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1.
PLoS One ; 18(11): e0293083, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37939028

RESUMO

Biodiversity loss is a major global challenge and minimizing extinction rates is the goal of several multilateral environmental agreements. Policy decisions require comprehensive, spatially explicit information on species' distributions and threats. We present an analysis of the conservation status of 14,669 European terrestrial, freshwater and marine species (ca. 10% of the continental fauna and flora), including all vertebrates and selected groups of invertebrates and plants. Our results reveal that 19% of European species are threatened with extinction, with higher extinction risks for plants (27%) and invertebrates (24%) compared to vertebrates (18%). These numbers exceed recent IPBES (Intergovernmental Platform on Biodiversity and Ecosystem Services) assumptions of extinction risk. Changes in agricultural practices and associated habitat loss, overharvesting, pollution and development are major threats to biodiversity. Maintaining and restoring sustainable land and water use practices is crucial to minimize future biodiversity declines.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Biodiversidade , Vertebrados , Invertebrados , Plantas , Extinção Biológica , Espécies em Perigo de Extinção
2.
Science ; 358(6365): 879-880, 2017 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-29146802
5.
Mitochondrial DNA ; 22 Suppl 1: 27-36, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21980985

RESUMO

DNA barcoding is a method promising fast and accurate identification of animal species based on the sequencing of the mitochondrial c oxidase subunit (COI) gene. In this study, we explore the prospects for DNA barcoding in one particular fish group, the billfishes (suborder Xiphioidei--swordfish, marlins, spearfishes, and sailfish). We sequenced the mitochondrial COI gene from 296 individuals from the 10 currently recognized species of billfishes, and combined these data with a further 57 sequences from previously published projects. We also sequenced the rhodopsin gene from a subset of 72 individuals to allow comparison of mitochondrial results against a nuclear marker. Five of the 10 species are readily distinguishable by COI barcodes. Of the rest, the striped marlin (Kajikia audax) and white marlin (K. albida) show highly similar sequences and are not unambiguously distinguishable by barcodes alone, likewise are the three spearfishes Tetrapturus angustirostris, T. belone, and T. pfluegeri. We discuss the taxonomic status of these species groups in light of our and other data, molecular and morphological.


Assuntos
Código de Barras de DNA Taxonômico/métodos , Perciformes/classificação , Perciformes/genética , Animais , DNA/análise , DNA/genética , Código de Barras de DNA Taxonômico/normas , DNA Mitocondrial/análise , DNA Mitocondrial/genética , Complexo IV da Cadeia de Transporte de Elétrons/genética , Variação Genética , Filogenia , Reação em Cadeia da Polimerase/métodos , Rodopsina/genética , Análise de Sequência de DNA , Especificidade da Espécie
6.
Evolution ; 61(11): 2570-83, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17725625

RESUMO

We have previously documented multiple, independent origins of placentas in the fish family Poeciliidae. Here we summarize similar analyses of fishes in the family Zenarchopteridae. This family includes three live-bearing genera. Earlier studies documented the presence of superfetation, or the ability to carry multiple litters of young in different stages of development in the same ovary, in some species in all three genera. There is also one earlier report of matrotrophy, or extensive postfertilization maternal provisioning, in two of these genera. We present detailed life-history data for approximately half of the species in all three genera and combine them with the best available phylogeny to make inferences about the pattern of life-history evolution within this family. Three species of Hemirhamphodon have superfetation but lack matrotrophy. Most species in Nomorhamphus and Dermogenys either lack superfetation and matrotrophy or have both superfetation and matrotrophy. Our phylogenetic analysis shows that matrotrophy may have evolved independently in each genus. In Dermogenys, matrotrophic species produce fewer, larger offspring than nonmatrotrophic species. In Nomorhamphus; matrotrophic species instead produce more and smaller offspring than lecithotrophic species. However, the matrotrophic species in both genera have significantly smaller masses of reproductive tissue relative to their body sizes. All aspects of these results are duplicated in the fish family Poeciliidae. We discuss the possible adaptive significance of matrotrophy in the light of these new results. The two families together present a remarkable opportunity to study the evolution of a complex trait because they contain multiple, independent origins of the trait that often include close relatives that vary in either the presence or absence of the matrotrophy or in the degree to which matrotrophy is developed. These are the raw materials that are required for either an analysis of the adaptive significance of the trait or for studies of the genetic mechanisms that underlie the evolution of the trait.


Assuntos
Adaptação Biológica/fisiologia , Beloniformes/fisiologia , Evolução Biológica , Ciprinodontiformes/fisiologia , Estágios do Ciclo de Vida/fisiologia , Animais , Tamanho Corporal , Feminino , Fertilização , Filogenia , Fatores de Tempo
7.
Integr Comp Biol ; 44(5): 366-77, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21676722

RESUMO

To investigate jaw evolution in beloniform fishes, we reconstructed the phylogeny of 54 species using fragments of two nuclear (RAG2 and Tmo-4C4) and two mitochondrial (cytochrome b and 16S rRNA) genes. Our total molecular evidence topology refutes the monophyly of needlefishes (Belonidae) and halfbeaks (Hemiramphidae), but supports the monophyly of flyingfishes (Exocoetidae) and sauries (Scomberesocidae). Flyingfishes are nested within halfbeaks, and sauries are nested within needlefishes. Optimization of jaw characters on the tree reveals a diverse array of evolutionary changes in ontogeny. During their development, needlefishes pass through a "halfbeak" stage that closely resembles the adult condition in the hemiramphid halfbeaks. The reconstruction of jaw transitions falsifies the hypothesis that halfbeaks are paedomorphic derivatives of needlefishes. Instead, halfbeaks make up a basal paraphyletic grade within beloniforms, and the needlefish jaw morphology is relatively derived. The parallel between needlefish ontogeny and beloniform phylogeny is discussed, and clades amenable to future morphological analysis are proposed.

8.
Rev. biol. trop ; 49(Supl.1): 111-115, jul. 2001. ilus
Artigo em Inglês | LILACS | ID: lil-502467

RESUMO

Ammodytoides gilli (Bean, 1895) is the correct name for the tropical eastern Pacific sand lance. Its range is extended from Cabo San Lucas, Baja California south to Panama, Ecuador, and the Galapagos Islands. Ammodytes lucasanus Beebe and Tee-Van, 1938 is a junior synonym. Types of both nominal species were re-examined. The species is redescribed based on 50 specimens (42.3-115 mm SL) from 12 lots and is compared with other known species of Ammodytoides. Changes in ontogeny from the smallest known specimen (42.3 mm SL, illustrated) are detailed including reduction in the posterior dorsal fin lobe and development of branched dorsal and anal fin rays.


Assuntos
Animais , Perciformes/classificação , Oceano Pacífico , Perciformes/anatomia & histologia
9.
Rev. biol. trop ; 49(Supl.1): 39-49, jul. 2001. ilus, tab
Artigo em Inglês | LILACS | ID: lil-502474

RESUMO

The tropical eastern Pacific halfbeak previously considered conspecific with the western Atlantic Hyporhamphus unifasciatus (Ranzani 1842) is described as a new species, H. naos. It resembles H. meeki from the Atlantic and Gulf coasts of the United States in number of gill rakers on the first arch (usually 32-36, mean 33.6), more than in H. unifasciatus (usually 29-32, mean 30.6), but fewer than in other sympatric species of eastern Pacific Hyporhamphus. Results of a three-treatment ANCOVA (H. naos, H. meeki, and H. unifasciatus) show significant differences in slopes and means for all 14 morphometric characters examined, 9 of 14 characters comparing H. naos with H. unifasciatus, and 7 of 14 comparing H. naos with H. meeki. Protein electrophoretic patterns clearly distinguish all three species with a number of fixed allelic differences.


Assuntos
Animais , Beloniformes/classificação , Alelos , Análise de Variância , Beloniformes/genética , Eletroforese , Oceano Pacífico , Proteínas/análise
10.
Rev. biol. trop ; 49(Supl.1): 51-57, jul. 2001. ilus, tab
Artigo em Inglês | LILACS | ID: lil-502473

RESUMO

Tylosurus pacificus (Steindachner, 1876) is confirmed to have full species rank based on: 1) sympatry with T. acus melanotus at Isla Gorgona and in Panamá; 2) level of morphological differentiation in numbers of vertebrae, dorsal and anal fin rays; and 3) level of mtDNA differentiation. The eastern Pacific agujon needlefish is found from the Gulf of California, Mexico, to Peru, including the Galápagos Islands.


Assuntos
Animais , Beloniformes/classificação , DNA Mitocondrial/análise , Beloniformes/genética , Oceano Pacífico
11.
Cladistics ; 1(2): 141-158, 1985 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34965672

RESUMO

Abstract- A cladistic analysis of the eighteen species of Spanish mackerels (Scomberomorus) was conducted using the double-lined mackerel (Grammatorcynus) as the outgroup. Based on fifty-eight osteological and morphological characters, six species groups are recognized. Comparisons of the cladogram for the regalis species group were made with a cladogram of the nine species of parasitic copepods that infest the six members of the regalis group. Incongruences were analyzed. The parasite tree was then "forced" onto the host cladogram to determine which evolutionary events of the parasites could be explained by evolutionary events of the hosts. Hypotheses of coevolution are supported in some cases, hypotheses of dispersal are proposed in others.

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