University of Portsmouth

About: University of Portsmouth is a education organization based out in Portsmouth, Portsmouth, United Kingdom. It is known for research contribution in the topics: Population & Galaxy. The organization has 5452 authors who have published 14256 publications receiving 424346 citations. The organization is also known as: Portsmouth and Gosport School of Science and Art & Portsmouth and Gosport School of Science and the Arts.

The effect of growth rate on tissue‐diet isotopic spacing in rapidly growing animals. An experimental study with Atlantic salmon (Salmo salar)

Abstract: The difference in isotopic composition between a consumer’s tissues and that of its diet is a critical aspect of the use of stable isotope analyses in ecological and palaeoecological studies. In a controlled feeding experiment with the Atlantic salmon, Salmo salar, we demonstrate for the first time that the value of tissue-diet isotope spacing in nitrogen in a growing animal is not constant, but varies inversely with growth rate. The value of tissue-diet isotopic spacing in N reflects N use efficiency. Thus, in salmon, growth rate is accompanied by, or requires, increased N use efficiency. The total range in tissue-diet isotopic spacing in N seen in the experimental population of 25 fish was 1%, approximately 50% of the total trophic shift. Mean equilibrium tissue-diet isotopic spacing (� standard deviation) in salmon averaged 2.3% (� 0.3%) and 0.0% (� 0.3%) for N in muscle and liver, respectively, and 2.1% (� 0.1%) and 1.6% (� 0.3%) for C in muscle and liver, respectively. Feeding with a mixed dietary source (wheat and fish-meal origin) resulted in tissue-diet isotopic fractionation in both C and N due to the differential digestibility of food components with distinct isotopic composition. The rate of change in isotopic composition of S. salar tissues was dominated by growth, but the estimated contribution of metabolic turnover to change in tissue N was relatively high for an ectothermic animal at ca. 20–40%. The estimated half-life for metabolic turnover of the tissue N pool was ca. 4 months in both muscle and liver tissue. This is the first study to demonstrate a direct relationship between tissue-diet isotopic spacing in N and growth rate and adds to the growing list of factors known to influence the level of isotopic separation between a consumer’s tissue and that of its diet. Copyright # 2005 John Wiley & Sons, Ltd. Stable isotope analysis (SIA) is commonly used to infer diet and trophic level in ecosystem studies. SIA offers advantages over gut content analysis as a method to study ecosystem structure because the isotopic composition of animal tissue reflects the average diet assimilated over a length of time, usually of the order of weeks to months. SIA may also be performed retrospectively using archived, historic or archaeological materials, 1,2 allowing reconstruction of ecosystem or

How does cognition evolve? Phylogenetic comparative psychology

Abstract: Now more than ever animal studies have the potential to test hypotheses regarding how cognition evolves. Comparative psychologists have developed new techniques to probe the cognitive mechanisms underlying animal behavior, and they have become increasingly skillful at adapting methodologies to test multiple species. Meanwhile, evolutionary biologists have generated quantitative approaches to investigate the phylogenetic distribution and function of phenotypic traits, including cognition. In particular, phylogenetic methods can quantitatively (1) test whether specific cognitive abilities are correlated with life history (e.g., lifespan), morphology (e.g., brain size), or socio-ecological variables (e.g., social system), (2) measure how strongly phylogenetic relatedness predicts the distribution of cognitive skills across species, and (3) estimate the ancestral state of a given cognitive trait using measures of cognitive performance from extant species. Phylogenetic methods can also be used to guide the selection of species comparisons that offer the strongest tests of a priori predictions of cognitive evolutionary hypotheses (i.e., phylogenetic targeting). Here, we explain how an integration of comparative psychology and evolutionary biology will answer a host of questions regarding the phylogenetic distribution and history of cognitive traits, as well as the evolutionary processes that drove their evolution.

Bank profitability and inflation: the case of China

Abstract: Purpose – The purpose of this paper is to evaluate the determinants of bank profitability in China. It examines the effects of inflation on bank profitability, while controlling for comprehensive bank‐specific and industry‐specific variables.Design/methodology/approach – The sample comprises a total of 101 banks (five state‐owned banks, 12 joint‐stock commercial banks and 84 city commercial banks). The period under consideration extends from 2003‐2009. The two step generalized methods of moments (GMM) estimators are applied.Findings – Empirical results exhibit that there is a positive relationship between bank profitability, cost efficiency, banking sector development, stock market development and inflation in China. The authors report that low profitability can be explained by higher volume of non‐traditional activity and higher taxation. Moreover, the authors confirm that there is a competitive environment in the Chinese banking industry. Furthermore, the authors propose policy actions that should be ta...