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Oxidase I (oxidase + i)
Kinds of Oxidase I Terms modified by Oxidase I Selected AbstractsA molecular phylogenetic framework for the evolution of parasitic strategies in cymothoid isopods (Crustacea)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 1 2008V. Ketmaier Abstract The parasitic isopods belonging to the family Cymothoidae attach under the scales, in the gills or on the tongue of their fish hosts, exhibiting distinctive life-histories and morphological modifications. According to conventional views, the three parasitic types (scale-, gill-, and mouth-dwellers) correspond to three distinct lineages. In this study, we have used fragments of two mitochondrial genes (large ribosomal DNA subunit, 16S rRNA, and cytochrome oxidase I) and two species for each of the three parasitic habits to present a preliminary hypothesis on the evolutionary history of the family. Our molecular data support the monophyly of the family but suggest that , contrary to what was previously believed , the more specialized mouth- and gill-inhabiting species are not necessarily derived from scale-dwelling ones. Zusammenfassung Die parasitischen Isopoden aus der Familie der Cymothoidae heften sich an die Schuppen, Kiemen oder an die Zunge ihrer Fischwirte; dabei zeigen sie unterschiedlichen Lebenszyklen und morphologische Besonderheiten. Bisherigen Untersuchungen zufolge gehören die drei Parasitentypen (Schuppen-, Kiemen- und Mundparasiten) zu drei unterschiedlichen phylogenetischen Linien. In der vorliegenden Untersuchung haben wir Fragmente von zwei mitochondrialen Genen (die gro,e ribosomale DNA - Untereinheit, 16s rRNA und Cytochrome Oxidase I, COI) von je zwei Vertretern der drei Parasitentypen untersucht, um eine vorläufige Hypothese über die evolutionären Beziehungen innerhalb der Familie aufzustellen. Unsere molekularbiologischen Ergebnisse unterstützen die Monophylie dieser Familie. Sie unterstützen jedoch nicht die bisherige Annahme, dass die stärker spezialisierten maul- und kiemenparasitierenden Arten von den schuppenparasitierenden Arten abstammen. [source] Reconstructing the origins of praying mantises (Dictyoptera, Mantodea): the roles of Gondwanan vicariance and morphological convergenceCLADISTICS, Issue 5 2009Gavin J. Svenson A comprehensive taxonomic sampling of Mantodea (praying mantises), covering virtually all higher-level groups, was assembled to reconstruct the phylogeny of the order. Sequence data were generated from five mitochondrial and four nuclear loci (12S rRNA, 16S rRNA, 18S rRNA, 28S rRNA, Histone III, Cytochrome Oxidase I & II, NADH dehydrogenase subunit 4, and Wingless) for 329 mantis exemplars along with seven cockroach and eight termite species. Only seven of 14 families, 14 of 33 subfamilies, and seven of 14 tribes were recovered as monophyletic, indicating that phylogeny is largely incongruent with classification. Mapping biogeographical regions on the phylogeny demonstrated that our results adhere closer to biogeographical distributions than to classification. Specific patterns in distribution suggest that major morphological convergences have confounded taxonomists' ability to reconstruct natural groups. A major revision of higher-level relationships is in order through a comprehensive investigation of morphology and molecular data. We found that major mantis lineages diverged prior to and during the isolation of geographical regions and subsequent ecomorphic specializations within these regions may have led to convergences in morphology. Divergence time estimation places the origin of Mantodea at the beginning of the Jurassic with most modern mantises originating on Gondwana in the Cretaceous. The first major divergence among modern mantises occurred as a result of the north,south splitting of South America and Africa. Subsequent divergences resulted from the breakup of Gondwana. The position of the Indian subcontinent appears to be central to the diversification of Afrotropical and Indomalayan mantises while Antarctica may have served as the conduit for the mantis invasions into South America and Australasia. When India separated from Antarctica and drifted north it distributed mantis lineages back into the Afrotropics and carried a diverse taxonomic assemblage to Asia. [source] Tracing recent invasions of the Ponto-Caspian mysid shrimp Hemimysis anomala across Europe and to North America with mitochondrial DNADIVERSITY AND DISTRIBUTIONS, Issue 2 2008Asta Audzijonyte ABSTRACT The mysid crustacean Hemimysis anomala (,bloody-red shrimp') is one of the most recent participants in the invasion of European inland waters by Ponto-Caspian species. Recently the species also became established in England and the Laurentian Great Lakes of North America. Using information from mitochondrial cytochrome oxidase I (COI) gene sequences, we traced the invasion pathways of H. anomala; the inferences were enabled by the observed phylogeographical subdivision among the source area populations in the estuaries of the Ponto-Caspian basin. The data distinguish two routes to northern and western Europe used by distinct lineages. One route has been to and through the Baltic Sea and further to the Rhine delta, probably from a population intentionally introduced to a Lithuanian water reservoir from the lower Dnieper River (NW Black Sea area) in 1960. The other lineage is derived from the Danube delta and has spread across the continent up the Danube River and further through the Main,Danube canal down to the Rhine River delta. Only the Danube lineage was found in England and in North America. The two lineages appear to have met secondarily and are now found intermixed at several sites in NW Europe, including the Rhine and waters linked with the man-made Mittellandkanal that interconnects the Rhine and Baltic drainage systems. [source] Integrating DNA data and traditional taxonomy to streamline biodiversity assessment: an example from edaphic beetles in the Klamath ecoregion, California, USADIVERSITY AND DISTRIBUTIONS, Issue 5 2006Ryan M. Caesar ABSTRACT Conservation and land management decisions may be misguided by inaccurate or misinterpreted knowledge of biodiversity. Non-systematists often lack taxonomic expertise necessary for an accurate assessment of biodiversity. Additionally, there are far too few taxonomists to contribute significantly to the task of identifying species for specimens collected in biodiversity studies. While species level identification is desirable for making informed management decisions concerning biodiversity, little progress has been made to reduce this taxonomic deficiency. Involvement of non-systematists in the identification process could hasten species identification. Incorporation of DNA sequence data has been recognized as one way to enhance biodiversity assessment and species identification. DNA data are now technologically and economically feasible for most scientists to apply in biodiversity studies. However, its use is not widespread and means of its application has not been extensively addressed. This paper illustrates how such data can be used to hasten biodiversity assessment of species using a little-known group of edaphic beetles. Partial mitochondrial cytochrome oxidase I was sequenced for 171 individuals of feather-wing beetles (Coleoptera: Ptiliidae) from the Klamath ecoregion, which is part of a biodiversity hotspot, the California Floristic Province. A phylogram of these data was reconstructed via parsimony and the strict consensus of 28,000 equally parsimonious trees was well resolved except for peripheral nodes. Forty-two voucher specimens were selected for further identification from clades that were associated with many synonymous and non-synonymous nucleotide changes. A ptiliid taxonomic expert identified nine species that corresponded to monophyletic groups. These results allowed for a more accurate assessment of ptiliid species diversity in the Klamath ecoregion. In addition, we found that the number of amino acid changes or percentage nucleotide difference did not associate with species limits. This study demonstrates that the complementary use of taxonomic expertise and molecular data can improve both the speed and the accuracy of species-level biodiversity assessment. We believe this represents a means for non-systematists to collaborate directly with taxonomists in species identification and represents an improvement over methods that rely solely on parataxonomy or sequence data. [source] Genetic structure of Japanese populations of an ambrosia beetle, Xylosandrus germanus (Curculionidae: Scolytinae)ENTOMOLOGICAL SCIENCE, Issue 3 2008Masaaki ITO Abstract We examined the genetic structures of 13 Japanese populations of an ambrosia beetle, Xylosandrus germanus (Curculionidae: Scolytinae), to understand the effects of geographical barriers on the colonization dynamics of this species. The genetic structure was studied using portions of the mitochondrial cytochrome oxidase I (COI) gene. A phylogenetic analysis revealed three distinct lineages (clades A, B and C) within X. germanus. Clade A contained 21 haplotypes from all 13 populations; whereas clade B contained eight haplotypes from Hokkaido (Sapporo and Furano), Iwate and Nagano populations; and clade C contained only a single a haplotype from the Hokkaido (Furano) population. In the analysis of molecular variance (amova), the greatest amount of genetic variation was detected between populations in Hokkaido and those in Honshu and other southern islands. Between these two groups of populations, all the values of the coefficient of gene differentiation were significantly larger than zero, except for the Hokkaido (Sapporo) versus Nagano comparison. Our results confirm that for X. germanus, gene flow has been interrupted between Hokkaido and Honshu since the last glacial maximum. [source] Real-time PCR assay for the identification of Thrips palmi,EPPO BULLETIN, Issue 1 2005L. F. F. Kox Since Thrips palmi became a regulated pest for most European countries, inspections at points of entry into Europe and monitoring in Europe have intensified not only for T. palmi but also for thrips as a whole. Morphological identification of thrips is performed on adults and to a lesser extent on second-stage larvae only, because no adequate identification keys for the separation of species based on the characteristics of eggs, first-stage larvae, pre-pupae or pupae are available. We have developed a real-time PCR assay based on TaqMan. A T. palmi -specific set of primers and probe were selected within the mitochondrial cytochrome oxidase I (COI) gene. The specificity of the assay was assessed using 15 specimens of Thrips palmi and 61 specimens of 23 other thrips species commonly occuring in Europe. All T. palmi specimens were detected, and no cross reactions with other thrips were observed. The method was tested on single larvae and adults and proved to be applicable for both those stages of T. palmi. [source] HISTORIC CYCLES OF FRAGMENTATION AND EXPANSION IN PARNASSIUS SMINTHEUS (PAPILIONIDAE) INFERRED USING MITOCHONDRIAL DNAEVOLUTION, Issue 1 2004Eric G. DeChaine Abstract Climate oscillations of the Quaternary drove the repeated expansion and contraction of ecosystems. Alpine organisms were probably isolated in sky island refugia during warm interglacials, such as now, and expanded their range by migrating down-slope during glacial periods. We used population genetic and phylogenetic approaches to infer how paleoclimatic events influenced the distribution of genetic variation in the predominantly alpine butterfly Parnassius smintheus. We sequenced a 789 bp region of cytochrome oxidase I for 385 individuals from 20 locations throughout the Rocky Mountains, ranging from southern Colorado to northern Montana. Analyses revealed at lease two centers of diversity in the northern and southern Rocky Mountains and strong population structure. Nested clade analysis suggested that the species experienced repeated cycles of population expansion and fragmentation. The estimated ages of these events, assuming a molecular clock, corresponded with paleoclimatic data on habitat expansion and contraction over the past 400,000 years. We propose that alpine butterflies persisted in an archipelago of isolated sky islands during interglacials and that populations expanded and became more connected during cold glacial periods. An archipelago model implies that the effects of genetic drift and selection varied among populations, depending on their latitude, area, and local environment. Alpine organisms are sensitive indicators of climate change and their history can be used to predict how high-elevation ecosystems might respond to further climate warming. [source] Lessons from leeches: a call for DNA barcoding in the labEVOLUTION AND DEVELOPMENT, Issue 6 2006Alexandra E. Bely SUMMARY Many evolution of development labs study organisms that must be periodically collected from the wild. Whenever this is the case, there is the risk that different field collections will recover genetically different strains or cryptic species. Ignoring this potential for genetic variation may introduce an uncontrolled source of experimental variability, leading to confusion or misinterpretation of the results. Leeches in the genus Helobdella have been a workhorse of annelid developmental biology for 30 years. Nearly all early Helobdella research was based on a single isolate, but in recent years isolates from multiple field collections and multiple sites across the country have been used. To assess the genetic distinctness of different isolates, we obtained specimens from most Helobdella laboratory cultures currently or recently in use and from some of their source field sites. From these samples, we sequenced part of the mitochondrial gene cytochrome oxidase I (COI). Sequence divergences and phylogenetic analyses reveal that, collectively, the Helobdella development community has worked on five distinct species from two major clades. Morphologically similar isolates that were thought to represent the same species (H. robusta) actually represent three species, two of which coexist at the same locality. Another isolate represents part of a species complex (the "H. triserialis" complex), and yet another is an invasive species (H. europaea). We caution researchers similarly working on multiple wild-collected isolates to preserve voucher specimens and to obtain from these a molecular "barcode," such as a COI gene sequence, to reveal genetic variation in animals used for research. [source] Purification and properties of a new Brevibacterium sterolicum cholesterol oxidase produced by E. coli MM294/pnH10FEMS MICROBIOLOGY LETTERS, Issue 2 2002Kinya Fujishiro Abstract A gene encoding a cholesterol oxidase from Brevibacterium sterolicum nov. sp. ATCC21387 was isolated by an expression cloning method and highly expressed by a recombinant strain Escherichia coli MM294/pnH10. The purified cholesterol oxidase was a typical flavoprotein with a molecular mass of 46.5 kDa, absorption peaks at 280, 360, and 450 nm. Optimum pH and temperature were found at pH 6.5 and 55°C, respectively. The enzyme acted on 3,-hydroxysteroids such as cholesterol, pregnenolone, and ,-sitosterol at high rates, but on dehydro- epi -androsterone to a lesser degree. The molecular and catalytic properties were different from those of cholesterol oxidase I, which was initially discovered in B. sterolicum nov. sp. ATCC21387. The new enzyme, designated cholesterol oxidase II, was distinguished by its high affinity toward cholesterol (Km= 30,M). [source] m.6267G>A: a recurrent mutation in the human mitochondrial DNA that reduces cytochrome c oxidase activity and is associated with tumors,HUMAN MUTATION, Issue 6 2006M. Esther Gallardo Abstract Complete sequencing of the mitochondrial genome of 13 cell lines derived from a variety of human cancers revealed nine novel mitochondrial DNA (mtDNA) variations. One of them, m.6267G>A, is a recurrent mutation that introduces the Ala122Thr substitution in the mitochondrially encoded cytochrome c oxidase I (MT-CO1): p.MT-CO1: Ala122Thr (GenBank: NP_536845.1). Biochemical analysis of the original cell lines and the transmitochondrial cybrids generated by transferring mitochondrial DNAs to a common nuclear background, indicate that cytochrome c oxidase (COX) activity, respiration, and growth in galactose are impaired by the m.6267G>A mutation. This mutation, found twice in the cancer cell lines included in this study, has been also encountered in one out of 63 breast cancer samples, one out of 64 colon cancer samples, one out of 260 prostate cancer samples, and in one out of 15 pancreatic cancer cell lines. In all instances the m.6267G>A mutation was associated to different mtDNA haplogroups. These findings, contrast with the extremely low frequency of the m.6267G>A mutation in the normal population (1:2264) and its apparent absence in other pathologies, strongly suggesting that the m.6267G>A missense mutation is a recurrent mutation specifically associated with cancer. Hum Mutat 27(6), 575,582, 2006. © 2006 Wiley-Liss, Inc. [source] Population variability in Chironomus (Camptochironomus) species (Diptera, Nematocera) with a Holarctic distribution: evidence of mitochondrial gene flowINSECT MOLECULAR BIOLOGY, Issue 5 2002J. Martin Abstract Phylogenetic analysis of DNA sequences from mitochondrial (mt) genes (Cytochrome b and Cytochrome oxidase I) and one nuclear gene (globin 2b) was used for the investigation of Nearctic and Palearctic populations representing four Chironomus species of the subgenus Camptochironomus, namely C. biwaprimus, C. pallidivittatus, C. tentans sensu stricto and C. dilutus (the last two species constitute Holarctic C. tentans sensu lato). Phenograms constructed on the basis of mt sequences were not congruent with trees based on nuclear genes, or with morphological and cytological data. The mt tree divided the populations by continental region, rather than by the species groupings recognized by the other data sets. The incongruence is explained by mt gene flow resulting from hybridization between the sympatric species on each continent. Calculation of divergence times, based on the sequence data, suggest that C. tentans (s.l.) and C. pallidivittatus have both been in North America for about 2.5 My. [source] Genetic differentiation of Bemisia tabaci (Gennadius) (Hemiptera: Aleyrodidae) biotype Q based on mitochondrial DNA markersINSECT SCIENCE, Issue 2 2008Dong Chu Abstract In the present study, genetic differentiation of Bemisia tabaci (Gennadius) biotype Q was analyzed based on mitochondrial cytochrome oxidase I (mt COI) gene sequence. The results showed that B. tabaci biotype Q could be separated into two subclades, which were labeled as subclades Q1 and Q2. Subclade Q1 was probably indigenous to the regions around the Mediterranean area and subclade Q2 to Israel or Cyprus. It was because B. tabaci was composed of several genetically distinct groups with a strong geographical association between more closely related biotypes. Not all of the B. tabaci biotype Q in the non-Mediterranean countries come from the same regions. Until now, all B. tabaci biotype Q in China were grouped into subclade Q1. The B. tabaci biotype Q introduced into the US included both subclades Q1 and Q2. The genetic structure analysis showed higher genetic variation of subclade Q1 than that of subclade Q2. [source] After the deluge: mitochondrial DNA indicates Miocene radiation and Pliocene adaptation of tree and giant weta (Orthoptera: Anostostomatidae)JOURNAL OF BIOGEOGRAPHY, Issue 2 2005Steven A. Trewick Abstract Aim, New Zealand broke away from the margins of Gondwana c. 75 Ma. Since then, New Zealand taxa derived from the Gondwanan biota are thought to have been exposed first to a subtropical climate on a low lying terrain, then severe land reduction during the Oligocene marine transgression, followed by much cooler climates of the Pliocene and Pleistocene, at which time mountain ranges emerged. The biological consequence of New Zealand's geological and climatic history is not well understood, in particular the extent to which the Oligocene acted as a biological bottleneck remains unresolved. Methods, We used mitochondrial cytochrome oxidase I and 12S DNA sequences to examine the extent of diversity and inferred timing of speciation of New Zealand weta (Anostostomatidae), a group of Orthoptera with a Gondwanan distribution generally thought to be ancient inhabitants of New Zealand. Main conclusions, We hypothesize that at least three distinct groups of weta survived the Oligocene marine transgression and radiated subsequently. Speciation followed during the Miocene and radiation into new habitats occurred during the Pliocene when mountain building created novel environments. Patterns of genetic diversity within species reflect, in some instances, geographical subdivision in the Pliocene, and in other cases, Pleistocene range changes resulting from climate change. [source] Molecular evidence for dispersal rather than vicariance as the origin of flightless insect species on the Chatham Islands, New ZealandJOURNAL OF BIOGEOGRAPHY, Issue 5 2000Steven A. Trewick Abstract Aim The aim was to use mitochondrial DNA sequence data to test between vicariance and oversea dispersal explanations for the origin of the Chatham Islands biota. Location New Zealand and the Chatham Islands, separated by c. 800 km in the south-west Pacific Ocean. Methods DNA sequences from the mitochondrial gene cytochrome oxidase I (COI) were obtained from four genera of relatively large and flightless insects (Coleoptera, Geodorcus, Mecodema; Orthoptera,Talitropsis; Blattoidea,Celatoblatta). These were used to test alternative hypotheses for the origin of the Chatham taxa. Results Phylogenetic analysis revealed the Chatham taxa in each genus to be monophyletic. Genetic distances exhibited by these genera, between taxa found on the Chatham Islands and mainland New Zealand were relatively low (11.2, 2.8, 3.0 and 4.9%, respectively). Main conclusions Even allowing for variation in molecular evolutionary rates, these genetic distances indicate phylogenetic separation of New Zealand and Chatham insect lineages in the Pliocene (2,6 Ma). Such dates are more than one order of magnitude too recent to be explained by vicariant (tectonic) processes. Oversea dispersal from New Zealand to the Chatham Islands is implicated and this conclusion is in keeping with the taxonomy of the endemic avifauna, flora and fossil molluscan fauna. [source] Association with host mitochondrial haplotypes suggests that feminizing microsporidia lack horizontal transmissionJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 6 2003J. E. Ironside Abstract The amphipod crustacean Gammarus duebeni hosts two feminizing microsporidian parasites, Nosema granulosis and Microsporidium sp. Samples of G. duebeni were collected from three sites on the Scottish island of Great Cumbrae and screened for microsporidia using polymerase chain reaction. Associations between the prevalence of the two feminizing parasites and haplotypes of the host mitochondrial gene cytochrome oxidase I (COI) were investigated. The prevalence of both parasites varied significantly among the host's COI haplotypes, suggesting that horizontal transmission is rare or absent in the life cycles of the feminizing microsporidia and that all transmission must therefore be vertical. Life cycles in which all transmission is vertical are common among bacterial parasites but have never before been demonstrated in Eukaryotic parasites. [source] Selection of evolutionary models for phylogenetic hypothesis testing using parametric methodsJOURNAL OF EVOLUTIONARY BIOLOGY, Issue 4 2001B. C. Emerson Recent molecular studies have incorporated the parametric bootstrap method to test a priori hypotheses when the results of molecular based phylogenies are in conflict with these hypotheses. The parametric bootstrap requires the specification of a particular substitutional model, the parameters of which will be used to generate simulated, replicate DNA sequence data sets. It has been both suggested that, (a) the method appears robust to changes in the model of evolution, and alternatively that, (b) as realistic model of DNA substitution as possible should be used to avoid false rejection of a null hypothesis. Here we empirically evaluate the effect of suboptimal substitution models when testing hypotheses of monophyly with the parametric bootstrap using data sets of mtDNA cytochrome oxidase I and II (COI and COII) sequences for Macaronesian Calathus beetles, and mitochondrial 16S rDNA and nuclear ITS2 sequences for European Timarcha beetles. Whether a particular hypothesis of monophyly is rejected or accepted appears to be highly dependent on whether the nucleotide substitution model being used is optimal. It appears that a parameter rich model is either equally or less likely to reject a hypothesis of monophyly where the optimal model is unknown. A comparison of the performance of the Kishino,Hasegawa (KH) test shows it is not as severely affected by the use of suboptimal models, and overall it appears to be a less conservative method with a higher rate of failure to reject null hypotheses. [source] On the systematics of the fungus gnat subfamily Mycetophilinae (Diptera): a combined morphological and molecular approachJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 3 2009E. Rindal Abstract The phylogenetic relationships within the fungus gnat subfamily Mycetophilinae (Diptera) are addressed using a combined morphological and molecular approach. Twenty-four species, representing nine genera of the tribe Mycetophilini and 15 genera of the tribe Exechiini, were included in the study. Analyses include nucleotide sequences of mitochondrial (cytochrome oxidase I and 16S), and nuclear (18S and 28S rDNA) genes, in addition to 65 morphological characters. A combined parsimony analysis, including all characters, supports the monophyly of the subfamily Mycetophilinae and two of its tribes, Exechiini and Mycetophilini. There is also statistical support for a Mycetophila- group and a Phronia- group within the tribe Mycetophilini. The Phronia- group includes the genera Phronia, Macrobrachius and Trichonta. The Mycetophila- group includes the genera Mycetophila, Epicypta, Platurocypta, Sceptonia and Zygomyia. A Bayesian analysis based on the nucleotide sequences alone also support these clades within Mycetophilini except for the position of Dynatosoma which is recovered as the sister taxon to the Phronia- group. A somewhat different pattern, however, is observed for the tribe Exechiini , neither molecular data nor the combined data set support unambiguously any intergeneric relationships within Exechiini. Zusammenfassung Die phylogenetischen Verwandtschaftsbeziehungen innerhalb der Pilzmücken der Unterfamilie Mycetophilinae (Diptera) wurden mit einem kombinierten morphologischen und molekularen Ansatz untersucht. Vierundzwanzig Arten aus 9 Gattungen des Tribus Mycetophilini und 15 Gattungen des Tribus Exechiini wurden in die Untersuchungen einbezogen. Die Ergebnisse einer kombinierten kladistischen Analyse von 65 morphologischen Merkmalen und den Nukleotidsequenzen der mitochondrialen Cytochrom Oxidase I und 16S Gene sowie der 18S und 28S Gene des Kerngenoms stützen die Monophylie der Unterfamilie Mycetophilinae sowie der beiden Tribus Exechiini und Mycetophilini. Weiterhin hatten die Mycetophila- und die Phronia- Gruppe innerhalb des Tribus Mycetophilini hohe statistische Unterstützung. Die Phronia- Gruppe schlie,t die Gattungen Phronia, Macrobrachius und Trichonta und die Mycetophila- Gruppe die Gattungen Mycetophila, Epicypta, Platurocypta, Sceptonia und Zygomyia ein. Die Gattung Dynatosoma gruppierte ebenso in der Mycetophila- Gruppe. Die Bayesische Analyse der Nukleotidsequenzen stützt ebenfalls die Monophylie der oben genannten Gruppen innerhalb des Tribus Mycetophilini. Ein anderes Bild ergab sich für den Tribus Exechiini. Weder die Analysen der molekularen Daten alleine noch in Kombination mit den morphologischen Daten ergaben für die einebezogenen Gattungen zweifelsfreie phylogenetische Verwandschaftsbeziehungen mit hoher statistischer Unterstützung. [source] A molecular phylogenetic framework for the evolution of parasitic strategies in cymothoid isopods (Crustacea)JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 1 2008V. Ketmaier Abstract The parasitic isopods belonging to the family Cymothoidae attach under the scales, in the gills or on the tongue of their fish hosts, exhibiting distinctive life-histories and morphological modifications. According to conventional views, the three parasitic types (scale-, gill-, and mouth-dwellers) correspond to three distinct lineages. In this study, we have used fragments of two mitochondrial genes (large ribosomal DNA subunit, 16S rRNA, and cytochrome oxidase I) and two species for each of the three parasitic habits to present a preliminary hypothesis on the evolutionary history of the family. Our molecular data support the monophyly of the family but suggest that , contrary to what was previously believed , the more specialized mouth- and gill-inhabiting species are not necessarily derived from scale-dwelling ones. Zusammenfassung Die parasitischen Isopoden aus der Familie der Cymothoidae heften sich an die Schuppen, Kiemen oder an die Zunge ihrer Fischwirte; dabei zeigen sie unterschiedlichen Lebenszyklen und morphologische Besonderheiten. Bisherigen Untersuchungen zufolge gehören die drei Parasitentypen (Schuppen-, Kiemen- und Mundparasiten) zu drei unterschiedlichen phylogenetischen Linien. In der vorliegenden Untersuchung haben wir Fragmente von zwei mitochondrialen Genen (die gro,e ribosomale DNA - Untereinheit, 16s rRNA und Cytochrome Oxidase I, COI) von je zwei Vertretern der drei Parasitentypen untersucht, um eine vorläufige Hypothese über die evolutionären Beziehungen innerhalb der Familie aufzustellen. Unsere molekularbiologischen Ergebnisse unterstützen die Monophylie dieser Familie. Sie unterstützen jedoch nicht die bisherige Annahme, dass die stärker spezialisierten maul- und kiemenparasitierenden Arten von den schuppenparasitierenden Arten abstammen. [source] Phylogenetic inference regarding Parergodrilidae and Hrabeiella periglandulata (,Polychaeta', Annelida) based on 18S rDNA, 28S rDNA and COI sequencesJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 4 2004J. Jördens Abstract Parergodrilidae and Hrabeiella periglandulata are Annelida showing different combinations of clitellate-like and aclitellate characters. Similarities between both of these taxa and Clitellata have widely been regarded as the result of convergent evolution due to similar selection pressures. The position of the three taxa in the phylogenetic system of Annelida is still in debate. However, in analyses based on 18S rDNA sequences a close relationship of Parergodrilidae with Orbiniidae and Questidae was suggested. To infer their phylogeny the sequences of the 28S rDNA and of the cytochrome oxidase I (COI) gene of Stygocapitella subterranea, Parergodrilus heideri and H. periglandulata were determined. The data were extended by sequences of various species including species from Clitellata and Orbiniidae. Prior to tree reconstruction the dataset was analysed in detail for phylogenetic content by applying a sliding window analysis, a likelihood mapping and Modeltest V.3.04. Subsequently, generalized parsimony and maximum likelihood methods were employed. Clade robustness was estimated by bootstrapping. In addition, combined analyses of the sequences of 18S rDNA and 28S rDNA as well as of 18S rDNA, 28S rDNA and COI were performed. The combination of the data of the two structure genes and a mitochondrial gene improved the resolution obtained with the single datasets slightly. These analyses support a close relationship of Parergodrilidae and Orbiniidae but cannot resolve the position of H. periglandulata. In every analysis Clitellata cluster within ,Polychaeta', confirming previous investigations. Zusammenfassung Die Parergodrilidae und Hrabeiella periglandulata sind Annelida, die unterschiedliche Kombinationen von Clitellaten- und Nicht-Clitellaten-Merkmalen aufweisen. Die Übereinstimmungen zwischen Parergodrilidae, H. periglandulata und Clitellata sind jedoch meistens als Ergebnis konvergenter Evolution auf Grund ähnlicher Selektionsdrücke gedeutet worden. Die Stellung der drei Taxa im phylogenetischen System der Annelida ist noch immer in Diskussion. Analysen, die auf 18S rDNA Sequenzen basieren, weisen jedoch auf eine wahrscheinliche engere Verwandtschaft der Parergodrilidae mit den Orbiniidae und Questidae hin. Um die Phylogenie dieser Taxa aufzuklären, wurden die Sequenzen der 28S rDNA und des COI Gens von Stygocapitella subterranea, P. heideri and H. periglandulata bestimmt. Die Daten wurden durch Sequenzen verschiedener weiterer Arten erweitert, die auch Arten der Clitellata und Orbiniidae umfassen. Vor der phylogenetischen Rekonstruktion wurde der Datensatz im Detail auf das enthaltene phylogenetische Signal durch eine Sliding Window Analyse, ein Likelihood Mapping und Modeltest V.3.04 getestet. Anschließend wurden generalisierte Parsimonie und Maximum Likelihood Methoden angewendet. Die Robustheit der Bäume wurde durch Parsimonie-Bootstrapping abgeschätzt. Zusätzlich wurden kombinierte Analysen der Sequenzen von 18S rDNA und 28S rDNA als auch von 18S rDNA, 28S rDNA und COI durchgeführt. Die Kombination der Daten der beiden Strukturgene und eines mitochondrialen Gens verbesserten geringfügig die Auflösung verglichen mit den Einzelanalysen. Diese Analysen unterstützen eine nahe Verwandtschaft der Parergodrilidae mit den Orbiniidae aber die Stellung von H. periglandulata kann nicht angegeben werden. In jeder Analyse bilden die Clitellata ein Cluster innerhalb der ,Polychaeta', eine Bestätigung früherer Untersuchungen. [source] The genus Adriohydrobia (Hydrobiidae: Gastropoda): polytypic species or polymorphic populations?JOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 4 2001T. Wilke In molluscs, the shell characters have historically played an important role in discrimination among species. However, because of the paucity, variability and degree of homoplasy of shell characters, their sole use for taxonomic and systematic studies is controversial in many groups. In the present paper the genus AdriohydrobiaRadoman, 1973 is used as a paradigm to test relationships of taxa that were considered to be species, mainly on the basis of the shell size variations. We tested whether the genus consists of several sympatric and polytypic species or a single species with polymorphic populations and whether the reported shell size differences, on which the description of three putative species is mainly based, are intrinsic or extrinsic. A fragment of the mitochondrial cytochrome oxidase I (COI) gene was used as an independent genetic marker. We found very little genetic variability in 40 specimens from four populations studied. The nucleotide-sequence diversity (,) within populations ranges from 0.0017 to 0.0056 and the nucleotide-sequence divergence (Dxy) between populations from 0.0018 to 0.0051. The phylogenetic network is very compact with two ,groups' of haplotypes that are separated by only two nucleotide positions. A plot of pairwise nucleotide differences against pairwise shell size differences did not reveal any distinct clusters and a Mantel test did not show any significant associations between the two matrices. Based on the very low genetic diversity, the lack of distinct clusters in the phylogenetic network and the lack of concordance between morphological and genetic differentiation it is concluded that only one species is involved, Adriohydrobia gagatinella. The previously reported morphogroups within Adriohydrobia are probably due to a discrete age structure in these population and/or due to the effect of trematode-induced gigantism. The observed genetic patterns in Adriohydrobia indicate a rapid population growth from an ancestral population of small evolutionary-effective size. The present study stresses the importance of testing species-level hypotheses based on shell characters using one or more independent markers. Die Gattung Adriohydrobia (Hydrobiidae: Gastropoda): polytypische Arten oder polymorphe Populationen? Schalenmerkmale spielen historisch eine wichtige Rolle bei der Bestimmung von Molluskenarten. Die alleinige Nutzung von Schalenmerkmalen für systematische und taxonomische Arbeiten ist jedoch in vielen Gruppen umstritten, da die relativ wenigen Schalenmerkmale oft sehr variabel und durch einen hohen Grad von Homoplasie gekennzeichnet sind. In der vorliegenden Arbeit wurde die Gattung AdriohydrobiaRadoman, 1973 als Fallbeispiel genutzt, um Beziehungen von Arten innerhalb einer Gattung zu untersuchen, die hauptsächlich anhand ihrer Schalengröße unterschieden werden. Es wurde getestet, ob die Gattung mehrere sympatrische und polytypische Arten oder nur eine Art mit polymorphen Populationen umfasst. Darüber hinaus wurde untersucht, ob die dokumentierten Unterschiede in der Schalenhöhe, auf welchen die Beschreibung der drei potentiellen Arten der Gattung hauptsächlich beruhte, intrinsisch oder extrinsisch sind. Als unabhängiger genetischer Marker wurde ein Fragment des mitochondrialen Gens für Cytochromoxidase I (COI) verwendet. Die untersuchten 40 Individuen von vier Populationen zeichneten sich durch eine nur sehr geringe genetische Variabilität aus. Die Nukleotidsequenz-Diversität (,) innerhalb der Populationen variiert zwischen 0.0017 und 0.0056; die Nukleotidsequenz-Divergenz (Dxy) zwischen den Populationen reicht von 0.0018 bi 0.0051. Das phylogenetische Netzwerk ist sehr kompakt und umfasst zwei ,Gruppen' von Haplotypen, welche durch nur zwei Nukleotidpositionen getrennt sind. Die graphische Darstellung von paarweisen Nukleotid-Differenzen gegen paarweise Gehäusegröße-Differenzen lässt keine diskreten Gruppen erkennen und ein Mantel-Test zeigt keine signifikanten Beziehungen zwischen den Matrices. Aufgrund der geringen genetischen Differenzierung, des Fehlens von diskreten Gruppen im phylogenetischen Netzwerk und des nicht-signifikanten Zusammenhanges von morphologischer and genetischer Differenzierung wird geschlussfolgert, dass nur eine Art involviert ist, Adriohydrobia gagatinella. Die in der Literatur dokumentierten Morpho-Gruppen beruhen vermutlich auf einer diskreten Altersstruktur in diesen Populationen und/oder auf den Auswirkungen von trematoden-induziertem Gigantismus. Die festgestellten genetischen Muster in Adriohydrobia lassen das schnelle Wachstum einer Stammpopulation von geringer evolutionär-effektiver Größe vermuten. Die vorliegende Studie ist ein Beispiel dafür, wie wichtig es sein kann, auf Schalenmerkmale beruhende Arthypothesen mit unabhängigen Markern zu verifizieren. [source] Species identification of Hypoderma affecting domestic and wild ruminants by morphological and molecular characterizationMEDICAL AND VETERINARY ENTOMOLOGY, Issue 3 2003D. Otranto Abstract., Cuticular structures and the sequence of the cytochrome oxidase I gene were compared for Hypoderma bovis (Linnaeus), Hypoderma lineatum (De Villers), Hypoderma actaeon Brauer, Hypoderma diana Brauer and Hypoderma tarandi (Linnaeus) (Diptera, Oestridae). Third-stage larvae of each species were examined by scanning electron microscopy revealing differences among species in the pattern and morphology of spines on the cephalic and thoracic segments, by spine patterns on the tenth abdominal segment, and by morphology of the spiracular plates. The morphological approach was supported by the molecular characterization of the most variable region of the cytochrome oxidase I (COI) gene of these species, which was amplified by polymerase chain reaction and analysed. Amplicons were digested with the unique restriction enzyme, BfaI, providing diagnostic profiles able to simultaneously differentiate all Hypoderma species examined. These findings confirm the utility of morphological characters for differentiating the most common Hypoderma larvae and reconfirm the power of the COI gene for studying insect identification and systematics. [source] The Bassian Isthmus and the major ocean currents of southeast Australia influence the phylogeography and population structure of a southern Australian intertidal barnacle Catomerus polymerus (Darwin)MOLECULAR ECOLOGY, Issue 8 2008KATHERINE L. YORK Abstract Southern Australia is currently divided into three marine biogeographical provinces based on faunal distributions and physical parameters. These regions indicate eastern and western distributions, with an overlap occurring in the Bass Strait in Victoria. However, studies indicate that the boundaries of these provinces vary depending on the species being examined, and in particular on the mode of development employed by that species, be they direct developers or planktonic larvae dispersers. Mitochondrial DNA sequence analysis of the surf barnacle Catomerus polymerus in southern Australia revealed an east,west phylogeographical split involving two highly divergent clades (cytochrome oxidase I 3.5 ± 0.76%, control region 6.7 ± 0.65%), with almost no geographical overlap. Spatial genetic structure was not detected within either clade, indicative of a relatively long-lived planktonic larval phase. Five microsatellite loci indicated that C. polymerus populations exhibit relatively high levels of genetic divergence, and fall into four subregions: eastern Australia, central Victoria, western Victoria and Tasmania, and South Australia. FST values between eastern Australia (from the eastern mitochondrial DNA clade) and the remaining three subregions ranged from 0.038 to 0.159, with other analyses indicating isolation by distance between the subregions of western mitochondrial origin. We suggest that the east,west division is indicative of allopatric divergence resulting from the emergence of the Bassian land-bridge during glacial maxima, preventing gene flow between these two lineages. Subsequently, contemporary ecological conditions, namely the East Australian, Leeuwin, and Zeehan currents and the geographical disjunctions at the Coorong and Ninety Mile Beach are most likely responsible for the four subregions indicated by the microsatellite data. [source] Molecular detection of predation by soil micro-arthropods on nematodesMOLECULAR ECOLOGY, Issue 7 2006D. S. READ Abstract The relative importance of the factors driving change in the population dynamics of nematodes in the soil is almost completely unknown. Top-down control by micro-arthropod predators may have a significant impact on nematode population dynamics. We report experiments showing that mites and Collembola were capable of reducing nematode numbers in the laboratory and were feeding on a targeted nematode species in the field. A PCR-based approach was developed for the detection of predation on three species of slug- and insect-pathogenic nematodes: Phasmarhabditis hermaphrodita, Heterorhabditis megidis and Steinernema feltiae. The collembolan Folsomia candida and the mesostigmatid mite Stratiolaelaps miles were employed as model predators to calibrate post-ingestion prey DNA detection times. Fragments of cytochrome oxidase I (COI) mtDNA were sequenced and species-specific primers were designed, amplifying 154-, 154- and 203-bp fragments for each of the nematode species. Detection times for nematode DNA within the guts of Collembola were longer than in mites, with half-lives (50% of samples testing positive) of 08.75 h and 05.03 h, respectively. F. candida significantly reduced numbers of the nematode H. megidis, with rates of predation of ,0.4 nematode infective juveniles per collembolan per hour over 10 h. Four taxa of field-caught micro-arthropod that had been exposed to the nematode P. hermaphrodita for a period of 12 h were analysed and significant numbers of three taxa tested positive. This is the first application of PCR techniques for the study of nematophagy and the first time these techniques have been used to measure predation on nematodes in the field. [source] Multiple introductions promote range expansion of the mollusc Cyclope neritea (Nassariidae) in France: evidence from mitochondrial sequence dataMOLECULAR ECOLOGY, Issue 6 2006B. SIMON-BOUHET Abstract Since the 1970s, the nassariid gastropod Cyclope neritea has been extending its range north along the French Atlantic coasts from the Iberian Peninsula. This may be due to natural spread because of the recent warming of the northeastern Atlantic. However, human-mediated introductions related to shellfish culture may also be a probable explanation for this sudden range expansion. To examine these two hypotheses, we carried out a comprehensive study based on mitochondrial gene sequences (cytochrome oxidase I) of the five recently colonized French bays as well as 14 populations located in the recognized native range of the species. From a total of 594 individuals, we observed 29 haplotypes to split into three divergent clades. In the native range, we observed a low molecular diversity, strong genetic structure and agreement between geography and gene genealogies. Along the French coasts, we observed the opposite: high genetic diversity and low genetic structure. Our results show that recurrent human-mediated introductions from several geographical areas in the native range may be a source for the French Atlantic populations. However, despite the low dispersal ability of C. neritea, the isolation-by-distance pattern in France suggested that this gastropod may have been present (although unnoticed) on the French Atlantic coasts before the 1970s. As C. neritea shows characteristics of a cryptogenic species, the classification of Atlantic populations as either native or introduced is not straightforward. Cryptogenic species should be studied further to determine the status of new populations close to their recognized native range. [source] Molecular ecology of zebra mussel invasionsMOLECULAR ECOLOGY, Issue 4 2006GEMMA E. MAY Abstract The invasion of the zebra mussel, Dreissena polymorpha, into North American waters has resulted in profound ecological disturbances and large monetary losses. This study examined the invasion history and patterns of genetic diversity among endemic and invading populations of zebra mussels using DNA sequences from the mitochondrial cytochrome oxidase I (COI) gene. Patterns of haplotype frequency indicate that all invasive populations of zebra mussels from North America and Europe originated from the Ponto-Caspian Sea region. The distribution of haplotypes was consistent with invasive populations arising from the Black Sea drainage, but could not exclude the possibility of an origin from the Caspian Sea drainage. Similar haplotype frequencies among North American populations of D. polymorpha suggest colonization by a single founding population. There was no evidence of invasive populations arising from tectonic lakes in Turkey, while lakes in Greece and Macedonia contained only Dreissena stankovici. Populations in Turkey might be members of a sibling species complex of D. polymorpha. Ponto-Caspian derived populations of D. polymorpha (, = 0.0011) and Dreissena bugensis (one haplotype) exhibited low levels of genetic diversity at the COI gene, perhaps as a result of repeated population bottlenecks. In contrast, geographically isolated tectonic lake populations exhibited relatively high levels of genetic diversity (, = 0.0032 to 0.0134). It is possible that the fluctuating environment of the Ponto-Caspian basin facilitated the colonizing habit of invasive populations of D. polymorpha and D. bugensis. Our findings were concordant with the general trend of destructive freshwater invaders in the Great Lakes arising from the Ponto-Caspian Sea basin. [source] Phylogeography and systematics of zebra mussels and related speciesMOLECULAR ECOLOGY, Issue 4 2006GREGORY W. GELEMBIUK Abstract The genus Dreissena includes two widespread and aggressive aquatic invaders, the zebra mussel, Dreissena polymorpha, and the quagga mussel, Dreissena bugensis. This genus evolved in the Ponto-Caspian Sea basin, characterized by dynamic instability over multiple timescales and a unique evolutionary environment that may predispose to invasiveness. The objectives of this study were to gain insights into the demographic history of Dreissena species in their endemic range, to reconstruct intraspecific phylogeographic relationships among populations, and to clarify systematics of the genus, using DNA sequences from the mitochondrial cytochrome oxidase I (COI) gene. We found four deeply diverged clades within this genus, with a basal split that approximately coincided with the Cretaceous,Tertiary boundary. Divergence events within the four base clades were much more recent, corresponding to geographically disjunct sets of populations, which might represent species complexes. Across all taxa, populations of Dreissena shared a common pattern of genetic signatures indicating historical population bottlenecks and expansions. Haplotype diversity was relatively low in Ponto-Caspian drainages relative to more stable tectonic lakes in Greece, Macedonia, and Turkey. The phylogeographic and demographic patterns in the endemic range of Dreissena might have resulted from vicariance events, habitat instability, and the high fecundity and passive dispersal of these organisms. [source] Range expansions in the flightless longhorn cactus beetles, Moneilema gigas and Moneilema armatum, in response to Pleistocene climate changesMOLECULAR ECOLOGY, Issue 4 2005CHRISTOPHER IRWIN SMITH Abstract Pollen cores and plant and animal fossils suggest that global climate changes at the end of the last glacial period caused range expansions in organisms indigenous to the North American desert regions, but this suggestion has rarely been investigated from a population genetic perspective. In order to investigate the impact of Pleistocene climate changes and glacial/interglacial cycling on the distribution and population structure of animals in North American desert communities, biogeographical patterns in the flightless, warm-desert cactus beetles, Moneilema gigas and Moneilema armatum, were examined using mitochondrial DNA (mtDNA) sequence data from the cytochrome oxidase I (COI) gene. Gene tree relationships between haplotypes were inferred using parsimony, maximum-likelihood, and Bayesian analysis. Nested clade analysis and coalescent modelling using the programs mdiv and fluctuate were used to identify demographically independent populations, and to test the hypothesis that Pleistocene climate changes caused recent range expansions in these species. A sign test was used to evaluate the probability of observing concerted population growth across multiple, independent populations. The phylogeographical and nested clade analyses reveal a history of northward expansion in both of these species, as well as a history of past range fragmentation, followed by expansion from refugia. The coalescent analyses provide highly significant evidence for independent range expansions from multiple refugia, but also identify biogeographical patterns that predate the most recent glacial period. The results indicate that widespread desert environments are more ancient than has been suggested in the past. [source] Universal primers and PCR of gut contents to study marine invertebrate dietsMOLECULAR ECOLOGY, Issue 3 2005L. E. BLANKENSHIP Abstract Determining the diets of marine invertebrates by gut content analysis is problematic. Many consumed organisms become unrecognizable once partly digested, while those with hard remains (e.g. diatom skeletons) may bias the analysis. Here, we adapt DNA-based methods similar to those used for microbial diversity surveys as a novel approach to study the diets of macrophagous (the deep-sea amphipods Scopelocheirus schellenbergi and Eurythenes gryllus) and microphagous (the bivalve Lucinoma aequizonata) feeders in the deep sea. Polymerase chain reaction (PCR) in conjunction with ,universal' primers amplified portions of the mitochondrial cytochrome c oxidase I (COI) gene for animals ingested by S. schellenbergi and E. gryllus and the 18S rRNA gene for lesser eukaryotes ingested by L. aequizonata. Amplified sequences were combined with sequences from GenBank to construct phylogenetic trees of ingested organisms. Our analyses indicate that S. schellenbergi, E. gryllus and L. aequizonata diets are considerably more diverse than previously thought, casting new light on the foraging strategies of these species. Finally, we discuss the strengths and weaknesses of this technique and its potential applicability to diet analyses of other invertebrates. [source] Phylogeographical pattern correlates with Pliocene mountain building in the alpine scree weta (Orthoptera, Anostostomatidae)MOLECULAR ECOLOGY, Issue 6 2000S. A. Trewick Abstract Most research on the biological effects of Pleistocene glaciation and refugia has been undertaken in the northern hemisphere and focuses on lowland taxa. Using single-strand conformation polymorphism (SSCP) analysis and sequencing of mitochondrial cytochrome oxidase I, we explored the intraspecific phylogeography of a flightless orthopteran (the alpine scree weta, Deinacrida connectens) that is adapted to the alpine zone of South Island, New Zealand. We found that several mountain ranges and regions had their own reciprocally monophyletic, deeply differentiated lineages. Corrected genetic distance among lineages was 8.4% (Kimura 2-parameter [K2P]) / 13% (GTR + I + ,), whereas within-lineage distances were only 2.8% (K2P) / 3.2% (GTR + I + ,). We propose a model to explain this phylogeographical structure, which links the radiation of D. connectens to Pliocene mountain building, and maintenance of this structure through the combined effects of mountain-top isolation during Pleistocene interglacials and ice barriers to dispersal during glacials. [source] Mitochondrial DNA sequences support allozyme evidence for cryptic radiation of New Zealand Peripatoides (Onychophora)MOLECULAR ECOLOGY, Issue 3 2000S. A. Trewick Abstract A combination of single-strand conformation polymorphism analysis (SSCP) and sequencing were used to survey cytochrome oxidase I (COI) mitochondrial DNA (mtDNA) diversity among New Zealand ovoviviparous Onychophora. Most of the sites and individuals had previously been analysed using allozyme electrophoresis. A total of 157 peripatus collected at 54 sites throughout New Zealand were screened yielding 62 different haplotypes. Comparison of 540-bp COI sequences from Peripatoides revealed mean among-clade genetic distances of up to 11.4% using Kimura 2-parameter (K2P) analysis or 17.5% using general time-reversible (GTR + I + ,) analysis. Phylogenetic analysis revealed eight well-supported clades that were consistent with the allozyme analysis. Five of the six cryptic peripatus species distinguished by allozymes were confirmed by mtDNA analysis. The sixth taxon appeared to be paraphyletic, but genetic and geographical evidence suggested recent speciation. Two additional taxa were evident from the mtDNA data but neither occurred within the areas surveyed using allozymes. Among the peripatus surveyed with both mtDNA and allozymes, only one clear instance of recent introgression was evident, even though several taxa occurred in sympatry. This suggests well-developed mate recognition despite minimal morphological variation and low overall genetic diversity. [source] | ||||||||||||||||||||||||||||