Diel variations in the nutritional physiology of Calanus glacialis from Lat. 78°N in the summer

Calanus glacialis (Jaschnov) from Isfjord, western Spitzbergen, showed no tendency to pronounced diurnal vertical migration or cyclic variations in feeding activity. The samples, taken regularly over a 24-h period and at three different depths in the beginning of August, did however show considerable individual variations in feeding activity. These variations, reflected in the results of gut analyses, were not related to variations in the concentrations of particulate protein, carbohydrate or algal pigments in the water. Analyses of the activities of two digestive enzymes and the electron-transport system (ETS) indicated that those few individuals always present below the photic zone were there temporarily, and showed no signs of slowing down their metabolism. The results suggest that the population of C. glacialis, during the Arctic summer, feeds continuously in the upper water layer, but that intermittent, non-synchronous individual feeding rhythms are the rule.     

Molecular phylogeny and evolution of the pelagic copepod genus Neocalanus (Crustacea: Copepoda)

Portions of the mitochondrial genome (ca. 4 kb), encoding three protein-coding (COI, ND4L, ND6) and two ribosomal RNA (srRNA, lrRNA) genes, were sequenced for all six currently recognized species, plus one form, of the pelagic calanoid copepod genus Neocalanus. In Neocalanus gracilis, the ND6 gene was not found in the sequenced portion of the mitochondrial genome. Unambiguously aligned sequences were subjected to Bayesian, maximum-likelihood, maximum-parsimony, and neighbor-joining analyses using Eucalanus bungii as an outgroup. The resultant tree topologies from these four methods were congruent, robust, and all nodes were supported by high bootstrap values and posterior probabilities of 92–100%. Two tropical and subtropical species (N. gracilis and N. robustior) occupied the most basal position, and a subantarctic (N. tonsus) and three subarctic Pacific species (N. cristatus, N. plumchrus, and N. flemingeri) diverged subsequently. Transequatorial dispersal of the ancestral population during glaciations is suggested for this pattern of speciation, in which sister clades exhibited antitropical distributions. Although the area of ocean is much broader in the subantarctic than the subarctic Pacific, a higher number of species occur in the subarctic Pacific (three) than the subantarctic (one). The possibility that marginal seas, such as Japan Sea and Okhotsk Sea, function as natal areas for the divergence of species is discussed.     

Greenberg dysplasia: first reported case with additional non-skeletal malformations and without consanguinity

The original article to which this Erratum refers was published in Prenatal Diagnosis 20(12) 2000, 1008–1011.     

Microgamete formation and the growth rate of Tintinnopsis beroidea

Microgametes have been detected for a species of Tintinnida for the first time. Apparently this method of sexual reproduction occurs rather infrequently in nature, whereas it is the predominant sexual process in vitro. Culturing conditions and the maintenance medium undoubtedly have a profound influence on microgamete appearance. The rate of division of Tintinnopsis beroidea is related to the degree of sexuality of the cells. Newly isolated cells have a doubling time of 0.8 to 1.1 day at an optimum ratio of food: protozoa. The new cultures have a low incidence of microgamete production.This work was supported by a contract with the U.S. Atomic Energy Commission, reference number NYO-3658-29.     

The role of indicator choice in quantifying the threat of atmospheric ammonia to the ‘Natura 2000’ network

New ‘critical levels’ (CLE) for assessing the effects of atmospheric ammonia on sensitive ecosystems have recently been adopted by the United Nations Economic Commission for Europe (UNECE) of 1 and 3 [2–4] μg NH₃ m^?3 of ambient air (including water vapour), for different species sensitivities and their associated habitats. Based on these values, we examined how indicator choice affects estimates of stock-at-risk in the European ‘Natura 2000’ network.We applied an atmospheric model, FRAME, to estimate surface air concentrations of ammonia at 5 km and 1 km resolution for the UK network of Natura sites, optionally including calibration with the National Ammonia Monitoring Network. As a base indicator, we estimated the overall percentage area of the UK Natura network that exceeded critical level thresholds (‘Area Weighted Indicator’, AWI). We compared this with an alternative approach, estimating the percentage number of Natura sites where the critical level was exceeded (‘Designation Weighted Indicator’, DWI), which we consider more relevant under the terms of the Habitats Directive.Using the AWI (with 1 km calibrated ammonia), we estimate that 11.2%, 1.3% and 0.2% area of the UK Natura network exceeds the critical level values of 1, 2 and 3 μg NH₃ m^?3, respectively. By contrast, using the DWI, the equivalent exceedances are 59.1%, 23.6% and 9.8%. The highest regional exceedance (DWI, critical level 1 μg NH₃ m^?3) was calculated for England (91.9% exceeded), and the lowest for Scotland (24.0% exceeded). High resolution maps show that the larger threat estimated by the DWI approach is explained by (i) an anti-correlation between NH₃ concentration and Natura site area and (ii) the fact that exceedance over part of a Natura site is considered to represent a threat to the integrity of the whole site.     

Cluster formation in liverwort-associated methylobacteria and its implications

Pink-pigmented methylotropic bacteria of the genus Methylobacterium inhabit the surfaces of plant organs. In bryophytes, these methylobacteria enhance cell growth, but the nature of this plant–microbe interaction is largely unknown. In this study, methylobacteria were isolated from the upper surface of the free-living thalli of the liverwort Marchantia polymorpha L. Identification of one strain by 16S ribosomal RNA (rRNA) gene-targeted polymerase chain reaction (PCR) and other data show that these microbes represent an undescribed species of the genus Methylobacterium (Methylobacterium sp.). The growth-promoting activity of these wild-type methylobacteria was tested and compared with that of the type strain Methylobacterium mesophilicum. Both types of methylobacteria stimulated surface expansion of isolated gemmae from Marchantia polymorpha by about 350%. When suspended in water, the liverwort-associated bacteria (Methylobacterium sp.) formed dense clusters of up to 600 cells. In liquid cultures of Methylobacterium mesophilicum, single cells were observed, but no clustering occurred. We suggest that the liverwort-associated methylobacteria are co-evolved symbionts of the plants: Cluster formation may be a behavior that enhances the survival of the epiphytic microbes during periods of drought of these desiccation-tolerant lower plants.     

Regional,seasonal and interspecific variation in <Superscript>15</Superscript>N and <Superscript>13</Superscript>C in sympatric mouse lemurs

Madagascar provides some of the rare examples where two or more primate species of the same genus and with seemingly identical niche requirements occur in sympatry. If congeneric primate species co-occur in other parts of the world, they differ in size in a way that is consistent with Hutchinson’s rule for coexisting species, or they occupy different ecological niches. In some areas of Madagascar, mouse lemurs do not follow these “rules” and thus seem to violate one of the principles of community ecology. In order to understand the mechanisms that allow coexistence of sympatric congeneric species without obvious niche differentiation, we studied food composition of two identical sized omnivorous mouse lemur species, Microcebus griseorufus and M. murinus with the help of stable isotope analyses (δ ¹⁵N and δ ¹³C). The two species are closely related sister species. During the rich season, when food seems abundant, the two species do not differ in their nitrogen isotope composition, indicating that the two species occupy the same trophic level. But they differ in their δ ¹³C values, indicating that M. griseorufus feeds more on C₄ and CAM (Crassulacean-acid-metabolism) plants than M. murinus. During the lean season, M. murinus has lower δ ¹⁵N values, indicating that the two species feed at different trophic levels during times of food shortage. Hybrids between the two species showed intermediate food composition. The results reflect subtle differences in foraging or metabolic adaptations that are difficult to quantify by traditional observations but that represent possibilities to allow coexistence of species.     

Of timelines and timeliness: lessons from Typhoon Haiyan in early disaster response

Typhoon Haiyan struck the Philippines on 8 November 2013 with maximum sustained winds of 235 kilometres per hour, adversely affecting at least 11 million people and displacing some 673,000 in the central regions of the country. The disaster clearly overwhelmed the Philippine government despite its seemingly well‐crafted disaster management plan. Using timelines of different organisations, this paper identifies gaps in the government's response, mainly due to its failure in coordinating and managing relief operations, which adversely affected its effectiveness and efficiency in the delivery of critical goods and services following the disaster. The paper also demonstrates how non‐governmental organisations (NGOs), the United Nations, foreign governments and other organisations provided assistance, mainly through aid niching, to cover the government's shortcomings. The paper recommends a paradigm shift in the government's disaster response by integrating collaborative arrangements between government agencies and NGOs, and giving local governments the lead role, with the national government as support, in disaster planning and response.