Browsing by Autor "Philippe Gaubert"

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Characterization of ten polymorphic microsatellite loci in the Andean pupfish Orestias agassizii, with cross-amplification in the sympatric O. luteus
(Springer Science+Business Media, 2010) Yareli Esquer Garrigos; Josie Lambourdière; Carla Ibañez; Philippe Gaubert
Detecting natural hybridization between two vulnerable Andean pupfishes (Orestias agassizii and O. luteus) representative of the Altiplano endemic fisheries
(Springer Science+Business Media, 2015) Yareli Esquer-Garrigos; Bernard Hugueny; Carla Ibañez; Claudia Zepita; Kellie Koerner; Josie Lambourdière; Arnaud Couloux; Philippe Gaubert
Environmental correlates of body size distribution in Cyprinidae (Actinopterygians) depend on phylogenetic scale
(Wiley, 2014) Gaël P.J. Denys; Pablo A. Tedesco; Thierry Oberdorff; Philippe Gaubert
Abstract The pattern of increasing species body size with increasing latitude has been noticed in different groups of animals. Here, we used seven key environmental factors and independent contrasts to assess body size latitudinal clines in Cyprinidae at two phylogenetic levels (inter‐ and intragenera), which were defined using a genus‐level supertree. Model selection procedures revealed that environmental factors shaping body size variation in Cyprinidae differed according to the phylogenetic scale considered. At the higher phylogenetic level, we found that both temperature (negative effect) and habitat availability (positive effect of drainage basin surface area) constituted mechanistic explanations of large‐scale body size distribution. No temperature‐related body size cline was observed at the intragenus level. Instead, competitive interaction (negative effect of species richness), habitat availability (positive effect of drainage basin surface area), migration ability and available energy (positive effects of glacial coverage and actual evapotranspiration) constitute alternative explanations at this lower phylogenetic scale. We conclude that (i) at the intergenus level, cyprinids do show a tendency to be smaller at high temperatures and larger at low temperatures, (ii) this tendency no longer exists at the intragenus level, (iii) latitude per se is a weak predictor of body size clines whatever the taxonomic level analysed, (iv) generalising geographical body size patterns may be rendered difficult by the superimposition of a series of mechanisms across different taxonomic scales, and (v) habitat size, here acting positively at both taxonomic scales, may play a major role in shaping riverine species body size clines.
Non-invasive ancient DNA protocol for fluid-preserved specimens and phylogenetic systematics of the genus <i>Orestias</i> (Teleostei: Cyprinodontidae)
(Q15088586, 2013) Yareli Esquer Garrigos; Bernard Hugueny; Kellie Koerner; Carla Ibañez; Céline Bonillo; Patrice Pruvost; Romain Causse; Corinne Cruaud; Philippe Gaubert
Specimens stored in museum collections represent a crucial source of morphological and genetic information, notably for taxonomically problematic groups and extinct taxa. Although fluid-preserved specimens of groups such as teleosts may constitute an almost infinite source of DNA, few ancient DNA protocols have been applied to such material. In this study, we describe a non-invasive Guanidine-based (GuSCN) ancient DNA extraction protocol adapted to fluid-preserved specimens that we use to re-assess the systematics of the genus Orestias (Cyprinodontidae: Teleostei). The latter regroups pupfishes endemic to the inter-Andean basin that have been considered as a 'species flock', and for which the morphology-based taxonomic delimitations have been hotly debated. We extracted DNA from the type specimens of Orestias kept at the Muséum National d'Histoire Naturelle of Paris, France, including the extinct species O. cuvieri. We then built the first molecular (control region [CR] and rhodopsin [RH]) phylogeny including historical and recently collected representatives of all the Orestias complexes as recognized by Parenti (1984a): agassizii, cuvieri, gilsoni and mulleri. Our ancient DNA extraction protocol was validated after PCR amplification through an approach based on fragment-by-fragment chimera detection. After optimization, we were able to amplify < 200 bp fragments from both mitochondrial and nuclear DNA (CR and RH, respectively) from probably formalin-fixed type specimens bathed entirely in the extraction fluid. Most of the individuals exhibited few modifications of their external structures after GuSCN bath. Our approach combining type material and 'fresh' specimens allowed us to taxonomically delineate four clades recovered from the well-resolved CR tree into four redefined complexes: agassizii (sensu stricto, i.e. excluding luteus-like species), luteus, cuvieri and gilsoni. The mulleri complex is polyphyletic. Our phylogenetic analyses based on both mitochondrial and nuclear DNA revealed a main, deep dichotomy within the genus Orestias, separating the agassizii complex from a clade grouped under shallow dichotomies as (luteus, (cuvieri, gilsoni)). This 'deep and shallow' diversification pattern could fit within a scenario of ancient divergence between the agassizii complex and the rest of Orestias, followed by a recent diversification or adaptive radiation within each complex during the Pleistocene, in- and outside the Lake Titicaca. We could not recover the reciprocal monophyly of any of the 15 species or morphotypes that were considered in our analyses, possibly due to incomplete lineage sorting and/or hybridization events. As a consequence, our results starkly question the delineation of a series of diagnostic characters listed in the literature for Orestias. Although not included in our phylogenetic analysis, the syntype of O. jussiei could not be assigned to the agassizii complex as newly defined. The CR sequence of the extinct O. cuvieri was recovered within the cuvieri clade (same haplotype as one representative of O. pentlandii), so the mtDNA of the former species might still be represented in the wild.