The use of ethical frameworks by students following a new science course for 16-18 year-olds

There has been a move in recent years towards the greater inclusion of social and ethical issues within science courses. This paper examines a new context-based course for 16-18 year-olds (Salters-Nuffield Advanced Biology) who are studying biology in England and Wales. The course is taught through contexts and has an emphasis on social issues and the development of ethical reasoning. Examination of a sample of reports written by students in 2005 as part of the course's summative assessment shows that utilitarian ethical reasoning is used widely and that the other ethical frameworks to which students are introduced in the course – rights and duties, autonomy and virtue ethics – are used substantially less often. In addition, students mostly argue anthropocentrically though many of them argue ecocentrically and/or biocentrically too

Teacher education and the new biology

Recent years have seen a growth not only in biological knowledge but also, and more significantly for teacher education, in the types of knowledge manifested in biology. No longer, therefore, is it adequate for teachers to retain a Mertonian or a Popperian conception of science. Today's teachers of science need also to be able to help their students discuss bioethics and the societal implications of biology, even when these are controversial and contested. Moreover, practical work can no longer be confined to ‘pure’, ‘safe’ and ‘confined’ activities. These are increasingly rejected by students, validly, as boring or irrelevant. Instead, we need to help student undertake a range of activities that help them to develop criticality and the potential for action. While some may see this as an attack on science, I would argue that this attitude is akin to those who once held that religious education (in countries that permit it) should confine itself to ‘the faith’

Teaching evolution in a creationist environment: an approach based on worldviews, not misconceptions

Creationism and intelligent design are becoming more widespread. This article examines the characteristics of religions and the possible relationship between science and religion before going on to consider how science teachers might deal with creationism in their classrooms when teaching evolution. The central argument is that creationism is best seen not as a misconception but as a worldview. The most that a science teacher can normally aspire to is to ensure that students with creationist beliefs understand the scientific position. In the short term, the scientific worldview is unlikely to supplant a creationist one. We can help students to find their science lessons interesting and intellectually challenging without their being threatening. Effective teaching in this area can not only help students learn about the theory of evolution but better to appreciate the way science is done, the procedures by which scientific knowledge accumulates, the limitations of science and the ways in which scientific knowledge differs from other forms of knowledge

Characterization of Sirt2 using conditional RNAi in mice

Within the past eight years, RNA interference (RNAi) has emerged as a powerful experimental tool for gene function analysis in mice. Reversible control of shRNA mediated RNAi has been achieved by using a tetracycline (tet)-inducible promoter. In the presence of the inductor doxycycline (dox), shRNA mediated gene silencing is initiated, whereas RNAi mechanism is blocked in the absence of dox. To achieve spatially and temporally regulated RNAi, the tet inducible system was combined with a Cre/loxP based strategy for tissue specific activation of shRNA constructs. To this end, a loxP-flanked "promoter inhibitory element" (PIE) was placed between the proximal (PSE) and distal sequence element (DSE) of a dox inducible promoter such that promoter function is completely blocked. Re-activation can be achieved through Cre mediated excision of PIE. To allow for gene silencing in a selected tissue, Cre expression can be regulated by a tissue-specific promoter. In mouse ES cells, the system mediated tight regulation of shRNA expression upon Cre mediated activation and dox administration, reaching knockdown efficiencies of >80%. Unexpectedly, the system showed a limited activity in transgenic mice when applied for conditional silencing of two different targets, LacZ and Sirt2. Sirt2 is a member of the sirtuin family which has considerably gained attention in vitro for its possible role in many physiological processes, including adipogenesis and neurodegenerative diseases. To investigate the function of Sirt2 in vivo, the unmodified dox-responsive and tet-inducible promoter was further used for conditional RNAi in transgenic mice. Inducible shRNA expression resulted in efficient silencing of Sirt2 (>90%) in all tissues which have been analyzed. Suppression of Sirt2 during embryogenesis resulted in offspring consisting of equal ratios of wild type and transgenic pups, indicating that Sirt2 is not indispensable for development. In adult animals, glucose metabolism, insulin sensitivity and energy balance appeared to be unaffected by Sirt2 deficiency. Likewise, expression of PPARγ, a downstream target of Sirt2, was not found to be altered upon Sirt2 inhibition. Finally, Sirt2 silencing was induced in an experimental model of Parkinson disease (PD). Data from Rotarod performances to study motor behaviour did not provide any evidence for a role of Sirt2 in PD pathogenesis as suggested by previous in vitro studies. Taken together, conditional Sirt2 silencing in vivo does not support speculation concerning a central role of Sirt2 in physiological processes, embryogenesis and in a mouse model of Parkinson disease

The ethics of genetic research on intelligence

Should research on the possible genetic components of human intelligence be carried out? I first try to provide some general guidelines as to whether any particular piece of research should be undertaken and then consider the specific example of the ethics of genetic research on intelligence. The history of the debate on intelligence does not make one very optimistic that the fruits of such research would be used wisely. However, there are indications that people's understanding of the nature of inheritance may be improving and it could be that such research might have significant benefits. It is worth remembering than the condition phenylketonuria, a genetic disease in any useful sense of the term, and one that leads to mental retardation (i.e. very low intelligence), is now wholly preventable, and indeed very largely prevented, through environmental intervention

Qualitative and quantitative investigations on the macrobenthic fauna of Central Amazon lakes. 1. Lago Tupé, a black water lake on the lower Rio Negro

Lago Tupé is a black water "ria lake". It is connected with the Rio Negro throughout the year and shows similarly large fluctuations in water level, amounting to nearly 8 m in 1971. The exceptionally high minimum water level of the one-year sampling period implied that there was thermal stratification in the lake throughout the year; because of this the oxygen content of the bottom water layers did not exceed 0,6 mg/l, and H2S formed in the hypolimnion during the period of decreasing water level. These unfavourable external conditions led to the development of a qualitatively and, to a lesser extent, quantitatively poor benthic fauna in the lake centre. Dominant were Chaoboridae larvae (192 individuals/m² over the year) and Ostracoda (457 individuals/m² over the year); the Acari were sub-dominant (70 individuals/m² over the year), and Nematoda were also present 110 individuals/m² over the year). The mean annual biomass was 0.136 g/m². The corresponding patterns of abundance and biomass were also determined for the year. The benthic fauna of the littoral zone was investigated during the phases of low and rising water levels, also at a locally fixed sampling station. The characteristic littoral fauna appears only during the low water phase (November to January) when Chironomidae larvae are dominant with an abundance of 43-74 %. The rest of the fauna consists of many groups with low relative abundances. When the water level begins to rise the qualitative composition alters completely within a few weeks, Chaoboridae larvae and Ostracoda becoming dominant. Apart from the absence of Acari the resulting zoocoenose is qualitatively identical with the profundal zoocoenose. It is conceivable that some of the true littoral species migrate at rising water to the neighbouring inundated forest (igapó), and move back again when the water level falls. The rhythmic faunal movements between profundal, littoral and igapô zones, caused by the large water level fluctuations, are schematically represented. Biomass values were also determined in the littoral zone. The values for both this and abundance were much higher than in the lake centre at any given time. The feeding habits of the individual taxa of profundal and littoral zoocoenoses were examined. The Ostracoda are the detritophages of the profundal zoocoenose; they are fed on by the zoophagous Acari and to a certain extent by the chaoborid larvae. In the true littoral zone the phytophages feed on blue green algae and diatoms growing on firm substrates; these are absent from both igapó and profundal zone. The fungi, which are an important food source in the igapó, play a lesser role in the littoral. The larvae of the Tanypodinae are the zoophages of the true Littoral zone. Finally, comparable studies of the zoobenthos of other black water lakes are discussed; these lend support to the inferences from Lago Tupé i.e. the profundal zone of the black water lakes has qualitatively and quantitatively the poorest benthic fauna of all lacustrine biotopes in the Central Amazon