Search results for "POD"
showing 10 items of 1958 documents
2018
BackgroundThe insect cuticle covers the whole body and all appendages and has bi-directionnal selective permeability: it protects against environmental stress and pathogen infection and also helps to reduce water loss. The adult cuticle is often associated with a superficial layer of fatty acid-derived molecules such as waxes and long chain hydrocarbons that prevent rapid dehydration. The waterproofing properties of cuticular hydrocarbons (CHs) depend on their chain length and desaturation number.DrosophilaCH biosynthesis involves an enzymatic pathway including several elongase and desaturase enzymes.MethodsThe link between desiccation resistance and CH profile remains unclear, so we tested…
Hemocyanin genes as indicators of habitat shifts in Panpulmonata?
2018
Hemocyanin is the primary respiratory protein for the majority of the Mollusca and therefore directly interfaces with the physiological requirements of each species and the environments to which they are adapted. Hemocyanin is therefore likely to have been evolutionarily imprinted by significant habitat shifts. In the gastropod clade Panpulmonata (>30,000 species) major realm transitions have occurred multiple times independently and may have contributed to the diversification of this group. Yet, little is known about the adaptive changes linked to these habitat shifts. In order to gain deeper insight into the evolution of panpulmonate hemocyanins and to infer possible impacts associated wi…
Nacre evolution: a proteomic approach.
2009
AbstractFrom an evolutionary viewpoint, the molluscan nacre constitutes a fascinating object. This microstructure appeared early, in the Lower Cambrian period, about 530 million years ago, and since then, has been kept unchanged until today. Nacre is restricted to the conchiferan mollusks, where it occurs in t least three main classes, bivalves, gastropods and cephalopods. The aim of the present study is to investigate whether all nacres are built from the same “macromolecular tools”, proteins of the nacre matrix. To this end, we studied three new nacre models, the freshwater bivalve Unio pictorum, the cephalopod Nautilus macromphalus, and the gastropod Haliotis asinina, to which we applied…
2013
Parasitized individuals are often expected to be poor competitors because they are weakened by infections. Many trematode species, however, although extensively exploiting their mollusc hosts, also induce gigantism (increased host size) by diverting host resources towards growth instead of reproduction. In such systems, alternatively to reduced competitive ability due to negative effects of parasitism on host performance, larger size could allow more efficient resource acquisition and thus increase the relative competitive ability of host individuals. We addressed this hypothesis by testing the effect of a trematode parasite Diplostomum pseudospathaceum on the competitive ability of its sna…
Phylogeography of two cryptic species of African desert jerboas (Dipodidae: Jaculus)
2012
The lesser Egyptian jerboa Jaculus jaculus is a desert dwelling rodent that inhabits a broad Arabian–Saharan arid zone. Recently, two distant sympatric lineages were described in North-West Africa, based on morphometric and molecular data, which may correspond to two cryptic species. In the current study, phylogenetic relationships and phylogeographical structure among those lineages and geographical populations from North Africa and the Middle East were investigated. The phylogeographical patterns and genetic diversity of the cytochrome b gene (1110 bp) were addressed on 111 jerboas from 41 localities. We found that the variation in Africa is partitioned into two divergent mitochondrial cl…
Chenopodium album L. (Fat Hen): In Vitro Cell Culture, and Production of Secondary Metabolites (Phytosterols and Ecdysteroids)
1998
The name Chenopodium is derived from the Greek words chenos (goose) and podos (foot), because the leaves often resemble goose feet. This genus consists of ca. 120 species, widely distributed over the world, 45 of which have been described in India.
Collapse of the endemic lizard Podarcis pityusensis on the island of Ibiza mediated by an invasive snake
2021
Abstract The invasive snake Hemorrhois hippocrepis colonized the island of Ibiza (Balearic Islands) in 2003 as stowaways inside trunks of olive trees imported for gardening. It has quickly spread since 2010, posing a threat to the island’s only remaining endemic vertebrate, the Ibiza wall lizard Podarcis pityusensis. We map the yearly expansion rate of the snake and estimate via transect surveys how severely it affects the distribution and abundance of the endemic lizard. As well, we surveyed 9 of 30 small lizard populations on islets surrounding Ibiza that have been isolated since the Last Glacial Maximum. Snakes had invaded 49% of Ibiza’s land area by 2018, and censuses show a critical co…
2021
Abstract The Mediterranean Basin has experienced extensive change in geology and climate over the past six million years. Yet, the relative importance of key geological events for the distribution and genetic structure of the Mediterranean fauna remains poorly understood. Here, we use population genomic and phylogenomic analyses to establish the evolutionary history and genetic structure of common wall lizards (Podarcis muralis). This species is particularly informative because, in contrast to other Mediterranean lizards, it is widespread across the Iberian, Italian, and Balkan Peninsulas, and in extra-Mediterranean regions. We found strong support for six major lineages within P. muralis, …
Do colour morphs of wall lizards express different personalities?
2021
Abstract Colour morphs sometimes have different behavioural strategies which may be maintained by frequency or density dependence mechanisms. We investigated temporal changes in behavioural reaction to a novel environment among colour morphs (yellow, orange, white) of the European wall lizard (Podarcis muralis). Adult males were given two 15 min experimental trials, and their locomotion was highly consistent between the two trials. Boldness, freezing and escape behaviour were less repeatable. Colour morphs differed in their locomotion and freezing behaviour. Boldness was similar among the morphs, whereas escape behaviour was lowest in yellow morph. Consequently, yellow morph males tended to…
Absorption, translocation and metabolism of pyridate in a tolerant crop (Zea mays) and two susceptible weeds (Polygonum lapathifolium L. and Chenopod…
1988
Summary Absorption, translocation and metabolism of 14C-pyridate were compared in tolerant maize. moderately susceptible Polygonum lapathifolium and susceptible Chenopodium album. Foliar absorption was limited in all species, but comparatively higher penetration levels were observed in younger leaves of dicotyledonous species. The absorbed radioactivity was not very mobile and translocation appeared mainly sym-plastic. Herbicide selectivity could not be explained on the basis of absorption and transport. Chenopodium and P. lapathifolium degraded pyridate and formed unstable water-soluble conjugates that easily released a phytotoxic metabolite. By contrast, more stable unidentified water-sol…