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Regulating Biotechnological Innovation in Europe: The Evolution and Challenges of the European Food Safety Authority
No full textOn-going innovation and internationalisation has made political regulation of biotechnology more and more complex. Technological and scientific information and advice from experts has become an important resource for policymakers in the European Union (EU). Since 2003 the European Food Safety Authority (EFSA) is responsible for conducting a risk assessment on food or feed products containing genetically modified organisms (GMO’s). The European Commission (EC) decides on authorisation on the basis of the scientific advice provided by the independent experts that take a seat in the GMO-panel of EFSA. In this paper I will argue how the particular historical evolution and composition of EFSA can be related to its current contested position. It was the BSE crisis of the 1990s that shaped the context of EFSA's establishment. At the time of this crisis, the EC had difficulties finding accurate and timely scientific information. The committees that advised the EC were accused of being infiltrated by the interests of industry and the national interests of Member States. This criticism put pressure on the existing institutions and on the position of experts therein and triggered institutional reform in the area of food safety. EFSA was created in 2002 as a way to isolate the scientific analysis of food and feed products from political decision making and the interests of industry. An analysis of the functioning of the food-safety authority in the area of GMO-authorisation reveals however that the boundaries between scientific expertise and political decision making are not so clear cut. Experts take an active part in constructing the boundaries between the different realms. It can even be argued that the particular organisational demarcation between science and politics within the authorization procedures of GMO's has, paradoxically, even contributed to the current lack of legitimacy and trust among stakeholders.
Iron addition as a shallow lake restoration measure: impacts on charophyte growth
No full textEutrophication has caused a decline of charophyte species in many shallow lakes in Europe. Even though external inputs of phosphorus are declining, internal loading of P from the sediment seems to delay the recovery of these systems. Iron is a useful chemical binding agent to combat internal phosphorus loading. However, the effects of iron addition on charophytes are not yet known. In this study we experimentally tested the potential toxicity of iron(III)chloride (FeCl3) on two different charophytes, Chara virgata Kützing and Chara globularis Thuiller added at the concentration of 20 g Fe m−2 and 40 g Fe m−2 to the surface water. C. virgata growth was not significantly affected, whereas C. globularis growth significantly decreased with increasing iron concentrations. Nonetheless, biomass of both species increased in all treatments relative to starting conditions. The decrease of C. globularis biomass with high iron additions may have been caused by a drop in pH and alkalinity in combination with iron induced light limitation. Iron addition over a longer time scale, however, will not cause this rapid drop in pH. Therefore, we conclude that adding iron(III)chloride in these amounts to the surface water of a lake can potentially be a useful restoration method.
Opposite differential allocation by males and females of the same species
No full textDifferential allocation (DA)—the adjustment of an individual’s parental investment in relation to its mate’s attractiveness—is increasingly recognized as an important component of sexual selection. However, although DA is expected by both sexes of parents in species with biparental care, DA by males has rarely been investigated. We have previously demonstrated a decrease in the feeding rates of female blue tits Cyanistes caeruleus when their mate’s UV coloration was experimentally reduced (i.e. positive DA). In this study, we used the same experimental protocol in the same population to investigate DA by male blue tits in relation to their female’s UV coloration. Males mated to UV-reduced females had higher feeding rates than those mated to control females (i.e. negative DA). Thus, male and female blue tits display opposite DA for the same component of parental effort (chick provisioning), the first time that this has been reported for any species.
Trade-offs between chemical defence and regrowth capacity in Plantago lanceolata
No full textResistance and tolerance are different strategies of plants to deal with herbivore attack. Since resources are limited and resistance and tolerance serve similar functions for plants, trade-offs between these two strategies have often been postulated. In this study we investigated trade-offs between resistance and one aspect of tolerance, the ability to regrow after defoliation. In order to minimize confounding effects of genetic background and selection history, we used offspring derived from artificial selection lines of ribwort plantain (Plantago lanceolata) that differed in their levels of leaf iridoid glycosides (IGs), allelochemicals that confer resistance to generalist herbivores, to study genetic associations with regrowth ability. We tested whether high-IG plants (1) suffer allocation costs of resistance in terms of reduced shoot and root growth, (2) have reduced regrowth ability (tolerance) after defoliation compared to low-IG plants, and (3) whether such costs are more pronounced under nutrient stress. High-IG plants produced fewer inflorescences and side rosettes than low-IG plants and showed a different biomass allocation pattern, but since neither the vegetative, nor the reproductive biomass differed between the lines, there was no evidence for a cost of IG production in terms of total biomass production under either nutrient condition. High-IG plants also did not suffer a reduced capacity to regrow shoot mass after defoliation. However, after regrowth, root mass of high-IG plants grown under nutrient-poor conditions was significantly lower than that of low-IG plants. This suggests that under these conditions shoot regrowth of high-IG plants comes at a larger expense of root growth than in low-IG plants. We speculate therefore that if there is repeated defoliation, high-IG plants may eventually fail to maintain shoot regrowth capacity and that trade-offs between resistance and tolerance in this system will show up after repeated defoliation events under conditions of low resource availability.
Conceptualizing functional traits and ecological characteristics of methane-oxidizing bacteria as life strategies
No full textMethane-oxidizing bacteria (MOB) possess the ability to use methane for energy generation and growth, thereby, providing a key ecosystem service that is highly relevant to the regulation of the global climate. MOB subgroups have different responses to key environmental controls, reflecting on their functional traits. Their unique features (C1-metabolism, unique lipids, and congruence between the 16S rRNA and pmoA gene phylogeny) have facilitated numerous environmental studies, which in combination with the availability of cultured representatives, yield the most comprehensive ecological picture of any known microbial functional guild. Here, we focus on the broad MOB subgroups (type I and type II MOB), and aim to conceptualize MOB functional traits and observational characteristics derived primarily from these environmental studies to be interpreted as microbial life strategies. We focus on the functional traits, and the conditions under which these traits will render different MOB subgroups a selective advantage. We hypothesize that type I and type II MOB generally have distinct life strategies, enabling them to predominate under different conditions and maintain functionality. The ecological characteristics implicated in their adopted life strategies are discussed, and incorporated into the Competitor-Stress tolerator-Ruderal (C-S-R) functional classification framework as put forward for plant communities. In this context, type I MOB can broadly be classified as competitor-ruderal (C-R) while type II MOB fit more within the stress tolerator categories. Finally, we provide an outlook on MOB applications by exemplifying two approaches where their inferred life strategies could be exploited thereby, putting MOB into the context of microbial resource management.
Chronological objects in demographic research
No full textBackground: Calendar time, age and duration are chronological objects. They represent an instant or a time period. Age and duration are usually expressed in units with varying lengths. The number of days in a month or a year depends on the position on the calendar. The units are also not homogeneous and the structure influences measurement. One solution, common in demography, is to use units that are large enough for the results not to be seriously affected by differences in length and structure. Another approach is to take the idiosyncrasy of calendars into account and to work directly with calendar dates. The technology that enables logical and arithmetic operations on dates is available.
Objective: To illustrate logical and arithmetic operations on dates and conversions between time measurements.
Methods: Software packages include utilities to process dates. I use existing and a few new utilities in R to illustrate operations on dates and conversions between calendar dates and elapsed time since a reference moment or a reference event. Three demographic applications are presented. The first is the impact of preferences for dates and days on demographic indicators. The second is event history analysis with time-varying covariates. The third is microsimulation of life histories in continuous time.
Conclusions: The technology exists to perform operations directly on dates, enabling more precise calculations of duration and elapsed time in demographic analysis. It eliminates the need for (a) approximations and (b) transformations of dates, such as Century Month Code, that are convenient for computing durations but are a barrier to interpretation. Operations on dates, such as the computation of age, should consider time units of varying length.