Javier Fresneda

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Cave organisms have been used as models for evolution and biogeography, as their reduced above-ground dispersal produces phylogenetic patterns of area distribution that largely match the geological history of mountain ranges and cave habitats. Most current hypotheses assume that subterranean lineages arose recently from surface dwelling, dispersive close(More)
Sexual dimorphism in blood pressure (BP) regulation has been observed both in humans and experimental animals, and estrogens have been shown to contribute to this epidemiological observation. A key enzyme in determining estrogen levels is aromatase cytochrome P450. The aim of this study was to evaluate the role of the gene encoding aromatase, CYP19A1, as an(More)
Research on subterranean organisms has focused on the colonization process and some of the associated phenotypic changes, but little is known on the long-term evolutionary dynamics of subterranean lineages and the origin of some highly specialized complex characters. One of the most extreme modifications is the reduction of the number of larval instars in(More)
For management strategies in the context of global warming, accurate predictions of species response are mandatory. However, to date most predictions are based on niche (bioclimatic) models that usually overlook biotic interactions, behavioral adjustments or adaptive evolution, and assume that species can disperse freely without constraints. The deep(More)
A molecular phylogeny of the species from the Trechus brucki clade (previously Trechus uhagoni group)based on fragments of four mitochondrial genes and one nuclear gene is given. We describe Trechus (Trechus) bouillonisp. n. from the western pre-Pyrenees: Sierras de Urbasa-Andía, Navarra, Spain. The species was collected in mesovoid shallow substratum(More)
A key question in evolutionary biology is the relationship between species traits and their habitats. Caves offer an ideal model to test the adjustment of species to their surrounding temperature, as they provide homogeneous and simple environments. We compared two species living under different thermal conditions within a lineage of Pyrenean beetles highly(More)
Geotrechus sarpedon sp. n., a new species of blind Trechini is described from Arbailles Massif, western Pyrenees, trance. The generic attribution of the new species was challenging as it shares morphological features of both genera Geotrechus Jeannel, 1919 and Aphaenops subgenus Hydraphaenops Jeannel, 1926, confirming their polyphyly, which has been(More)
Aphaobius haraldi sp. n. from the mesovoid shallow substratum (MSS) of the Austrian Alps is described, illustrated, and compared with the closest species of the genus. The new species belongs to the A. kraussi species group, formerly including five species. It can be readily separated from other species of the genus by the large parameres, with an enlarged(More)
In insects, whilst variations in life cycles are common, the basic patterns typical for particular groups remain generally conserved. One of the more extreme modifications is found in some subterranean beetles of the tribe Leptodirini, in which the number of larval instars is reduced from the ancestral three to two and ultimately one, which is not active(More)
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