نتایج جستجو برای: snail shell
تعداد نتایج: 59827 فیلتر نتایج به سال:
The Deepwater Horizon spill (2010) was the largest marine oil spill in US waters to date and one of the largest worldwide. To examine effects of the oil spill on an important salt marsh species over time, we conducted a meta-analysis on marsh periwinkles Littoraria irrorata using published and unpublished sources spanning more than 5 yr (2010−2015), including newly available Natural Resources D...
The lively debate about speciation currently focuses on the relative importance of factors driving population differentiation. While many studies are increasingly producing results on the importance of selection, little is known about the interaction between drift and selection. Moreover, there is still little knowledge on the spatial-temporal scales at which speciation occurs, that is, arrange...
The frequent co-occurrence of two or more genotypes of the same parasite species in the same individual hosts has often been predicted to select for higher levels of virulence. Thus, if parasites can adjust their level of host exploitation in response to competition for resources, mixed-clone infections should have more profound impacts on the host. Trematode parasites are known to induce a wid...
Autotomy of body parts offers various prey animals immediate benefits of survival in compensation for considerable costs. I found that a land snail Satsuma caliginosa of populations coexisting with a snail-eating snake Pareas iwasakii survived the snake predation by autotomizing its foot, whereas those out of the snake range rarely survived. Regeneration of a lost foot completed in a few weeks ...
The aim of the present study was to determine the toxicity of fluorides on energy metabolism in muscles of the Helix aspersa maxima snail. Qualitative and quantitative analysis of purine compounds was performed in slices of foot from mature snails with high-performance liquid chromatography. Fluoride concentrations were measured using an ion-selective electrode and gas chromatography. The resul...
1. The snail Helix aspersa Müller, is negatively geotropic during the daytime, but positive or indifferent at night. 2. The precision of geotropic orientation is a function of the gravity component acting on the body. 3. The rate of geotropic locomotion is also determined by the gravity component (sine of the angle of inclination). 4. The rate of upward movement is increased 1.51 times at 45 de...
Reconstructing environments around archaeological sites is complicated by past land management practices and regional-scale climate proxies that can be contradictory are often located at a distance from the themselves. Here we explore environmental information fossil snail shells which, even when few in number on an site, may prove invaluable constructing site-specific data. The palaeoecology o...
Ecophenotypes reflect local matches between organisms and their environment, and show plasticity across generations in response to current living conditions. Plastic responses in shell morphology and shell growth have been widely studied in gastropods and are often related to environmental calcium availability, which influences shell biomineralisation. To date, all of these studies have overloo...
The influence of latitude, substrate type, tidal level, and host shell size on trematode species-richness and prevalence were assessed using published data on 255 samples from 54 species of marine intertidal gastropods. The analyses were performed at different levels of statistical independence: among all samples, across snail species, and using phylogenetically independent contrasts. Repeatabi...
Cultivated for its richness in nutrients, tomato culture is demanding fertilizer, especially calcium. Calcium deficiencies and physiological disorders cause serious diseases tomatoes. Blossom end rot (BER), susceptible cultivars, may severe economic losses. The goal of this study to determine the effect three organic calcium sources on growth quality fruit production Egg, snail sea shell powder...
نمودار تعداد نتایج جستجو در هر سال
با کلیک روی نمودار نتایج را به سال انتشار فیلتر کنید