Indomalayan-Australasian archipelago. Surprisingly, we also find two newly recognized species in the Indomalayan region where additional biotic or abiotic factors have fostered speciation. Species delimitation methods were largely congruent and succeeded to cross-validate most extant morphological species. PTP and BPP seem to yield more consistent and robust estimations of species boundaries with respect to morphological characters while bGMYC delivered contrasting results depending on the different gene trees considered. Our findings demonstrate the efficiency of comparative approaches using molecular species delimitation methods on empirical data. They also pave the way for the investigation of less well-known groups to unveil patterns of species richness and catalogue Earth's concealed, therefore unappreciated diversity.


Assuntos
Borboletas/classificação , Animais , Teorema de Bayes , Biodiversidade , Borboletas/anatomia & histologia , Borboletas/genética , Filogenia , Análise de Sequência de DNA
15.
Front Psychol ; 6: 429, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25954218

RESUMO

In the present paper, we report the results of an empirical study on the effects of cognitive load on operatic singing. The main aim of the study was to investigate to what extent a working memory task affected the timing of operatic singers' performance. Thereby, we focused on singers' tendency to speed up, or slow down their performance of musical phrases and pauses. Twelve professional operatic singers were asked to perform an operatic aria three times; once without an additional working memory task, once with a concurrent working memory task (counting shapes on a computer screen), and once with a relatively more difficult working memory task (more shapes to be counted appearing one after another). The results show that, in general, singers speeded up their performance under heightened cognitive load. Interestingly, this effect was more pronounced in pauses-more in particular longer pauses-compared to musical phrases. We discuss the role of sensorimotor control and feedback processes in musical timing to explain these findings.

16.
Zootaxa ; 3926(1): 147-50, 2015 Mar 04.
Artigo em Inglês | MEDLINE | ID: mdl-25781776

RESUMO

For 30 years the highly distinctive Schneider's Surprise butterfly, Tiradelphe schneideri Ackery & Vane-Wright, 1984, has been known only from the two original type specimens, both female. Here we describe and illustrate the previously unknown male of this Guadalcanal endemic member of the Danaina-the subtribe of Nymphalidae: Danainae to which Tiradelphe has always been assigned. Unexpectedly, male T. schneideri completely lack alar androconia, and are thus  unlike all other species of Danaina and its sister group, the Amaurina. The new information will permit a reassessment of the phylogenetic relationships of Tiradelphe. This enigmatic genus may well be more isolated than previously supposed, with implications not only for our understanding of pheromone communication in these insects, but also the evolution and biogeography of the tribe Danaini in the Indo-Pacific.


Assuntos
Borboletas/classificação , Estruturas Animais/anatomia & histologia , Estruturas Animais/crescimento & desenvolvimento , Animais , Evolução Biológica , Tamanho Corporal , Borboletas/anatomia & histologia , Borboletas/crescimento & desenvolvimento , Ecossistema , Feminino , Masculino , Tamanho do Órgão , Especificidade da Espécie
17.
PLoS One ; 9(12): e114234, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25489742

RESUMO

In this study we explore how music can entrain human walkers to synchronise to the musical beat without being instructed to do so. For this, we use an interactive music player, called D-Jogger, that senses the user's walking tempo and phase. D-Jogger aligns the music by manipulating the timing difference between beats and footfalls. Experiments are reported that led to the development and optimisation of four alignment strategies. The first strategy matched the music's tempo continuously to the runner's pace. The second strategy matched the music's tempo at the beginning of a song to the runner's pace, keeping the tempo constant for the remainder of the song. The third alignment starts a song in perfect phase synchrony and continues to adjust the tempo to match the runner's pace. The fourth and last strategy additionally adjusts the phase of the music so each beat matches a footfall. The first two strategies resulted in a minor increase of steps in phase synchrony with the main beat when compared to a random playlist, the last two strategies resulted in a strong increase in synchronised steps. These results may be explained in terms of phase-error correction mechanisms and motor prediction schemes. Finding the phase-lock is difficult due to fluctuations in the interaction, whereas strategies that automatically align the phase between movement and music solve the problem of finding the phase-locking. Moreover, the data show that once the phase-lock is found, alignment can be easily maintained, suggesting that less entrainment effort is needed to keep the phase-lock, than to find the phase-lock. The different alignment strategies of D-Jogger can be applied in different domains such as sports, physical rehabilitation and assistive technologies for movement performance.


Assuntos
Música , Tecnologia/métodos , Caminhada , Estimulação Acústica , Algoritmos , Equipamentos e Provisões Elétricas , Feminino , Pé/fisiologia , Humanos , Masculino , Tecnologia/instrumentação , Tecnologia sem Fio , Adulto Jovem
18.
Zookeys ; (395): 33-55, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24715788

RESUMO

Six new species of the large lycaenid genus Philiris Röber, 1891 (Philiris petriei sp. n., Philiris bubalisatina sp. n., Philiris baiteta sp. n., Philiris radicala sp. n., Philiris hindenburgensis sp. n. and Philiris parsonsi sp. n.), from Papua New Guinea, are described and illustrated, as are the early stages of the former taxon, with Litsea sp. near callophyllantha K. Schum (Lauraceae) recorded as the larval food plant. The holotypes of all but the latter are deposited in the ANIC, with that of P. parsonsi located in the BMNH. The external facies and male genitalia of all new species are compared in detail to putative known related species, and the types of these, in nearly all cases, are also illustrated.

19.
BMC Evol Biol ; 10: 172, 2010 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-20537168

RESUMO

BACKGROUND: Butterflies of the subtribe Mycalesina (Nymphalidae: Satyrinae) are important model organisms in ecology and evolution. This group has radiated spectacularly in the Old World tropics and presents an exciting opportunity to better understand processes of invertebrate rapid radiations. However, the generic-level taxonomy of the subtribe has been in a constant state of flux, and relationships among genera are unknown. There are six currently recognized genera in the group. Mycalesis, Lohora and Nirvanopsis are found in the Oriental region, the first of which is the most speciose genus among mycalesines, and extends into the Australasian region. Hallelesis and Bicyclus are found in mainland Africa, while Heteropsis is primarily Madagascan, with a few species in Africa. We infer the phylogeny of the group with data from three genes (total of 3139 bp) and use these data to reconstruct events in the biogeographic history of the group. RESULTS: The results indicate that the group Mycalesina radiated rapidly around the Oligocene-Miocene boundary. Basal relationships are unresolved, but we recover six well-supported clades. Some species of Mycalesis are nested within a primarily Madagascan clade of Heteropsis, while Nirvanopsis is nested within Lohora. The phylogeny suggests that the group had its origin either in Asia or Africa, and diversified through dispersals between the two regions, during the late Oligocene and early Miocene. The current dataset tentatively suggests that the Madagascan fauna comprises two independent radiations. The Australasian radiation shares a common ancestor derived from Asia. We discuss factors that are likely to have played a key role in the diversification of the group. CONCLUSIONS: We propose a significantly revised classification scheme for Mycalesina. We conclude that the group originated and radiated from an ancestor that was found either in Asia or Africa, with dispersals between the two regions and to Australasia. Our phylogeny paves the way for further comparative studies on this group that will help us understand the processes underlying diversification in rapid radiations of invertebrates.


Assuntos
Borboletas/classificação , Evolução Molecular , Especiação Genética , Filogenia , África , Animais , Australásia , Teorema de Bayes , Borboletas/genética , Genes de Insetos , Geografia , Funções Verossimilhança , Madagáscar , Análise de Sequência de DNA
20.
Mol Phylogenet Evol ; 54(2): 386-94, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19686856

RESUMO

We report a rapid radiation of a group of butterflies within the family Nymphalidae and examine some aspects of popular analytical methods in dealing with rapid radiations. We attempted to infer the phylogeny of butterflies belonging to the subtribe Coenonymphina sensu lato using five genes (4398bp) with Maximum Parsimony, Maximum Likelihood and Bayesian analyses. Initial analyses suggested that the group has undergone rapid speciation within Australasia. We further analyzed the dataset with different outgroup combinations the choice of which had a profound effect on relationships within the ingroup. Modelling methods recovered Coenonymphina as a monophyletic group to the exclusion of Zipaetis and Orsotriaena, irrespective of outgroup combination. Maximum Parsimony occasionally returned a polyphyletic Coenonymphina, with Argyronympha grouping with outgroups, but this was strongly dependent on the outgroups used. We analyzed the ingroup without any outgroups and found that the relationships inferred among taxa were different from those inferred when either of the outgroup combinations was used, and this was true for all methods. We also tested whether a hard polytomy is a better hypothesis to explain our dataset, but could not find conclusive evidence. We therefore conclude that the major lineages within Coenonymphina form a near-hard polytomy with regard to each other. The study highlights the importance of testing different outgroups rather than using results from a single outgroup combination of a few taxa, particularly in difficult cases where basal nodes appear to receive low support. We provide a revised classification of Coenonymphina; Zipaetis and Orsotriaena are transferred to the tribe Eritina.


Assuntos
Borboletas/genética , Evolução Molecular , Especiação Genética , Filogenia , Animais , Australásia , Teorema de Bayes , Borboletas/classificação , Genes de Insetos , Funções Verossimilhança , Modelos Genéticos , Análise de Sequência de DNA
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