Genetic Impact of a Severe El Niño Event on Galápagos Marine Iguanas (Amblyrhynchus cristatus)

The El Niño-Southern Oscillation (ENSO) is a major source of climatic disturbance, impacting the dynamics of ecosystems worldwide. Recent models predict that human-generated rises in green-house gas levels will cause an increase in the strength and frequency of El Niño warming events in the next several decades, highlighting the need to understand the potential biological consequences of increased ENSO activity. Studies have focused on the ecological and demographic implications of El Niño in a range of organisms, but there have been few systematic attempts to measure the impact of these processes on genetic diversity in populations. Here, we evaluate whether the 1997–1998 El Niño altered the genetic composition of Galápagos marine iguana populations from eleven islands, some of which experienced mortality rates of up to 90% as a result of El Niño warming. Specifically, we measured the temporal variation in microsatellite allele frequencies and mitochondrial DNA diversity (mtDNA) in samples collected before (1991/1993) and after (2004) the El Niño event. Based on microsatellite data, only one island (Marchena) showed signatures of a genetic bottleneck, where the harmonic mean of the effective population size (Ne) was estimated to be less than 50 individuals during the period between samplings. Substantial decreases in mtDNA variation between time points were observed in populations from just two islands (Marchena and Genovesa). Our results suggests that, for the majority of islands, a single, intense El Niño event did not reduce marine iguana populations to the point where substantial neutral genetic diversity was lost. In the case of Marchena, simultaneous changes to both nuclear and mitochondrial DNA variation may also be the result of a volcanic eruption on the island in 1991. Therefore, studies that seek to evaluate the genetic impact of El Niño must also consider the confounding or potentially synergistic effect of other environmental and biological forces shaping populations

A neo-institutional perspective on ethical decision-making

Drawing on neo-institutional theory, this study aims to discern the poorly understood ethical challenges confronted by senior executives in Indian multinational corporations and identify the strategies that they utilize to overcome them. We conducted in-depth interviews with 40 senior executives in Indian multinational corporations to illustrate these challenges and strategies. By embedding our research in contextually relevant characteristics that embody the Indian environment, we identify several institutional- and managerial-level challenges faced by executives. The institutional-level challenges are interpreted as regulative, normative and cognitive shortcomings. We recommend a concerted effort at the institutional and managerial levels by identifying relevant strategies for ethical decision-making. Moreover, we proffer a multi-level model of ethical decision-making and discuss our theoretical contributions and practical implications

Foot mucus is a good source for non-destructive genetic sampling in polyplacophora

A non-destructive method for collecting samples for DNA analysis from the mucus of molluscs was successfully adapted for use with the genus Ischnochiton. DNA was extracted using a Chelex-based method and the COI subunit of the mtDNA was amplified and sequenced. Sequences from the mucus were crosschecked against sequences from the foot tissue of the same animal and were found to be identical. This method provides a non-destructive way of carrying out larger studies of the genetics of rare organisms and may be of general use for genetic-based field studies of molluscs.<br /

Populations of a cyprinid fish are self-sustaining despite widespread feminization of males

Background: Treated effluents from wastewater treatment works can comprise a large proportion of the flow of rivers in the developed world. Exposure to these effluents, or the steroidal estrogens they contain, feminizes wild male fish and can reduce their reproductive fitness. Long-term experimental exposures have resulted in skewed sex ratios, reproductive failures in breeding colonies, and population collapse. This suggests that environmental estrogens could threaten the sustainability of wild fish populations. Results: Here we tested this hypothesis by examining population genetic structures and effective population sizes (Ne) of wild roach (Rutilus rutilus L.) living in English rivers contaminated with estrogenic effluents. Ne was estimated from DNA microsatellite genotypes using approximate Bayesian computation and sibling assignment methods. We found no significant negative correlation between Ne and the predicted estrogen exposure at 28 sample sites. Furthermore, examination of the population genetic structure of roach in the region showed that some populations have been confined to stretches of river with a high proportion of estrogenic effluent for multiple generations and have survived, apparently without reliance on immigration of fish from less polluted sites. Conclusions: These results demonstrate that roach populations living in some effluent-contaminated river stretches, where feminization is widespread, are self-sustaining. Although we found no evidence to suggest that exposure to estrogenic effluents is a significant driving factor in determining the size of roach breeding populations, a reduction in Ne of up to 65% is still possible for the most contaminated sites because of the wide confidence intervals associated with the statistical model

On analysing the official statistics for antagonistic threats against transports in EU : a supply chain risk perspective

The purpose of this paper is to analysis the risk for antagonistic threats against transports in EU in order to find patterns and trends. The research is based on a system-theoretical approach, which emphasizes a holistic view instead of the characteristics of the different parts. The research method used in this paper is deductive. The analysis is based on official statistics over antagonistic threats against transports in EU within a frame of reference consisting of theories from supply chain risk management and criminology. There is no silver bullet for solving antagonistic threats as it has always been a part of the business. Within this understanding there are many changes in hot spots, modus operandi, theft endangered objects and handling methods during time, but the basic theoretical frame of reference is still more or less the same. The geographically limitation to the EU is done of practical reasons whiles the frame of reference can be used globally for analysis antagonistic threats against transports. This research is limited by the lack of reliable information sources about criminal activities against logistics business. Secondary sources, like official crime statistics, are at best untrustworthy but more likely filled with large parts of hidden statistics. By using several different and independent official statistical sources and analysis the results within a common frame of reference can the validity of the research be secure. The theoretical framework is based on the theory of routine activity and its implications for logistics. This theory explains why the transport network produces the same theft opportunity over and over again