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241.
Journal of Insect Conservation - Although diversity and abundance of arthropods have been shown to decline globally, they are underrepresented in nature conservation efforts and policies....  相似文献   
242.
Paternity testing was performed in one social group (S) of rhesus macaques from Cayo Santiago, Puerto Rico. In 11/15 cases, sires could be identified comparing the multilocus DNA profiles of 19 males to those of the corresponding mother/child dyads. All 19 males could be excluded from paternity in the remaining four cases. Decision making was partly based on likelihoods of DNA profiles, and the theoretical model underlying these calculation is described. In a second social group (M), held in captivity, paternity testing was impeded by a deficit of maternal bands and by an increased extent of band sharing of mothers and their infants. Some possible explanations for these findings, including increased homozygosity in group M, are discussed.  相似文献   
243.
Soybean lipoxygenase inhibition by nonsteroidal antiinflammatory drugs   总被引:2,自引:0,他引:2  
Eighteen known nonsteroidal antiinflammatory drugs (NSAID) were tested for their action against soybean lipoxygenase (E.C.1.13.11.12) using linoleic acid as substrate. It was found that the best inhibitors of lipoxygenase were naproxen, BW 755C, indomethacin and isoxicam. Drugs with intermediate potency were meclofenamic acid, phenyl-butazone and benoxaprofen. Other drugs such as ibuprofen and zomepirac were only weakly active in the test.  相似文献   
244.
Epigenetic processes have taken center stage for the investigation of many biological processes, and epigenetic modifications have shown to influence phenotype, morphology and behavioural traits such as stress resistance by affecting gene regulation and expression without altering the underlying genomic sequence. The multiple molecular layers of epigenetics synergistically construct the cell type-specific gene regulatory networks, characterized by a high degree of plasticity and redundancy to create cell-type-specific morphology and function. DNA methylation occurring on the 5′ carbon of cytosines in different genomic sequence contexts is the most studied epigenetic modification. DNA methylation has been shown to provide a molecular record of the exposure to a large variety of environmental factors, which might be persistent through the entire lifetime of an organism and even be passed onto the offspring. Animals might display altered phenotypes mediated by epigenetic modifications depending on the developmental stage or the environmental conditions as well as during evolution. Therefore, the analysis of DNA methylation patterns might allow deciphering previous exposures, explaining ecologically relevant phenotypic diversity and predicting evolutionary trajectories enabling accelerated adaption to changing environmental conditions. Despite the explanatory potential of DNA methylation integrating genetic and environmental factors to shape phenotypic variation and contribute significantly to evolutionary dynamics, studies of DNA methylation are still scarce in the field of ecology. This might be at least partly due to the complexity of DNA methylation analysis and the interpretation of the acquired data. In the current issue of Molecular Ecology Resources, Laine and colleagues (Molecular Ecology Resources, 2022) provide a detailed summary of guidelines and valuable recommendations for researchers in the field of ecology to avoid common pitfalls and perform interpretable genome-wide DNA methylation analyses.  相似文献   
245.
Dee  Shannon  Cuttler  Michael  O’Leary  Michael  Hacker  Jorg  Browne  Nicola 《Coral reefs (Online)》2020,39(6):1525-1534
Coral Reefs - A carbonate budget is a comprehensive measure of reef health and function that focuses on processes that produce and remove carbonate. A key parameter of a carbonate budget is reef...  相似文献   
246.
Numerous birds and mammals use vocal signals to advertise feeding opportunities but often such signals vary with individual and contextual factors. Non-breeding ravens call at food that is difficult to access, resulting in the attraction of nearby conspecifics. Although callers may benefit from group formation in various ways, we recently found substantial individual variation in food calling. We here explored whether this variation can be partly explained by the social dynamics in raven foraging groups, together with already known effects of age class and sex. Specifically, we expected ravens to respond to the presence or absence of affiliates that could act as cooperative partners in the forthcoming feeding event, that is they should call when other ravens were present but they themselves were alone rather than when they were also in company of an affiliation partner. We observed the vocal behaviour of individually marked wild ravens and, simultaneously, categorized their affiliative behaviour with other ravens in the minutes before experimentally controlled feedings. In line with our prediction, individuals were less likely to produce food-associated calls when they were in close contact with an affiliation partner prior to feeding as compared to when they were alone. Furthermore, sex and age class influenced food calling as females called more often than males and younger birds called more often than adult ravens. In conclusion, these results suggest that ravens attempt to find support from a particular cooperative partner by broadly advertise feeding opportunities via food-associated calls, especially when they have low chances in contest competition due to their age and sex. These findings lend further support to the assumption of raven flocks being structured by social relationships and individual birds flexibly controlling their vocal signalling according to the current flock composition.  相似文献   
247.
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