Disparity in the timing of vertebrate diversification events between the northern and southern hemispheres.

ABSTRACT: BACKGROUND: Climatic oscillations throughout the Quaternary had profound effects on temperate biodiversity, but the extent of Quaternary climate change was more severe in temperate regions of the northern hemisphere than in the southern hemisphere. We sought to determine whether this geographic disparity differentially influenced the timing of intraspecific diversification events within ectothermic and endothermic vertebrate species. Using published phylogenetic hypotheses, we gathered data on the oldest intraspecific diversification event within mammal, bird, freshwater fish, amphibian, and reptile species from temperate-zone areas. We then tested whether the timing of diversification events differed between hemispheres. RESULTS: Our analyses provide strong evidence that vertebrates from temperate regions of the northern hemisphere are younger than those from the southern hemisphere. However, we find little evidence to suggest that this relationship differs between endotherms versus ectotherms, or that it varies widely across the five classes of vertebrates that we considered. In addition, we find that on average, endothermic species are much younger than ectothermic species. CONCLUSION: Our findings suggest that geographic variation in the magnitude of climatic oscillations during the Quaternary led to substantial disparity in the timing of intraspecific diversification events between northern and southern hemisphere vertebrates, and that the magnitude of this divergence is largely congruent across vertebrate taxa.

Recent studies on Schistosoma intercalatum: taxonomic status, puzzling distribution and transmission foci revisited

Schistosoma intercalatum, which causes human rectal schistosomiasis in Africa, still presents a great interest for its imprecise taxonomic status and its puzzling distribution in Africa. Two geographically isolated strains of S. intercalatum are recognized, the Lower Guinea strain and the Congo strain, which differ from each other in a number of morphological, biological and biochemical characteristics. Recent molecular data using RAPD markers indicate high divergence between the two strains, with values of Nei and Li's similarity indice allowing recognition of two genetically distinct taxa: experiments on pre- and post-isolating mechanisms are in progress in order to re-evaluate the taxonomic status of this polytypic species. With regard to its geographical distribution, S. intercalatum is characterized by the existence of two stable endemic areas (localized in Lower Guinea and North East of Democratic Republic of Congo) which correspond to the historical areas of species discovery, and the emergence during the last 15 years of new foci of the Lower Guinea strain outside previously known endemic areas. The absence of local adaptation of the Lower Guinea strain to its intermediate host, supported by experimental studies, may help to facilitate the spread of this strain. Nevertheless, the present restricted distribution of this species remains puzzling, because its potential snail hosts (bulinids) are widely distributed throughout much of Africa. Recent experimental and epidemiological studies suggest that interspecific sexual interactions between human schistosomes could have a role in limiting the distribution of S. intercalatum: the competitive sexual processes acting among human schistosomes show that S. haematobium and S. mansoni are always competitively dominant over S. intercalatum. These epidemiological observations lead the authors to distinguish three kinds of transmission foci for S. intercalatum.

Taxes de reincidència 2010 de justícia juvenil: actualització de la taxa de reincidència dels joves sotmesos a mesures de llibertat vigilada i internament en centre

L’estudi actualitza les taxes de reincidència dels menors sotmesos a una mesura d’internament o de llibertat vigilada que van ser publicades a la recerca “La reincidència en el delicte en la justícia de menors” finalitzada l’any 2005 i que van iniciar la sèrie. Aquest estudi ja és el sisè del mateix tipus i, en aquest cas, segueix els joves que van finalitzar una mesura de llibertat vigilada o d’internament l’any 2007, i els segueix fins el 31 de desembre de 2010 amb l’objectiu de saber si han comès un nou delicte que hagi estat detectat per la Xarxa d’execució penal, tant de joves com d’adults. S’ha estudiat tota la població de joves desinternats de centres, que per l’any 2007 foren 213 subjectes. En el cas de llibertat vigilada del total de joves que finalitzaren mesura l’any 2007 (N=886), s’ha fet una mostra de 493 subjectes (interval de confiança:95,5%; marge d’error ±3,04; p=q=50) Els resultats en llibertat vigilada apunten un lleuger augment en la taxa de reincidència (29,6%) respecte l’any anterior. Aquests darrers augments s’expliquen en part per la incorporació al Codi Penal dels delictes de trànsit, on els joves han fet un creixement espectacular que no hi era als anys anteriors. En internament la taxa de reincidència ha tornat a pujar fins el 58,7%. L’estudi permet comparar de forma seriada sis anys d’evolució de la taxa de reincidència juvenil després de la posada en marxa de la Llei Orgànica 5/2000, de 12 de gener, reguladora de la responsabilitat penal dels menors (LORPM).

Eusociality and cooperation

The evolution of eusociality, here defined as the emergence of societies with reproductive division of labour and cooperative brood care, was first seen as a challenge to Darwin's theory of evolution by natural selection. Why should individuals permanently forgo direct reproduction to help other individuals to reproduce? Kin selection, the indirect transmission of genes through relatives, is the key process explaining the evolution of permanently nonreproductive helpers. However, in some taxa helpers delay reproduction until a breeding opportunity becomes available. Overall, eusociality evolved when ecological conditions promote stable associations of related individuals that benefit from jointly exploiting and defending common resources. High levels of cooperation and robust mechanisms of division of labour are found in many animal societies. However, conflicts among individuals are still frequent when group members that are not genetically identical compete over reproduction or resource allocation.

Bats of Borneo: diversity, distributions and representation in protected areas

Protected areas are valuable in conserving tropical biodiversity, but an insufficient understanding of species diversity and distributions makes it difficult to evaluate their effectiveness. This is especially true on Borneo, a species rich island shared by three countries, and is particularly concerning for bats, a poorly known component of mammal diversity that may be highly susceptible to landscape changes. We reviewed the diversity, distributions and conservation status of 54 bat species to determine the representation of these taxa in Borneo's protected areas, and whether these reserves complement each other in terms of bat diversity. Lower and upper bound estimates of bat species composition were characterised in 23 protected areas and the proposed boundaries of the Heart of Borneo conservation area. We used lower and upper bound estimates of species composition. By using actual inventories, species representation was highly irregular, and even if some reserves were included in the Heart of Borneo, the protected area network would still exhibit low complementarity. By inferring species presence from distributions, composition between most reserves was similar, and complementarity was much higher. Predicting species richness using abundance information suggested that bat species representation in reserves may lie between these two extremes. We recommend that researchers better sample biodiversity over the island and address the conservation threats faced in Borneo both within and outside protected areas. While the Heart of Borneo Initiative is commendable, it should not divert attention from other conservation areas.

Glandular areas associated with the male genitalia in Triatoma rubrofasciata (Triatominae, Reduviidae, Hemiptera) and other Reduviidae

In this paper, glandular areas associated with the phallus in Triatoma rubrofasciata are described and illustrated for the first time. The glandular areas lie in the membrane surrounding the articulatory apparatus. In order to unambiguously define the locality of the respective glandular areas, some features of the pygophore-phallus connection are redescribed. A possible functional context of the gland secretions is discussed. A preliminary study of several other Reduviidae implies that the described glandular areas occur in a wider range of taxa in this group.

Variation and evolution of herkogamy in Exochaenium (Gentianaceae): implications for the evolution of distyly.

Backgrounds and Aims The spatial separation of stigmas and anthers (herkogamy) in flowering plants functions to reduce self-pollination and avoid interference between pollen dispersal and receipt. Little is known about the evolutionary relationships among the three main forms of herkogamy - approach, reverse and reciprocal herkogamy (distyly) - or about transitions to and from a non-herkogamous condition. This problem was examined in Exochaenium (Gentianaceae), a genus of African herbs that exhibits considerable variation in floral morphology, including the three forms of herkogamy. Methods Using maximum parsimony and maximum likelihood methods, the evolutionary history of herkogamic and non-herkogamic conditions was reconstructed from a molecular phylogeny of 15 species of Exochaenium and four outgroup taxa, based on three chloroplast regions, the nuclear ribosomal internal transcribed spacer (ITS1 and 2) and the 5·8S gene. Ancestral character states were determined and the reconstructions were used to evaluate competing models for the origin of reciprocal herkogamy. Key results Reciprocal herkogamy originated once in Exochaenium from an ancestor with approach herkogamy. Reverse herkogamy and the non-herkogamic condition homostyly were derived from heterostyly. Distylous species possessed pendent, slightly zygomorphic flowers, and the single transition to reverse herkogamy was associated with the hawkmoth pollination syndrome. Reductions in flower size characterized three of four independent transitions from reciprocal herkogamy to homostyly. Conclusions The results support Lloyd and Webb's model in which distyly originated from an ancestor with approach herkogamy. They also demonstrate the lability of sex organ deployment and implicate pollinators, or their absence, as playing an important role in driving transitions among herkogamic and non-herkogamic conditions.

Effects of sarcoptic mange on the behaviour of the red fox and influence on other fox-born zoonoses in Geneva, Switzerland

Résumé : Une épidémie de gale sarcoptique (Sarcoptes scabiei) touche le canton de Genève depuis 1996. Nous avons étudié l'impact de cette maladie sur différents caractères comportementaux du renard roux (Vulpes vulpes) : l'écologie alimentaire, les comportements spatiaux et l'activité, ainsi que les contacts sociaux. Nous avons également évalué si la gale pouvait influencer la composition et la transmission de la communauté helminthique intestinale du renard. En effet, cette espèce est l'hôte de parasites qui sont liés à des zoonoses importantes, en particulier le ténia échinocoque du renard (Echinococcus multilocularis) pour lequel Genève est considérée comme une zone de haute endémie. Durant 5 années, des carcasses de renards ont été récoltées sur l'ensemble du canton. Nous les avons disséquées et avons conservé différents échantillons pour des analyses ultérieures. Des données sur le poids, l'âge et le statut reproductif des femelles ont ainsi pu être obtenues. Les contenus stomacaux ont été analysés pour déterminer le régime alimentaire, les intestins pour collecter des helminthes, des échantillons de sang pour faire des sérologies et des échantillons de peau pour récupérer les sarcoptes. Des renards sauvages ont également été capturés et équipés de colliers émetteurs afin de déterminer leur activité et leur utilisation de l'espace. Finalement, nous avons réalisé des affûts sur des terriers et des observations nocturnes à l'aide d'un détecteur thermique afin d'étudier les contacts sociaux. Nous avons ensuite considéré tous ces aspects pour comparer les renards galeux aux individus sains. Trois catégories de gale ont été prises en compte selon l'importance de l'infection. L'épidémie a traversé le canton en 8 ans environ et elle a provoqué une forte diminution des populations de renard. Les animaux malades étaient caractérisés par un poids réduit, ils utilisaient des domaines vitaux réduits et présentaient un rythme d'activité irrégulier. En ce qui concerne le régime alimentaire, les renards galeux avaient souvent des estomacs vides ou contenant peu d'aliments d'origine animale. Cette réduction de l'alimentation ne semble pas seulement être liée à des capacités de prédation réduite, mais également à un désintérêt face à la nourriture. Tous les changements de comportement cités étaient plus marqués chez les animaux soumis à une forte infestation. Dix taxons d'helminthes ont été identifiés dans les intestins des renards analysés. Deux d'entre eux représentent un risque de santé publique: Echinococcus multilocularis et Toxocara carvis. Pour ces helminthes, nous n'avons pas identifié de différences de prévalence entre les renards galeux et les animaux sains, mais la charge parasitaire était significativement supérieure chez les individus galeux, en particulier ceux souffrant d'une infestation importante. Ceci est probablement lié à une susceptibilité accrue des individus qui présentent une condition physique amoindrie et des défenses immunitaire affaiblies. Selon nos résultats, nous pouvons conclure que la gale induit des changements comportementaux importants et que ces changements ont une influence potentielle sur la transmission de la gale elle-même, mais également sur la transmission du reste de la communauté parasitaire de l'hôte. Les individus qui souffrent d'une infestation importante sont susceptibles de provoquer une contamination de l'environnement accrue en ce qui concerne des helminthes pouvant provoquer des zoonoses. La gale apparaît être un facteur à ne pas négliger dans le cadre de la gestion de la faune sauvage, mais également en ce qui concerne des problématiques de santé publique. Summary An epidemic outbreak of sarcoptic mange (Sarcoptes scabiei) has struck the canton of Geneva since 1996. The impact of the disease on various behavioural traits of the main host, the red fox (Vulpes vulpes), was investigated: feeding ecology, spatial behaviour and activity, and social contacts. We also evaluated if mange might have an influence on the composition and transmission of the intestinal helminth community of foxes. Indeed, this species is host of parasites with potential zoonotic importance, particularly the fox tapeworm (Echinococcus multilocularis) for which Geneva is reported as endemic area. During 5 years, red fox carcasses have been collected throughout the canton. They were then dissected and various samples conserved for further analysis. Data on weight, age, and reproductive status of females were obtained. Stomach content were analysed for diet analysis, intestines to recover helminths, blood to proceed to ELISAs and skin samples to check for the presence of Sarcoptes mites. Further, wild foxes were captured and fitted with transmitters in order to determine their activity pattern and space use. Finally, we proceeded to direct observations at dens and using a thermal imaging sensor at night to gain information about social contacts. A comparison between healthy and mangy foxes was made for all these aspects. Three categories of mangy foxes were considered from moderately to severely infected. The epidemic wave crossed the canton in about 8 years and induced a significant reduction in fox densities. Mangy individuals appeared to have reduced body weights, to use more restricted home ranges and exhibited an irregular activity pattern. Regarding food, sick foxes often had empty stomachs and consumed less food items of animal origin. The reduction in food intake appeared to be linked not only to a reduced ability to hunt, but also to a reduced interest in food. The changes observed were particularly pronounced in individuals with severe infestation. Ten helminth taxa were recovered from the intestines on the analysed fox carcasses. Two of them have an importance with regard to human public health: Echinococcus multilocularis and Toxocara cams. The prevalence of these helminths did not differ between healthy and mangy foxes, however the worm burden was significantly higher in mangy foxes, particularly those with severe mange. This is probably linked to an increased susceptibility in individuals with a reduced body condition and weakened immune defences. From our observations, we can conclude that mange induces pronounced behavioural changes in the red fox, and that those changes influence the transmission risks of mange itself, but also of the rest of the parasite community of the host. Individuals with severe mange are for example likely to increase the environment contamination of free living stages of helminths with zoonotic importance. Mange appears thus to represent a factor not to be neglected for the management of wild species and for public health issues.

Taxonomic revision of phlebotomine sand fly species in the series davisi and panamensis of the subgenus Psychodopygus Mangabeira, 1941 (Diptera: Psychodidae: Phlebotominae)

Several species of the subgenus Psychodopygus Mangabeira, 1941 are known to be leishmaniosis vectors in Brazil. Some of them are morphologically similar, which makes their identification quite difficult concerning epidemiological studies. The aim of the current work is to study the morphology of adult specimens of the subgenus Psychodopygus, in accordance with the morphological similarity and still taking into account the epidemiological importance of some species. Thus 11 species have been studied, including four subspecies of adult specimens deposited in the phlebotomine collection of Centro de Pesquisas René Rachou-Fiocruz. Morphological characters found in the literature and new features observed in this study were recorded in a taxonomic discussion format. These characters make it easy to separate such species. Four taxa, previously considered as subspecies, were raised to the category of species.

Use of phylogeny to resolve the taxonomy of the widespread and highly polymorphic African giant shrews (Crocidura olivieri group, Crocidurinae, Mammalia).

The aim of this study is to provide a better understanding of the genetic relationships within the widespread and highly polymorphic group of African giant shrews (Crocidura olivieri group). We sequenced 769 base pairs (bp) of the mitochondrial cytochrome b gene and 472 bp of the mitochondrial control region over the entire geographic range from South Africa to Morocco. The analyses reveal four main clades associated with different biomes. The largest clade occurs over a range covering Northwest and Central Africa and includes samples of C. fulvastra, C. olivieri, and C. viaria. The second clade is composed of C. goliath from Gabon, while South African C. flavescens, and C. hirta form two additional clades. On the basis of these results, the validity of some taxa in the C. olivieri group should be re-evaluated.

Confirmation of Anopheles (Anopheles) calderoni Wilkerson, 1991 (Diptera: Culicidae) in Colombia and Ecuador through molecular and morphological correlation with topotypic material

The morphologically similar taxa Anopheles calderoni, Anopheles punctimacula, Anopheles malefactor and Anopheles guarao are commonly misidentified. Isofamilies collected in Valle de Cauca, Colombia, showed morphological characters most similar to An. calderoni, a species which has never previously been reported in Colombia. Although discontinuity of the postsubcostal pale spots on the costa (C) and first radial (R1) wing veins is purportedly diagnostic for An. calderoni, the degree of overlap of the distal postsubcostal spot on C and R1 were variable in Colombian specimens (0.003-0.024). In addition, in 98.2% of larvae, seta 1-X was located off the saddle and seta 3-C had 4-7 branches in 86.7% of specimens examined. Correlation of DNA sequences of the second internal transcribed spacer and mtDNA cytochrome c oxidase subunit I gene (COI) barcodes (658 bp of the COI gene) generated from Colombian progeny material and wild-caught mosquitoes from Ecuador with those from the Peruvian type series of An. calderoni confirmed new country records. DNA barcodes generated for the closely related taxa, An. malefactor and An. punctimacula are also presented for the first time. Examination of museum specimens at the University of the Valle, Colombia, revealed the presence of An. calderoni in inland localities across Colombia and at elevations up to 1113 m.

Phylogeny and circumscription of Sapindaceae revisited: molecular sequence data, morphology and biogeography support recognition of a new family, Xanthoceraceae

Background and aims Recent studies have adopted a broad definition of Sapindaceae that includes taxa traditionally placed in Aceraceae and Hippocastanaceae, achieving monophyly but yielding a family difficult to characterize and for which no obvious morphological synapomorphy exists. This expanded circumscription was necessitated by the finding that the monotypic, temperate Asian genus Xanthoceras, historically placed in Sapindaceae tribe Harpullieae, is basal within the group. Here we seek to clarify the relationships of Xanthoceras based on phylogenetic analyses using a dataset encompassing nearly 3/4 of sapindaceous genera, comparing the results with information from morphology and biogeography, in particular with respect to the other taxa placed in Harpullieae. We then re-examine the appropriateness of maintaining the current broad, morphologically heterogeneous definition of Sapindaceae and explore the advantages of an alternative family circumscription. Methods Using 243 samples representing 104 of the 142 currently recognized genera of Sapindaceae s. lat. (including all in Harpullieae), sequence data were analyzed for nuclear (ITS) and plastid (matK, rpoB, trnD-trnT, trnK-matK, trnL-trnF and trnS-trnG) markers, adopting the methodology of a recent family-wide study, performing single-gene and total evidence analyses based on maximum likelihood (ML) and maximum parsimony (MP) criteria, and applying heuristic searches developed for large datasets, viz, a new strategy implemented in RAxML (for ML) and the parsimony ratchet (for MP). Bootstrap analyses were performed for each method to test for congruence between markers. Key results Our findings support earlier suggestions that Harpullieae are polyphyletic: Xanthoceras is confirmed as sister to all other sampled taxa of Sapindaceae s. lat.; the remaining members belong to three other clades within Sapindaceae s. lat., two of which correspond respectively to the groups traditionally treated as Aceraceae and Hippocastanaceae, together forming a clade sister to the largely tropical Sapindaceae s. str., which is monophyletic and morphologically coherent provided Xanthoceras is excluded. Conclusion To overcome the difficulties of a broadly circumscribed Sapindaceae, we resurrect the historically recognized temperate families Aceraceae and Hippocastanaceae, and describe a new family, Xanthoceraceae, thus adopting a monophyletic and easily characterized circumscription of Sapindaceae nearly identical to that used for over a century.

Molecular divergence in the timeless and cpr genes among three sympatric cryptic species of the Anopheles triannulatus complex

Anopheles triannulatus s.l. is a malaria vector with a wide geographic distribution, ranging from Argentina-Nicaragua and Trinidad. Here we analysed sequences of two genes, timeless and cpr, to assess the genetic variability and divergence among three sympatric cryptic species of this complex from Salobra, central-western Brazil. The timeless gene sequences did not conclusively differentiate Anopheles halophylus and An. triannulatus species "C". However, a partial separation has been observed between these species and An. triannulatus s.s. Importantly, the analysis of the cpr gene sequences revealed fixed differences, no shared polymorphisms and considerable genetic differentiation among the three species of the An. triannulatus complex. The results confirm that An. triannulatus s.s., An. halophylus and An. triannulatus species C are distinct taxa, with the latter two likely representing a more recent speciation event.

The phylogeny of Simulium (Chirostilbia) (Diptera: Simuliidae) and perspectives on the systematics of the genus in the Neotropical Region

Recently, knowledge of Neotropical Simuliidae has been accumulating quickly. However, information about supra-specific relationships is scarce and diagnoses of Simulium subgenera are unsatisfactory. To investigate the relationships among Simulium (Chirostilbia) species and test the subgenus monophyly, we performed a cladistic analysis. The ingroup included all species of this subgenus and the outgroup included representatives of the 17 species groups of Neotropical Simulium and three Holarctic species. The study was based on a data matrix with 31 terminal taxa and 45 morphological characteristics of adult, pupa and larva. The phylogenetic analysis under equal weights resulted in eight most-parsimonious trees (length = 178, consistency index = 34, retention index = 67). The monophyly of the S. (Chirostilbia) was not supported in our analysis. The Simulium subpallidum species group was closer to Simulium (Psilopelmia) and Simulium (Ectemnaspis) than to the Simulium pertinax species group. Additionally, we describe the three-dimensional shape of the terminalia of male and female of Simulium (Chirostilbia) for the first time and provide comments about the taxonomic problems involving some species of the subgenus: Simulium acarayense, Simulium papaveroi, S. pertinax, Simulium serranum, Simulium striginotum and S. subpallidum.

Chromosomal rearrangements and gene flow over time in an inter-specific hybrid zone of the Sorex araneus group.

Most hybrid zones have existed for hundreds or thousands of years but have generally been observed for only a short time period. Studies extending over periods long enough to track evolutionary changes in the zones or assess the ultimate outcome of hybridization are scarce. Here, we describe the evolution over time of the level of genetic isolation between two karyotypically different species of shrews (Sorex araneus and Sorex antinorii) at a hybrid zone located in the Swiss Alps. We first evaluated hybrid zone movement by contrasting patterns of gene flow and changes in cline parameters (centre and width) using 24 microsatellite loci, between two periods separated by 10 years apart. Additionally, we tested the role of chromosomal rearrangements on gene flow by analysing microsatellite loci located on both rearranged and common chromosomes to both species. We did not detect any movement of the hybrid zone during the period analysed, suggesting that the zone is a typical tension zone. However, the gene flow was significantly lower among the rearranged than the common chromosomes for the second period, whereas the difference was only marginally significant for the first period. This further supports the role of chromosomal rearrangements on gene flow between these taxa.