Search results for " evolution."
showing 10 items of 9653 documents
Prediction of harmful variants on mitochondrial genes : Test of habitat-dependent and demographic effects in a euryhaline fish
2017
Both effective population size and life history may influence the efficacy of purifying selection, but it remains unclear if the environment affects the accumulation of weakly deleterious nonsynonymous polymorphisms. We hypothesize that the reduced energetic cost of osmoregulation in brackish water habitat may cause relaxation of selective constraints at mitochondrial oxidative phosphorylation (OXPHOS) genes. To test this hypothesis, we analyzed 57 complete mitochondrial genomes of Pungitius pungitius collected from brackish and freshwater habitats. Based on inter- and intraspecific comparisons, we estimated that 84% and 68% of the nonsynonymous polymorphisms in the freshwater and brackish …
Conceptualizing ecosystem tipping points within a physiological framework
2017
Connecting the nonlinear and often counterintuitive physiological effects of multiple environmental drivers to the emergent impacts on ecosystems is a fundamental challenge. Unfortunately, the disconnect between the way “stressors” (e.g., warming) is considered in organismal (physiological) and ecological (community) contexts continues to hamper progress. Environmental drivers typically elicit biphasic physiological responses, where performance declines at levels above and below some optimum. It is also well understood that species exhibit highly variable response surfaces to these changes so that the optimum level of any environmental driver can vary among interacting species. Thus, specie…
The role of in situ species diversification for the evolution of high vascular plant species diversity in the European Alps—A review and interpretati…
2017
Abstract By harbouring ca. 3500 native vascular plant species in an area of ca. 170 000 km2, the European Alps represent a region of very high species diversity. Using the most recently published flora of the area and phylogenetic literature, I here review which proportion of the endemic flora of the Alps is the result of in situ diversification, i.e., of diversification in the area and (largely) restricted to the area. There exist only very few and mostly species-poor species diversifications in the Alps, accounting for ca. 1.2% of the native and for ca. 9% of the endemic flora of the Alps. In contrast to this, ca. 33% of the endemic species of the Alps belong to lineages widespread in the…
Lymphatic vessels of the dura mater: a new discovery?
2015
Aspelund et al. discover the presence of a lymphatic vessel network in the dura mater of the mouse brain and show that these dural lymphatic vessels are important for the clearance of macromolecules from the brain.
<p><strong>A new genus of Phaneropterinae (Orthoptera: Ensifera: Tettigoniidae) </strong><strong>from Central Africa</stro…
2014
The new genus Pseudoplangia is described for Plangia laminifera Karsch, 1896. Its general aspect is similar to that of the genus Plangia Stal, 1873, but it differs remarkably in the vertex width, in the shape of eyes, that are oval and elongate, in the length of mid femora, that are shorter than pronotum length, in the shape of fore and mid legs that are very much laterally compressed, and in the presence of broad-based spines on the hind tibiae.
Zur Bewertung der Blattdornen vonHalimodendron halodendron (Fabaceae)
1979
Halimodendron halodendron is a spiny shrub of north-western Asia. The spines are formed by the rachises of the paripinnate leaves. After abscission of pinnae the rigid rachises remain for several years. In culture these rachis spines do not develop fully.
Chemical Ecology of Floral Resources in Conservation Biological Control.
2023
Conservation biological control aims to enhance populations of natural enemies of insect pests in crop habitats, typically by intentional provision of flowering plants as food resources. Ideally, these flowering plants should be inherently attractive to natural enemies to ensure that they are frequently visited. We review the chemical ecology of floral resources in a conservation biological control context, with a focus on insect parasitoids. We highlight the role of floral volatiles as semiochemicals that attract parasitoids to the food resources. The discovery that nectar-inhabiting microbes can be hidden players in mediating parasitoid responses to flowering plants has highlighted the co…
Macroscytus raunoi, a new burrower bug species from Papua New Guinea (Hemiptera: Heteroptera: Cydnidae: Cydninae)
2016
Abstract Macroscytus raunoi, a new species of the genus Macroscytus Fieber, 1860, is described from the Morobe Province on the northern coast of Papua New Guinea. The new species is similar in its morphological characters to Australian M. arnhemicus J. A. Lis, 1999. Differences in morphology and male genitalia which enable separation of both species are provided.
Description and phylogenetic relationships of a new species of treefrog of theOsteocephalus buckleyispecies group (Anura: Hylidae)
2020
The Osteocephalus buckleyi species group is widely distributed in primary and secondary forests of the Amazon Basin and Guiana Region. Based on integrative analysis, including morphological and genetic data, we estimate the phylogenetic relationships and species boundaries among populations of the Osteocephalus buckleyi group from the Ecuadorian Amazon, focusing on the O. verruciger-O. cannatellai species complex. Our results uncovered the existence of one confirmed candidate species from Sangay National Park and one unconfirmed candidate species. Here, we describe the new species which is morphologically and ecologically distinct from other Osteocephalus species. The new species is unusual…
A new species of Rhopalosiphum (Hemiptera, Aphididae) on Chusquea tomentosa (Poaceae, Bambusoideae) from Costa Rica
2012
copyright 2012, Los autores y Zookeys. Datos incluidos por Lisela Moreira Carmona, responsable de depósitos del área de Patógenos y Plagas de Plantas (CIBCM-UCR). The new species Rhopalosiphum chusqueae Pérez Hidalgo & Villalobos Muller, is described from apterous viviparous females caught on Chusquea tomentosa in Cerro de la Muerte (Costa Rica). The identity of the species is supported both by the morphological features and by a molecular phylogenetic analysis based on a fragment of the mitochondrial DNA containing the 5’ region of the cytochrome c oxidase 1 (COI) and on the nuclear gene coding for the Elongation factor-1 alpha (EF1α). The taxonomic position of the new species is discussed…