Feeding on micro-algae in the invasive Ponto-Caspian amphipod Dikerogammarus villosus (Sowinsky, 1894)

Feeding on micro-algae is shown in the invasive Ponto-Caspian amphipod Dikerogammarus villosus. Compared with controls, males, females and juveniles of this species significantly reduced the concentration in suspension of unicellular micro-algae. Juveniles had higher concentrations of algae in the cardiac gut than adults. The presence of these algae in the mid- and hindgut was also recorded. This feeding behaviour was filmed and the mechanisms involved are described and discussed. We comment on the use of the Functional Feeding Group (FFG) concept to classify feeding in amphipods. The role of being a feeding-generalist in aiding the invasion process is also discussed.

Marine micro and macro algal species as biosorbents for heavy metals

This paper reviews some practical aspects of the application of algal biomass for the biosorption of heavy metals from wastewater. The ability of different algal species to remove metals varies with algal group and morphology, with the speciation of specific metals and their competition with others in wastewater, and with environmental or process factors. The scattered literature on the uptake of heavy metals by both living and dead algal biomass - both macroalgae and immobilized microalgae - has been reviewed, and the uptake capacity and efficiency of different species, as well as what is known about the mechanisms of biosorption, are presented. Data on metal uptake have commonly been fitted to equilibrium models, such as the Langmuir and Freundlich isotherm models, and the parameters of these models permit the uptake capacity of different algal species under different process conditions to be compared. Higher uptake capacities have been found for brown algae than for red and green algae. Kelps and fucoids are the most important groups of algae used for biosorption of heavy metals, probably because of their abundant cell wall polysacchrides and extracellular polymers. Another important practical aspect is the possibility of re-using algal biomass in several adsorption/desorption cycles (up to 10 have been used with Sargassum spp), and the influence of morphology and environmental conditions on the re-usability of algal tissue is also considered.

Experimental assessment of oyster transfers as a vector for macroalgal introductions

Introduction of non-indigenous species can alter marine communities and ecosystems. In shellfish farming, transfer of livestock, especially oysters, is a common practice and potentially constitutes a pathway for non-indigenous introductions. Many species of seaweeds are believed to have been accidentally introduced in association with these transfers, but there is little direct evidence.

Temporal patterns of territory settlement and detectability in mated and unmated Nightingales Luscinia megarhynchos

In many bird species the sex ratio of adults is male-biased, which is likely to have consequences for the ecology as well as for the conservation of a species. For example, when some males remain unpaired in a population, there should be strong selection on behavioural traits that enhance pairing success. A surplus of males is also likely to have important implications for the interpretation of breeding bird survey data. In our study population of Nightingales Luscinia megarhynchos, about half of the males stayed unpaired, suggesting that the number of males encountered singing was greater than the number of breeding pairs. Furthermore, the detectability (the probability of encountering a male singing) of mated males was only two-thirds that of unmated males when censused in the morning or late in the breeding season. The relative detectability was more similar early in the season and during the twilight periods before sunrise and after sunset. Males that arrived earlier on the breeding grounds were more successful in attracting a mate than males arriving later. Some of the unmated males deserted their territories and prospected areas up to 4000 m distant, whereas others settled on the study site only late in the season and may actually have changed territories. We suggest that adult sex ratios and the time of the census should be taken into account when interpreting the results of breeding bird surveys.

The impact of newly identified loci on coronary heart disease, stroke and total mortality in the MORGAM prospective cohorts

Recently, genome wide association studies (GWAS) have identified a number of single nucleotide polymorphisms (SNPs) as being associated with coronary heart disease (CHD). We estimated the effect of these SNPs on incident CHD, stroke and total mortality in the prospective cohorts of the MORGAM Project. We studied cohorts from Finland, Sweden, France and Northern Ireland (total N=33,282, including 1,436 incident CHD events and 571 incident stroke events). The lead SNPs at seven loci identified thus far and additional SNPs (in total 42) were genotyped using a case-cohort design.We estimated the effect of the SNPs on disease history at baseline, disease events during follow-up and classic risk factors. Multiple testing was taken into account using false discovery rate (FDR) analysis. SNP rs1333049 on chromosome 9p21.3 was associated with both CHD and stroke (HR5=.20, 95% CI 1.08-1.34 for incident CHD events and 1.15, 0.99-1.34 for incident stroke). SNP rs11670734 (19q12) was associated with total mortality and stroke. SNP rs2146807 (10q11.21) showed some association with the fatality of acute coronary event. SNP rs2943634 (2q36.3) was associated with high density lipoprotein (HDL) cholesterol and SNPs rs599839, rs4970834 (1p13.3) and rs17228212 (15q22.23) were associated with non-HDL cholesterol. SNPs rs2943634 (2q36.3) and rs12525353 (6q25.1) were associated with blood pressure. These findings underline the need for replication studies in prospective settings and confirm the candidacy of several SNPs that may play a role in the etiology of cardiovascular disease.