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Macroevolutionary changes such as variation in habitat use or diet are often associated with convergent, adaptive changes in morphology. However, it is still unclear how small-scale morphological variation at the population level can drive shifts in ecology as observed at a macroevolutionary scale. Here, we address this question by investigating how variation in cranial form and feeding mechanics relate to rapid changes in diet in an insular lizard (Podarcis siculus) after experimental introduction into a new environment. We first quantified differences in the skull shape and jaw muscle architecture between the source and introduced population using three-dimensional geometric morphometrics and dissections. Next, we tested the impact of the observed variation in morphology on the mechanical performance of the masticatory system using computer-based biomechanical simulation techniques. Our results show that small differences in shape, combined with variation in muscle architecture, can result in significant differences in performance allowing access to novel trophic resources. The confrontation of these data with the already described macroevolutionary relationships between cranial form and function in these insular lizards provides insights into how selection can, over relatively short time scales, drive major changes in ecology through its impact on mechanical performance.

An increasing part of new entrants in French agriculture refers to permaculture. Permaculture is a movement which was born in Australia whose central aim is to develop sustainable societies less reliant on fossil energy. To reach that goal, the permaculture literature stresses the central importance of systemic design supported by a wide range of principles. In this paper, we analyse the case of Jerôme, a farmer in Western France whose approach was inspired by permaculture. This work is based on a rich material collected during a 6 hour workshop where Jerôme's story was questioned and discussed by a group of scientists and agriculture practitioners. The objective was to investigate how the theoretical framework of permaculture can be concretely applied to a farm and in which extent such an alternative farm can contribute to a wider local development dynamic. In Jérôme's case, permaculture design let to a diversified agroecosystem where autonomy plays a central role. The farm design was influenced by interactions with actors (consumers, farmers, government) and stimulated a local development dynamics (e.g. creation of short supply chains and activities on other farms, changes in diet). The farm design process hybridised strict initial planning and flexibility along the way. The important need for flexibility in agroecological farming systems deeply rooted locally calls for an adaptation of advisory and political tools to support them.; La permaculture qui promeut l'emploi du design systémique pour concevoir des sociétés durables, inspire un nombre croissant d'installations agricoles néo-paysannes. Le récit d'installation d'un agriculteur dans l'Ouest de la France été discuté lors d'un atelier collectif. L'analyse du matériel collecté montre comment la permaculture peut être appliquée à une installation agricole et participer à une dynamique territoriale. Le design en permaculture s'est traduit dans la conception d'un agroécosystème diversifié où l'autonomie joue un rôle majeur. Il s'est construit à l'aide d'interactions avec différents acteurs et a participé à stimuler une dynamique de développement local qui conforte les choix faits sur la ferme. L'importance de la flexibilité dans le design de systèmes agroécologiques fortement ancrés localement est à prendre en compte dans les outils d'accompagnement et de soutien.

DNA-bewijs wordt op steeds grotere schaal gebruikt. Omdat deskundigen meestal niet op zitting komen om daar uitleg te geven van hun bevindingen, moeten schriftelijke DNA-rapporten zelfstandig, zonder mondelinge toelichting, te begrijpen zijn. Procesdeelnemers interpreteren DNA-rapporten echter regelmatig verkeerd en zij vinden de rapporten soms te kort en te bondig.Uit recent onderzoek, dat in dit artikel wordt beschreven, blijkt dat als meer uitleg wordt gegeven in DNA-rapporten deze beter worden begrepen. Er worden dan minder interpretatiefouten gemaakt en de lezers overschatten hun eigen begrip minder. (Zelf)studie van DNA heeft eveneens een positief effect. Uit het onderzoek blijkt dat het wenselijk is dat bij het tot stand komen van DNA-rapportage op een helderder manier over scenario’s en de vragen aan de deskundige wordt gecommuniceerd dan nu gebeurt. Het artikel geeft de bevindingen van het onderzoek weer en beschrijft oplossingsrichtingen. Het debat over DNA-onderzoek staat daarbij centraal.

Contact: Ann-Katrin.Backlund@keg.lu.seContact: Ann-Katrin.Backlund@keg.lu.se; absent

An acute phase response was previously found in cows at parturition, which might be associated with uterine cytokine release. Five late pregnant cows were implanted with vascular catheters in both the maternal aorta and uterine vein. Blood samples were taken to study temporal relationships between changing plasma levels of proinflammatory cytokines and the periparturient acute phase response following prostaglandin (PG)-induced luteolysis at Day 275 of gestation. The plasma levels of three proinflammatory cytokines, tumor necrosis factor-alpha (TNF-alpha), interleukin-1 (IL-1) and interleukin-6 (IL-6), as well as progesterone (P4), PGFM and serum amyloid A (SAA) were measured every 4 h between PG induction and expulsion of the calf. In the arterial plasma, progesterone levels dropped to baseline levels within 10 h following PG treatment, indicative of complete luteolysis. Contrary to expectations, the uterine vein samples showed lower proinflammatory cytokine levels compared with the maternal aorta values. A classical acute phase response, as assessed by SAA, was observed during the expulsive stage, but not during luteolysis.