Sewage effects on the food sources and diet of benthic foraminifera living in oxic sediment: A microcosm experiment

A microcosm experiment was conducted to investigate the effects of sewage-derived particulate organic matter (POM) on the food sources and diets of two species of intertidal benthic foraminifera, Ammonia beccarii and Haynesina germanica, using lipid biomarkers to determine trophic relationships. The lipid content of the sediment and associated micro-organisms was a guide to potential food sources while that of the foraminifera was a guide to what they had actually eaten. Six microcosm tanks were established, with constant salinity, temperature and oxygen content, and each with a thin layer of sediment containing living foraminifera. Three microcosms were used as controls and three were treatments to which the POM from secondary treated sewage was added. Each microcosm was treated as a single replicate (to avoid pseudoreplication). The experiment was run for 38 days. The results showed that the food sources (from the sediment) and the diet of the foraminifera did not significantly differ in the controls or the treatments, but quantities of fatty acids decreased in both the sediment system and the foraminifera over the duration of the experiment. It is concluded that sewage-POM (secondary treatment) does not have a direct effect on the food sources of the foraminifera or their diet. The foraminifera did not feed directly on the sewage-derived POM, nor did the addition of sewage stimulate growth of micro-organisms associated with the sediment system. However, recent field data collected by the authors provides evidence that season plays an important role in foraminiferal response to organic pollution (OP), and microcosm sediment might have been unknowingly collected at a time when foraminifera are now known not to respond to OP, i.e. in summer.     

Wood growth response of Calluna vulgaris (L.) Hull to elevated N deposition and drought

Ring diameters and ring number counts were recorded from Calluna stem cross-sections harvested during an N manipulation experiment. The application of dendrochronological methods permitted accurate ageing of shrubs growing in a heathland of known age. Linear regression analyses demonstrated a highly significant association between increasing levels of N input and stem diameter in both watered and droughted plots (droughted in 1997 only). N inputs were identified as the most significant environmental stressor, appearing to speed ageing vis the Calluna growth cycle. Drought sensitivity was noted in the high N treatment plots (120 kg N ha⁻¹ yr⁻¹) with decreased stem diameters. This may have implications in the response of Calluna growth under current climate change scenarios.     

Spatial variation in the magnitude and functional form of density‐dependent processes on the large skipper butterfly Ochlodes sylvanus

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A dinosaur ichnocoenosis from the middle jurassic of Yorkshire,UK

An assemblage of dinosaur tracks from the undersurface of a sandstone bed in the Saltwick Formation (Middle Jurassic) of Yorkshire shows a range of morphological types, preservational variants and behavioral styles. The tracks are combinations of transmitted prints and underprints and include three distinct trackways. One trackway was made by an animal walking on exposed damp sand, another was left by an animal swimming diagonally across a current and being swept down current, while the third may have been made by an animal either running or pushing off with its feet as it drifted down current. Environmental conditions that existed during the formation of the trackways varied between crevasse splay floods and exposed damp sand. The morphology of the swimming tracks is sufficiently distinctive to warrant the erection of a new ichnogenus and ichnospecies—Characichnos tridactylus. Previously described material from Kansas, Wyoming and New Mexico can be attributed to this new ichnogenus, while specimens from Germany and Utah are only provisionally referred to it. This indicates a known range from Triassic to Cretaceous.     

Can adherence to dietary guidelines address excess caloric intake? An empirical assessment for the UK

The facilitation of healthier dietary choices by consumers is a key element of government strategies to combat the rising incidence of obesity in developed and developing countries. Public health campaigns to promote healthier eating often target compliance with recommended dietary guidelines for consumption of individual nutrients such as fats and added sugars. This paper examines the association between improved compliance with dietary guidelines for individual nutrients and excess calorie intake, the most proximate determinant of obesity risk. We apply quantile regressions and counterfactual decompositions to cross-sectional data from the National Diet and Nutrition Survey (2000–01) to assess how excess calorie consumption patterns in the UK are likely to change with improved compliance with dietary guidelines. We find that the effects of compliance vary significantly across different quantiles of calorie consumption. Our results show that compliance with dietary guidelines for individual nutrients, even if successfully achieved, is likely to be associated with only modest shifts in excess calorie consumption patterns. Consequently, public health campaigns that target compliance with dietary guidelines for specific nutrients in isolation are unlikely to have a significant effect on the obesity risk faced by the population.     

Bipedal browsing adaptations of the unusual Late Eocene–earliest Oligocene tylopod Anoplotherium (Artiodactyla, Mammalia)

The first well-preserved, partial associated skeleton of Anoplotherium latipes , with critical details of tibia, femur, ulna and cervical vertebrae, is described from the UK earliest Oligocene. Anoplotherium and related genera are interpreted as facultatively bipedal, extended-limb, high browsers, based especially on the following: pelvis with flared ilia and long pubic symphysis; medially bowed tibiae shorter than femora; trunk vertebrae enlarging caudally; extensive attachment for supraspinous and deltoid muscles for raising the forelimbs; long muscular tail for balance; and large hind foot processes for attachment of suspensory ligaments. Although overall most like extinct ground sloths among bipedal browsers, Anoplotherium is unique in combining long muscular tail, hooves instead of claws and relatively short forelimbs. Primitive retention of the long tail facilitated an erect stance without need for the long, clawed forelimb support evolved by chalicotheres. Emphasis was instead on strengthening support by the hind-quarters. With only toe-number differences, A. latipes and A. commune may have been sexual dimorphs. The large Anoplotherium species would have been able to browse 2–3 m above the ground with no competition from other contemporaneous European terrestrial mammals. Bipedal browsing is an adaptation previously unrecognized in European Eocene communities.  © 2007 Natural History Museum. Journal compilation © 2007 The Linnean Society of London, Zoological Journal of the Linnean Society , 2007, 151 , 609–659.