Hélène Arambourou

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Laboratory studies have sometimes failed to detect a relationship between toxic stress and morphological defects in invertebrates. Several hypotheses have been proposed to account for this lack of effect. (1) It was suggested that only a combination of stressful conditions - rather than a single one - would affect the phenotype. (2) Phenotypic defects(More)
In order to be a relevant indicator of exposure towards teratogenic stressors, morphological defects should not be passed on to the next generation. In this study, we compare morphological variations in Chironomids collected from a contaminated river stretch with those of their progeny, reared in uncontaminated sediment under laboratory conditions. We(More)
Deformities and fluctuating asymmetry in chironomid larvae have been proposed as sensitive indicators of biological stress and are commonly used to assess the ecological impact of human activities. In particular, they have been associated in Chironomus riparius, the most commonly used species, with heavy metal and pesticide river pollution. In this study,(More)
While selection is a key mechanism of evolution, our understanding of within-season variation in sexual selection remains limited. Here, we studied within-season sexual selection on two key performance traits, flight speed and flight endurance, and a set of morphological and physiological phenotypic traits in a natural population of the territorial(More)
Two key insights to better assess the ecological impact of global warming have been poorly investigated to date: global warming effects on the integrated life cycle and effects of heat waves. We tested the effect of a simulated mild (25 °C) and severe (30 °C) heat wave experienced during the larval stage on the flight ability of the damselfly Ischnura(More)
Heat waves are generally associated with an increased energy consumption and could thus increase the vulnerability to subsequent pesticide exposure. We investigated the combined effect of a heat wave and subsequent exposure to the pesticide chlorpyrifos in Ischnura elegans damselfly larvae. To assess local thermal adaptation to heat waves, we applied these(More)
The aim of the present study was to assess the potential use of biochemical markers and mentum deformities as indicators of long-term exposure to lead (Pb) in Chironomus riparius larvae. To do this, the authors measured 3 biochemical markers (i.e., malondialdehyde level, metallothionein concentration, and energy reserve content) as well as larval growth and(More)
The effects of environmental contaminants on arthropod embryo stages have been poorly investigated in ecotoxicology. Moreover, many of these tests used hatching success as the sole metric, although it is possible to detect many more subtle effects. After a detailed description of embryogenesis in Gammarus fossarum, the present study reports on the sublethal(More)
During morphogenesis numerous morphogenetic factors ensure the production of a target phenotype. By disrupting these processes, a toxic exposure during this period could cause an increase of phenotypic defects. In the present study, embryos of the freshwater amphipod Gammarus fossarum were exposed throughout the embryogenesis to increasing concentrations of(More)
Despite the increased attention for the effects of pesticides under global warming no studies tested how winter warming affects subsequent sensitivity to pesticides. Winter warming is expected to cause delayed negative effects when it increases metabolic rates and thereby depletes energy reserves. Using a common-garden experiment, we investigated the(More)
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