361 research outputs found

    Hygiene norms across 56 nations are predicted by self-control values and disease threat

    Get PDF
    Three major theories could potentially explain why hygiene norms vary across societies: tightness-looseness theory, disease threat theory, and theory of a civilizing process driven by how self-control is valued. We test these theories using data from a study of 56 countries across the globe, in which almost 20,000 participants reported their norms about spitting in six different contexts, hand washing in six different contexts, and tooth brushing. Participants also reported the perceived tightness of their society, whether they perceived diseases as a threat to their society, and their valuation of self-control. In support of the civilizing process, most of the norms in our study (including most hand washing norms and most spitting norms) were stricter in countries where self-control is valued more highly. A few norms did not follow this main pattern and these norms were instead stricter in countries where disease was perceived as a greater threat. Thus, while the theory of a civilizing process received the strongest support, our data indicate that some combination with the disease threat theory may be required to fully explain country-variation in hygiene norms

    Global sex differences in hygiene norms and their relation to sex equality

    Get PDF
    Strict norms about hygiene may sometimes have health benefits but may also be a burden. Based on research in the United States, it has been suggested that women traditionally shoulder responsibility for hygiene standards and therefore tend to have stricter views on hygiene. However, there is little systematic research on sex differences in hygiene norms at the global scale. We set up two hypotheses: (1) Stricter hygiene norms among women than among men is a global phenomenon. (2) The size of this sex difference varies across nations with the level of sex equality. We examine these hypotheses using data from a recent international survey (N = 17,632). Participants in 56 countries were asked for their views of where it is not appropriate for people to spit and in which situations people should wash their hands. As a measure of sex equality, we use an existing country-level measure of attitudes to equality between the sexes, available for 49 nations in the study. Stricter hygiene norms among women than among men are observed almost everywhere, but there are a few exceptions (most notably Nigeria and Saudi Arabia). The size of the sex difference in hygiene norms varies strongly with the level of sex equality, but in a non-linear way. The sex difference is most pronounced in moderately egalitarian countries with the highest recorded difference being in Chile. In more egalitarian parts of the world, more sex equality is associated with a smaller sex difference in hygiene norms. In the less egalitarian parts of the world, the opposite relation holds. We offer an interpretation in terms of what different levels of sex equality mean for the content of sex roles

    Clutch size in Kittiwakes (Rissa tridactyla) on Lundy

    Get PDF
    Kittiwake (Rissa tridactyla) numbers on Lundy have been in decline for many decades. This decline is monitored using occupied nest counts and productivity data. More recently we have begun collecting data on clutch size at one colony on Lundy. Clutch size is a direct response by a bird to prevailing conditions. Therefore, clutch size data is potentially revealing in terms of what it tells us about Kittiwake response to factors such as food availability and predation risk, in a way that occupied nest counts and productivity data is not. Calculating clutch size is not straightforward for a colonial cliff nesting bird. In this paper we present a pilot study that has calculated clutch size, and then use that data to assess differences in clutch size across the colony with reference to possible differences in predation risk as a function of colony structure. We discuss the limitations of this pilot and also key aspects of the broader ecology, which we believe should also be monitored in order to better understand the plight of this seabird

    Genomic dissection of the 1994 Cronobacter sakazakii outbreak in a French neonatal intensive care unit

    Get PDF
    Background: Cronobacter sakazakii is a member of the genus Cronobacter that has frequently been isolated from powdered infant formula (PIF) and linked with rare but fatal neonatal infections such as meningitis and necrotising enterocolitis. The Cronobacter MLST scheme has reported over 400 sequence types and 42 clonal complexes; however C. sakazakii clonal complex 4 (CC4) has been linked strongly with neonatal infections, especially meningitis. There have been a number of reported Cronobacter outbreaks over the last three decades. The largest outbreak of C. sakazakii was in a neonatal intensive care unit (NICU) in France (1994) that lasted over 3 months and claimed the lives of three neonates. The present study used whole genome sequencing data of 26 isolates obtained from this outbreak to reveal their relatedness. This study is first of its kind to use whole genome sequencing data to analyse a Cronobacter outbreak. Methods: Whole genome sequencing data was generated for 26 C. sakazakii isolates on the Illumina MiSeq platform. The whole genome phylogeny was determined using Mugsy and RaxML. SNP calls were determined using SMALT and SAMtools, and filtered using VCFtools. Results: The whole genome phylogeny suggested 3 distant clusters of C. sakazakii isolates were associated with the outbreak. SNP typing and phylogeny indicate the source of the C. sakazakii could have been from extrinsic contamination of reconstituted infant formula from the NICU environment and personnel. This pool of strains would have contributed to the prolonged duration of the outbreak, which was up to 3 months. Furthermore 3 neonates were co-infected with C. sakazakii from two different genotype clusters. Conclusion: The genomic investigation revealed the outbreak consisted of an heterogeneous population of C. sakazakii isolates. The source of the outbreak was not identified, but probably was due to environmental and personnel reservoirs resulting in extrinsic contamination of the neonatal feeds. It also indicated that C. sakazakii isolates from different genotype clusters have the ability to co-infect neonates

    Draft genome sequence of "Candidatus Cronobacter colletis" NCTC 14934T, a new species in the genus Cronobacter

    Get PDF
    Members of the Cronobacter genus are associated with serious infections in neonates. This is the first report of the draft genome sequence for the newly proposed species Cronobacter colletis

    Draft genome sequences of three newly identified species in the genus Cronobacter, C. helveticus LMG23732T, C. pulveris LMG24059, and C. zurichensis LMG23730T

    Get PDF
    Cronobacter helveticus, Cronobacter pulveris, and Cronobacter zurichensis are newly described species in the Cronobacter genus, which is associated with serious infections of neonates. This is the first report of draft genome sequences for these species

    Draft genome sequence of the earliest Cronobacter sakazakii sequence type 4 strain, NCIMB 8272

    Get PDF
    The Cronobacter sakazakii clonal lineage defined as sequence type 4 (ST4) is associated with severe cases of neonatal meningitis and persistence in powdered infant formula. For genome sequencing of the earliest deposited culture collection strain of Cronobacter sakazakii ST4, we used the strain NCIMB 8272, originally isolated from milk powder in 1950

    Draft genome sequence of a meningitic isolate of Cronobacter sakazakii clonal complex 4, strain 8399

    Get PDF
    The Cronobacter sakazakii clonal lineage defined as clonal complex 4 (CC4), composed of nine sequence types, is associated with severe cases of neonatal meningitis. To date, only closely related C. sakazakii sequence type 4 (ST4) strains have been sequenced. C. sakazakii strain 8399, isolated from a case of neonatal meningitis, was sequenced as the first non-ST4 C. sakazakii strain

    Adult Kittiwake expelling chick from nesting ledge

    Get PDF
    On 17th June 2021, we witnessed an adult Kittiwake Rissa tridactyla expel a chick from its nesting ledge. The chick fell to its death. We made the observation during our annual monitoring of this species on Lundy. A scan of the colony at 12.13 hrs detected unusual movement in a two-chick nest. One chick, which we designated as the beta chick given its smaller size, was unusually positioned outside the nest away from the alpha chick and the adult, which both remained in the nest. We estimate that the beta chick was about 1–2 days old. The site was such that the floor of the ledge extended well behind the nest to a slightly overhanging back wall, and the chick was scrabbling against this back wall. At 12.25 hrs, in a rapid sequence of movements lasting only seconds, the beta chick turned and moved back in the direction of the nest. As it approached, it came between the adult and a side wall and was then grasped in the adult’s beak and expelled in an upward arc, falling into the sea below. No interactions between the alpha and beta were observed

    The niche construction perspective: a critical appraisal

    Get PDF
    Niche construction refers to the activities of organisms that bring about changes in their environments, many of which are evolutionarily and ecologically consequential. Advocates of niche construction theory (NCT) believe that standard evolutionary theory fails to recognize the full importance of niche construction, and consequently propose a novel view of evolution, in which niche construction and its legacy over time (ecological inheritance) are described as evolutionary processes, equivalent in importance to natural selection. Here, we subject NCT to critical evaluation, in the form of a collaboration between one prominent advocate of NCT, and a team of skeptics. We discuss whether niche construction is an evolutionary process, whether NCT obscures or clarifies how natural selection leads to organismal adaptation, and whether niche construction and natural selection are of equivalent explanatory importance.We also consider whether the literature that promotes NCT overstates the significance of niche construction, whether it is internally coherent, and whether it accurately portrays standard evolutionary theory. Our disagreements reflect a wider dispute within evolutionary theory over whether the neo-Darwinian synthesis is in need of reformulation, as well as different usages of some key terms (e.g., evolutionary process)
    • …
    corecore