7 research outputs found

    Broad-scale patterns of body size in squamate reptiles of Europe and North America

    Full text link
    Aim To document geographical interspecific patterns of body size of European and North American squamate reptile assemblages and explore the relationship between body size patterns and environmental gradients. Location North America and western Europe. Methods We processed distribution maps for native species of squamate reptiles to document interspecific spatial variation of body size at a grain size of 110 x 110 km. We also examined seven environmental variables linked to four hypotheses possibly influencing body size gradients. We used simple and multiple regression, evaluated using information theory, to identify the set of models best supported by the data. Results Europe is characterized by clear latitudinal trends in body size, whereas geographical variation in body size in North America is complex. There is a consistent association of mean body size with measures of ambient energy in both regions, although lizards increase in size northwards whereas snakes show the opposite pattern. Our best models accounted for almost 60% of the variation in body size of lizards and snakes within Europe, but the proportions of variance explained in North America were less than 20%. Main conclusions Although body size influences the energy balance of thermoregulating ectotherms, inconsistent biogeographical patterns and contrasting associations with energy in lizards and snakes suggest that no single mechanism can explain variation of reptile body size in the northern temperate zone

    Ryegrass varieties in relation to dairy cattle performance

    No full text

    Butter

    No full text

    Alguns grupos de microrganismos em manteigas vendidas no município de São Paulo Microorganism groups found in butter sold in the City of S. Paulo, Brazil

    Get PDF
    Foram colhidas 105 amostras de manteiga de 5 marcas diferentes vendidas em supermercados da cidade de São Paulo (Brasil) com a finalidade de verificar as condições microbiológicas de manteigas e compará-las com os padrões recomendados. Semanalmente foi colhida uma amostra de cada marca, durante 21 semanas. A partir da parte aquosa de cada amostra, foram realizadas as contagens de bactérias mesófilas e psicrófilas (em ágar padrão e ágar gelisato), coliformes, proteolíticas e de bolores e leveduras e os resultados comparados com alguns parâmetros propostos por vários pesquisadores. Os valores obtidos nas contagens dos vários grupos de microrganismos estudados, em muitos casos podem ser considerados altos, os quais podem ser resultado do processamento e/ou conservação, realizados em condições não satisfatórias.<br>One hundred and five samples of five different brands of butter in the supermarkets of the City of S. Paulo, Brazil were brought in for testing every week for 21 weeks. From the aqueous phase, counts were made for mesophilic and psichrophilic (using the standard plate count, agar and gelysate agar), coliform, proteolytic, and lipolytic bacteria, as well as for yeasts and molds. Results were compared with parameters proposed by several researchers. In many cases, the count values can be considered high, but these high counts may be due to inadequate processing and/or inadequate storage

    Invasive Predators: a synthesis of the past, present, and future

    No full text
    corecore