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1.
Neotrop Entomol ; 43(3): 218-26, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27193617

RESUMO

The nymphalid Paulogramma hydarnis (Godart) (n. comb., previously in the genus Callicore) is an endangered butterfly present in a few montane sites in the Atlantic Forest in the Southeastern Brazil. The precise systematic position of P. hydarnis was previously unknown. Based on molecular data, we find that it is sister to Paulogramma pygas (Godart) (n. comb., also previously in Callicore), a common and widespread species in the Neotropics. In addition, we find that Callicore is not monophyletic and that "Callicore" hydarnis (along with other species) is more related to the genus Paulogramma, and should thus be placed in that genus. The genus Paulogramma is now composed by the following species: Paulogramma pyracmon (Godart), Paulogramma eunomia (Hewitson) n. comb., Paulogramma hydarnis (Godart) n. comb., Paulogramma hystaspes (Fabricius) n. comb., Paulogramma pygas (Godart) n. comb., and Paulogramma tolima (Hewitson, 1852) n. comb. Museum specimens and field data report P. hydarnis in four sites in Southeastern Brazil. Recently, P. hydarnis was recorded for the first time at Parque Nacional do Caparaó, states of Espírito Santo and Minas Gerais, expanding its distribution about 200 km northward of the previously known limit. Although regularly recorded in some sites, most records are historic, before the 1960s, and the current conservation situation of this species is delicate, deserving attention.


Assuntos
Borboletas , Espécies em Perigo de Extinção , Distribuição Animal , Animais , Brassicaceae , Brasil
2.
Science ; 342(6160): 871-4, 2013 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-24233726

RESUMO

The geographic and temporal origins of the domestic dog remain controversial, as genetic data suggest a domestication process in East Asia beginning 15,000 years ago, whereas the oldest doglike fossils are found in Europe and Siberia and date to >30,000 years ago. We analyzed the mitochondrial genomes of 18 prehistoric canids from Eurasia and the New World, along with a comprehensive panel of modern dogs and wolves. The mitochondrial genomes of all modern dogs are phylogenetically most closely related to either ancient or modern canids of Europe. Molecular dating suggests an onset of domestication there 18,800 to 32,100 years ago. These findings imply that domestic dogs are the culmination of a process that initiated with European hunter-gatherers and the canids with whom they interacted.


Assuntos
Animais Domésticos/genética , Cães/genética , Genoma Mitocondrial/genética , Animais , Sequência de Bases , Cruzamento , Europa (Continente) , Dados de Sequência Molecular , Filogenia , Lobos/genética
3.
J Evol Biol ; 26(10): 2095-106, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23909947

RESUMO

Molecular studies of natural populations are often designed to detect and categorize hidden layers of cryptic diversity, and an emerging pattern suggests that cryptic species are more common and more widely distributed than previously thought. However, these studies are often decoupled from ecological and behavioural studies of species divergence. Thus, the mechanisms by which the cryptic diversity is distributed and maintained across large spatial scales are often unknown. In 1988, it was discovered that the common Eurasian Wood White butterfly consisted of two species (Leptidea sinapis and Leptidea reali), and the pair became an emerging model for the study of speciation and chromosomal evolution. In 2011, the existence of a third cryptic species (Leptidea juvernica) was proposed. This unexpected discovery raises questions about the mechanisms preventing gene flow and about the potential existence of additional species hidden in the complex. Here, we compare patterns of genetic divergence across western Eurasia in an extensive data set of mitochondrial and nuclear DNA sequences with behavioural data on inter- and intraspecific reproductive isolation in courtship experiments. We show that three species exist in accordance with both the phylogenetic and biological species concepts and that additional hidden diversity is unlikely to occur in Europe. The Leptidea species are now the best studied cryptic complex of butterflies in Europe and a promising model system for understanding the formation of cryptic species and the roles of local processes, colonization patterns and heterospecific interactions for ecological and evolutionary divergence.


Assuntos
Borboletas/genética , Variação Genética , Isolamento Reprodutivo , Animais , Borboletas/fisiologia , DNA/química , DNA Mitocondrial/química , Fluxo Gênico , Marcadores Genéticos , Geografia , Filogenia , Análise de Sequência de DNA , Comportamento Sexual Animal
4.
J Evol Biol ; 26(6): 1244-53, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23675756

RESUMO

Quantitative phylogenetic methods have been used to study the evolutionary relationships and divergence times of biological species, and recently, these have also been applied to linguistic data to elucidate the evolutionary history of language families. In biology, the factors driving macroevolutionary processes are assumed to be either mainly biotic (the Red Queen model) or mainly abiotic (the Court Jester model) or a combination of both. The applicability of these models is assumed to depend on the temporal and spatial scale observed as biotic factors act on species divergence faster and in smaller spatial scale than the abiotic factors. Here, we used the Uralic language family to investigate whether both 'biotic' interactions (i.e. cultural interactions) and abiotic changes (i.e. climatic fluctuations) are also connected to language diversification. We estimated the times of divergence using Bayesian phylogenetics with a relaxed-clock method and related our results to climatic, historical and archaeological information. Our timing results paralleled the previous linguistic studies but suggested a later divergence of Finno-Ugric, Finnic and Saami languages. Some of the divergences co-occurred with climatic fluctuation and some with cultural interaction and migrations of populations. Thus, we suggest that both 'biotic' and abiotic factors contribute either directly or indirectly to the diversification of languages and that both models can be applied when studying language evolution.


Assuntos
Mudança Climática , Cultura , Linguística
5.
Mol Phylogenet Evol ; 65(2): 786-91, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22796530

RESUMO

Within butterflies and moths, adult hematophagy is limited to species within the vampire moth genus Calyptra. These moths are placed within the subfamily Calpinae, whose other members are known to exhibit a broad range of feeding behaviors including those that can be considered 'piercers' of fruits or other hosts and 'tear feeders'. Here, we reconstruct a phylogenetic hypothesis of Calpinae using molecular data to test whether hematophagy in Calyptra arose from plant or animal-related behaviors. We use a Bayesian method of ancestral state reconstruction to determine the most likely feeding behaviors for the subtribes and genera within this lineage.


Assuntos
Comportamento Alimentar , Mariposas/classificação , Filogenia , Animais , Teorema de Bayes , Núcleo Celular/genética , DNA Mitocondrial/genética , Frutas , Genes de Insetos , Funções Verossimilhança , Modelos Genéticos , Mariposas/genética
6.
Neotrop Entomol ; 41(6): 461-7, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23949670

RESUMO

This paper discusses the systematic position of the rare and endangered satyrine butterfly Caenoptychia boulleti Le Cerf, the only included species in Caenoptychia (type species), based on adult morphology and molecular data. The results showed that Caenoptychia Le Cerf belongs to the Euptychia Hübner clade, and the genus is synonymized with Euptychia, new synonymy. Euptychia boulleti (Le Cerf) is a new combination. The male genitalia of E. boulleti showed at least one important synapomorphy with the other species of Euptychia, which is the presence of a posterior projection of the tegumen above the uncus. Molecular data reinforces the position of Caenoptychia within the genus Euptychia.


Assuntos
Borboletas/anatomia & histologia , Borboletas/classificação , Animais , Brasil , Feminino , Masculino
7.
Neotrop Entomol ; 40(1): 1-13, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21437476

RESUMO

We review the various proposals of evolutionary and classification schemes for Satyrinae and particularly Euptychiina butterflies, assessing progress and prospects of research for the group. Among the highlights is the proposal to include Morphini, Brassolini and Amathusiini as part of Satyrinae. Although it is clear that this hypothesis requires further investigation, phylogenetic studies recently conducted recover this clade as part of Satyrinae with high support. The phylogenetic analyses for Euptychiina carried out to date recover the monophyly of the group and have identified a variety of genera as non-monophyletic. Further work is necessary to resolve the position of the subtribe and the evolutionary relationships of several genera.


Assuntos
Borboletas/classificação , Animais , Borboletas/anatomia & histologia , Lepidópteros/classificação , Filogenia
8.
Neotrop. entomol ; 40(1): 1-13, Jan.-Feb. 2011. ilus, tab
Artigo em Inglês | LILACS | ID: lil-578828

RESUMO

We review the various proposals of evolutionary and classification schemes for Satyrinae and particularly Euptychiina butterflies, assessing progress and prospects of research for the group. Among the highlights is the proposal to include Morphini, Brassolini and Amathusiini as part of Satyrinae. Although it is clear that this hypothesis requires further investigation, phylogenetic studies recently conducted recover this clade as part of Satyrinae with high support. The phylogenetic analyses for Euptychiina carried out to date recover the monophyly of the group and have identified a variety of genera as non-monophyletic. Further work is necessary to resolve the position of the subtribe and the evolutionary relationships of several genera.


Assuntos
Animais , Borboletas/classificação , Borboletas/anatomia & histologia , Lepidópteros/classificação , Filogenia
9.
J Environ Manage ; 86(4): 712-20, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17287069

RESUMO

The causes for the failure in enforcement of environmental regulations at the Giap Lai pyrite mine in northern Vietnam are considered and the environmental impacts that are associated with this mine are evaluated. It is shown that sulphide-rich tailings and waste rock in the mining area represent significant sources of acid rock drainage (ARD). The ARD is causing elevated metal levels in downstream water bodies, which in turn, represent a threat to both human health and to aquatic ecosystems. Metal concentrations in impacted surface waters have increased after mine closure, suggesting that impacts are becoming progressively more serious. No post-closure, remediation measures have been applied at the mine, in spite of the existence of environmental legislation and both central and regional institutions charged with environmental supervision and control. The research presented here provides further emphasis for the recommendation that, while government institutions may need to be strengthened, and environmental regulations need to be in place, true on the ground improvement in environmental quality in Vietnam and in many other developing countries require an increased focus on promoting public awareness of industrial environmental issues.


Assuntos
Sedimentos Geológicos/análise , Resíduos Industriais/análise , Ferro , Metais/análise , Mineração , Sulfetos , Poluentes Químicos da Água/análise , Meio Ambiente , Monitoramento Ambiental , Poluição Ambiental/legislação & jurisprudência , Regulamentação Governamental , Mineração/legislação & jurisprudência , Rios/química , Vietnã
10.
J Evol Biol ; 20(6): 2181-91, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17887973

RESUMO

The relative importance of dispersal and vicariance in the diversification of taxa has been much debated. Within butterflies, a few studies published so far have demonstrated vicariant patterns at the global level. We studied the historical biogeography of the genus Junonia (Nymphalidae: Nymphalinae) at the intercontinental level based on a molecular phylogeny. The genus is distributed over all major biogeographical regions of the world except the Palaearctic. We found dispersal to be the dominant process in the diversification of the genus. The genus originated and started diversifying in Africa about 20 Ma and soon after dispersed into Asia possibly through the Arabian Peninsula. From Asia, there were dispersals into Africa and Australasia, all around 5 Ma. The origin of the New World species is ambiguous; the ancestral may have dispersed from Asia via the Beringian Strait or from Africa over the Atlantic, about 3 Ma. We found no evidence for vicariance at the intercontinental scale. We argue that dispersal is as important as vicariance, if not more, in the global diversification of butterflies.


Assuntos
Borboletas/classificação , Borboletas/genética , África , Animais , Especiação Genética , Geografia , Filogenia
11.
J Evol Biol ; 19(2): 483-91, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16599924

RESUMO

The ability of insects to utilize different host plants has been suggested to be a dynamic and transient phase. During or after this phase, species can shift to novel host plants or respecialize on ancestral ones. Expanding the range of host plants might also be a factor leading to higher levels of net speciation rates. In this paper, we have studied the possible importance of host plant range for diversification in the genus Polygonia (Nymphalidae, Nymphalini). We have compared species richness between sistergroups in order to find out if there are any differences in number of species between clades including species that utilize only the ancestral host plants ('urticalean rosids') and their sisterclades with a broader (or in some cases potentially broader) host plant repertoire. Four comparisons could be made, and although these are not all phylogenetically or statistically independent, all showed clades including butterfly species using other or additional host plants than the urticalean rosids to be more species-rich than their sisterclade restricted to the ancestral host plants. These results are consistent with the theory that expansions in host plant range are involved in the process of diversification in butterflies and other phytophagous insects, in line with the general theory that plasticity may drive speciation.


Assuntos
Borboletas/fisiologia , Variação Genética , Plantas/parasitologia , Animais , Borboletas/classificação , Borboletas/genética , Clima , Evolução Molecular , Interações Hospedeiro-Parasita , Filogenia , Suécia
12.
J Environ Manage ; 65(2): 165-79, 2002 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-12197078

RESUMO

This paper considers technical measures and policy initiatives needed to improve environmental management in the Portovelo-Zaruma mining district of southern Ecuador. In this area, gold is mined by a large number of small-scale and artisanal operators, and discharges of cyanide and metal-laden tailings have had a severe impact on the shared Ecuadorian-Peruvian Puyango river system. It is shown to be technically possible to confine mining waste and tailings at a reasonable cost. However, the complex topography of the mining district forces tailings management to be communal, where all operators are connected to one central tailings impoundment. This, in turn, implies two things: (i) that a large number of operators must agree to pool resources to bring such a facility into reality; and (ii) that miners must move away from rudimentary operations that survive on a day-to-day basis, towards bigger, mechanized and longer-term sustainable operations that are based on proven ore reserves. It is deemed unlikely that existing environmental regulations and the provision of technical solutions will be sufficient to resolve the environmental problems. Important impediments relate to the limited financial resources available to each individual miner and the problems of pooling these resources, and to the fact that the main impacts of pollution are suffered downstream of the mining district and, hence, do not affect the miners themselves. Three policy measures are therefore suggested. First, the enforcement of existing regulations must be improved, and this may be achieved by the strengthening of the central authority charged with supervision and control of mining activities. Second, local government involvement and local public participation in environmental management needs to be promoted. Third, a clear policy should be defined which promotes the reorganisation of small operations into larger units that are strong enough to sustain rational exploration and environmental obligations. The case study suggests that mining policy in lesser-developed countries should develop to enable small-scale and artisanal miners to form entities that are of a sufficiently large scale to allow adequate and cost-effective environmental protection.


Assuntos
Meio Ambiente , Poluição Ambiental/prevenção & controle , Mineração , Análise Custo-Benefício , Tomada de Decisões , Equador , Poluição Ambiental/economia , Fenômenos Geológicos , Geologia , Ouro , Humanos , Formulação de Políticas , Opinião Pública
13.
Sci Total Environ ; 278(1-3): 239-61, 2001 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-11669272

RESUMO

Gold mining in the Portovelo-Zaruma district in southern Ecuador is causing considerable environmental impacts; the most important ones are related to the discharge of cyanide, mercury and metal rich tailings into rivers of the Puyango catchment area. Cyanide and metal levels in rivers regularly exceed environmental quality criteria. The contamination impacts biodiversity, with cyanide causing a direct lethal effect on biota close to source and metal contaminants considerably reducing aquatic biodiversity further downstream. It is shown that the prevailing neutral or slightly alkaline conditions of the rivers ensure that metals are mainly associated with sediment. However, elevated metal levels in bottom living larvae collected from contaminated sites suggest that these sediment bound metals are readily bioavailable. Leaching experiments indicate that the relative ease by which metals are taken up by larvae is related to the speciation of sediment associated metals. It is further shown that large amounts of metals, which are bound to suspended sediment under ambient pH conditions, enter the dissolved and directly bioavailable state in more acidic conditions. Metal levels in carnivorous fish were found to be modestly elevated only, with the exception of mercury. Mercury levels exceeded 0.5 mg/kg in fish from both contaminated and uncontaminated sites, showing that both methylation and bioaccumulation of mercury are occurring in the Puyango river basin.


Assuntos
Ecossistema , Cadeia Alimentar , Ouro , Metais Pesados/análise , Mineração , Poluentes Químicos da Água/análise , Animais , Disponibilidade Biológica , Equador , Monitoramento Ambiental , Peixes , Concentração de Íons de Hidrogênio , Metais Pesados/efeitos adversos , Dinâmica Populacional , Distribuição Tecidual , Poluentes Químicos da Água/efeitos adversos
14.
Evolution ; 55(3): 522-37, 2001 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-11327160

RESUMO

Butterflies in the tribe Melitaeini (Lepidoptera: Nymphalidae) are known to utilize host plants belonging to 16 families, although most host-plant records are from four families. Of the 16 host-plant families, 12 produce secondary plant metabolites called iridoids. Earlier studies have shown that larvae of several melitaeine species use iridoids as feeding stimulants and sequester these compounds for larval defense. I investigate the evolutionary history of host-plant use in the tribe Melitaeini by testing a recent phylogenetic hypothesis of 65 species representing the four major species groups of the tribe. By simple character optimization of host-plant families and presence/absence of iridoids in the host plants, I find that plant chemistry is a more conservative trait than plant taxonomy. The ancestral host plant(s) of the entire tribe most likely contained iridoids and were likely to be in the plant family Plantaginaceae. A major host shift from plants containing iridoids to plants not containing iridoids has happened three times independently. The results show that the evolution of host-plant use in melitaeines has been (and still is) a dynamic process when considering plant taxonomy, but is relatively stable when considering host-plant chemistry.


Assuntos
Borboletas/genética , Filogenia , Plantas/anatomia & histologia , Plantas/genética , Animais , DNA Mitocondrial/genética , DNA de Plantas/genética , Feminino , Glucosídeos/metabolismo , Iridoides , Plantas/metabolismo , Piranos/metabolismo
15.
J Invest Dermatol ; 113(4): 547-53, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10504439

RESUMO

The incidence of skin cancer is increasing rapidly and sunscreens have been recommended in order to reduce damage from sunlight. In this investigation we have studied the change in the absorption spectrum of some photoactive organic species in sunscreens after ultraviolet A and ultraviolet B irradiation in a dose normally encountered during a full day in the sun. Samples of a number of photoactive compounds commonly used in sunscreens were irradiated with ultraviolet A and ultraviolet B light. A UVASUN 2000 MUTZHAS sunlamp was used for ultraviolet A irradiation and an Esshå Corona mini, equipped with two Philips TL12 20 W lamps, was used as the ultraviolet B source. The ultraviolet A dose was 100 J per cm2. The ultraviolet B dose corresponded to 20 minimal erythema doses. The absorption spectra of the compounds were recorded before and after irradiation. The absorbance of 2-ethylhexyl 4-methoxycinnamate was reduced significantly, whereas 3-(4-methylbenzyliden)camphor seemed to be rather stable. The benzophenones studied seemed to be relatively stable. In the case of 4-tert. butyl-4'-methoxy-dibenzoylmethane there was a rapid decrease in the ultraviolet A absorption leading to unsatisfactory protection in the ultraviolet A region. 4-Isopropyl-dibenzoylmethane also lost most of its ultraviolet protective capacity after irradiation with ultraviolet A. Ultraviolet B seemed to have a minor effect on all the samples. It is important for the clinician not only to know the initial absorption spectrum in the ultraviolet region for a specific sunscreen substance, but also whether it is altered during irradiation and in what way. This study including gas chromatography and mass spectrometry analysis indicates that some of the photoactive organic species commonly used today in sunscreens are unstable following ultraviolet irradiation.


Assuntos
Protetores Solares/efeitos da radiação , Raios Ultravioleta , Estabilidade de Medicamentos , Espectrofotometria Ultravioleta , Protetores Solares/química
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