Search results for "Medical And Health Sciences"
showing 10 items of 33461 documents
Condition-dependent effects of corticosterone on a carotenoid-based begging signal in house sparrows
2008
International audience; Begging is a complex display involving a variety of different visual and auditory signals. Parents are thought to use these signals to adjust their investment in food provisioning. The mechanisms that ensure the honesty of begging displays as indicators of need have been recently investigated. It has been shown that levels of corticosterone (Cort), the hormone released during the stress response, increase during food shortage and are associated with an increased begging rate. In a recent study in house sparrows, although exogenous Cort increased begging rate, parents did not accordingly adjust their provisioning rate. Here, we tested the hypothesis that Cort might af…
Magnitude and direction of parasite‐induced phenotypic alterations: a meta‐analysis in acanthocephalans
2020
Several parasite species have the ability to modify their host's phenotype to their own advantage thereby increasing the probability of transmission from one host to another. This phenomenon of host manipulation is interpreted as the expression of a parasite extended phenotype. Manipulative parasites generally affect multiple phenotypic traits in their hosts, although both the extent and adaptive significance of such multidimensionality in host manipulation is still poorly documented. To review the multidimensionality and magnitude of host manipulation, and to understand the causes of variation in trait value alteration, we performed a phylogenetically corrected meta-analysis, focusing on a…
Dental microwear texture reflects dietary tendencies in extant Lepidosauria despite their limited use of oral food processing
2019
Lepidosauria show a large diversity in dietary adaptations, both among extant and extinct tetrapods. Unlike mammals, Lepidosauria do not engage in sophisticated mastication of their food and most species have continuous tooth replacement, further reducing the wear of individual teeth. However, dietary tendency estimation of extinct lepidosaurs usually rely on tooth shape and body size, which allows only for broad distinction between faunivores and herbivores. Microscopic wear features on teeth have long been successfully applied to reconstruct the diet of mammals and allow for subtle discrimination of feeding strategies and food abrasiveness. Here, we present, to our knowledge, the first de…
Technology generation to dissemination: lessons learned from the tef improvement project
2018
Indigenous crops also known as orphan crops are key contributors to food security, which is becoming increasingly vulnerable with the current trend of population growth and climate change. They have the major advantage that they fit well into the general socio-economic and ecological context of developing world agriculture. However, most indigenous crops did not benefit from the Green Revolution, which dramatically increased the yield of major crops such as wheat and rice. Here, we describe the Tef Improvement Project, which employs both conventional- and molecular-breeding techniques to improve tef—an orphan crop important to the food security in the Horn of Africa, a region of the world w…
Paysandisia archon: Behavior, Ecology, and Communication
2017
This chapter on Paysandisia archon behavior, ecology, and communication is presented in three parts. The first part deals with reproductive behavior and the sex pheromone. In this section, mating behavior is described with a consideration of optimal age and diel periodicity. Early observations have shown that mating can occur a few hours after adult molting, from noon to the beginning of the afternoon, according to timing of emergence. The female is described as flying close to perching males and the pair then fly together before mating. The male exhibits a scratching movement with the mid-legs while the female extrudes the abdominal tips. Putative sex pheromone production is discussed in r…
Drastic Genome Reduction in an Herbivore's Pectinolytic Symbiont.
2017
Pectin, an integral component of the plant cell wall, is a recalcitrant substrate against enzymatic challenges by most animals. In characterizing the source of a leaf beetle’s (Cassida rubiginosa) pectin-degrading phenotype, we demonstrate its dependency on an extracellular bacterium housed in specialized organs connected to the foregut. Despite possessing the smallest genome (0.27 Mb) of any organism not subsisting within a host cell, the symbiont nonetheless retained a functional pectinolytic metabolism targeting the polysaccharide’s two most abundant classes: homogalacturonan and rhamnogalacturonan I. Comparative transcriptomics revealed pectinase expression to be enriched in the symbiot…
Resemblance of a model species and its mimic: Response to Bury and Cichoń
2018
An experimental assessment of reproductive isolation and its consequences for seasonal hybridization dynamics
2018
Suppression of Phyllospheric Microbiota Alters Content of Pharmacologically Relevant Compounds of <i>S. nigra</i> Flowers
2018
Accumulating scientific evidence suggests that medicinal plant-associated microbiota has a significant role in biosynthesis of pharmacologically relevant compounds. Suppression of S. nigra microbiota by an antibiotic treatment leads to a decreased emission of volatile terpenoids from S. nigra flowers and an altered metabolome of a host plant. However, it is not known if suppression of microbiota also affects an abundance of health promoting compounds and pharmacologically relevant properties of S. nigra. The present study reveals, that suppression of phyllospheric microbiota by an antibiotic treatment affects total phenolic content (TPC), anti-radical activity (ARA) and total flavonol conte…
A century after introduction: variability in Cepaea hortensis (Müller, 1774) in Sibiu, central Romania
2019
AbstractThe polymorphic land snail Cepaea hortensis was introduced to the city of Sibiu, central Romania, in the first decade of the 20th century and has spread widely across the city. A total of 97 locations were examined in 2017 across the city to determine the habitat preferences and variation in shell size, shape, colour and banding polymorphism of C. hortensis, and to relate these to the same features in the likely source population from Mannheim, Germany, and the first established population in Sibiu. We found that C. hortensis was largely restricted to sites with some woody vegetation cover and showed a marked preference for abandoned and overgrown private gardens. Mean adult shell s…