Search results for "Dam"

Pesticide-induced changes in personality depend on the urbanization level

2017

Globally increasing urbanization causes major anthropogenic changes in ecosystems, drastically altering phenotypes of organisms. Increased contamination is a well-known result of urbanization, and its effect on behaviour has been extensively studied. Yet, animal personality, consistent behavioural variation between individuals, has rarely been investigated in the context of anthropogenic contaminants. Changes in personalities may affect the viability of populations, and even alter community dynamics. We investigated the effects of exposure to a sublethal dose of the commonly used pesticide esfenvalerate on two personality traits, activity and boldness, and compared these effects between rep…

Do allopatric maleCalopteryx virgodamselflies learn species recognition?

2012

There is a growing amount of empirical evidence that premating reproductive isolation of two closely related species can be reinforced by natural selection arising from avoidance of maladaptive hybridization. However, as an alternative for this popular reinforcement theory, it has been suggested that learning to prefer conspecifics or to discriminate heterospecifics could cause a similar pattern of reinforced premating isolation, but this possibility is much less studied. Here, we report results of a field experiment in which we examined (i) whether allopatric Calopteryx virgo damselfly males that have not encountered heterospecific females of the congener C. splendens initially show discri…

Mechanisms of Defence to Pathogens : Biochemistry and Physiology

2014

SPE IPM; International audience; Plant defences comprise both pre-existing barriers as well as defences induced upon perception of pathogen-associated molecular patterns (PAMPs) or microbe-associated molecular patterns (MAMPs) or molecules produced from damage as a result of infection (damage-associated molecular patterns (DAMPs)). This chapter focuses on the induced mechanisms of defence. The inducibility of phytoalexin biosynthesis has probably been favoured in the course of evolution by biological constraints such as metabolic costs and functional side-effects associated with chemical defence. Historically, the term ‘hypersensitive’ refers to the rapid and localized cell death induced in…

Interactions between Climate Change and Infrastructure Projects in Changing Water Resources: An Ethnobiological Perspective from the Daasanach, Kenya

2021

The fast and widespread environmental changes that have intensified in the last decades are bringing disproportionate impacts to Indigenous Peoples and Local Communities. Changes that affect water resources are particularly relevant for subsistence-based peoples, many of whom already suffer from constraints regarding reliable access to safe water. Particularly in areas where water is scarce, climate change is expected to amplify existing stresses in water availability, which are also exacerbated by multiple socioeconomic drivers. In this paper, we look into the local perceptions of environmental change expressed by the Daasanach people of northern Kenya, where the impacts of climate change …

Early exposure to predation risk carries over metamorphosis in two distantly related freshwater insects

2017

1. Predation and competition play a central role in ecological communities, and it is increasingly recognised that animals use early warning cues to reduce the impact of these antagonistic interactions. 2. Strategies to avoid risk can occur during embryo development through plasticity in egg hatching time. This strategy, and its associated costs and carryover effects on adults are little understood in insects. In this study, these are explored in two distantly related freshwater insects: the damselfly Ischnura elegans and the mosquito Aedes albopictus. 3. As predicted, damselfly eggs hatched earlier in response to larval predators cues, a treatment that also affected adult size. Risk cues d…

Stream restorations with meanders increase dragonfly and damselfly diversity and abundance, including an endangered species.

2021

10 pages; International audience; This study presents examples of successful restoration projects for biodiversity conservation. In West France, the Pinail National Nature Reserve is a protected wetland interspersed with more than 6000 ponds. This wetland is inhabited by 50 species of Odonata and thus is a key biodiversity area for damselflies and dragonflies conservation. In the past, when the limestone was exploited, the streams of the plateau were artificially channeled rectilinearly, running to the Vienne River. Eventually streams were blocked by biomass and sediments resulting in water flowing mainly underground. In 2011, two restoration projects dug and recreated lost habitats such as…

Behavioural responses of fish groups exposed to a predatory threat under elevated CO2

2019

Most of the studies dealing with the effects of ocean acidification (OA) on fish behaviour tested individuals in isolation, even when the examined species live in shoals in the wild. Here we evaluated the effects of elevated CO2 concentrations (i.e. ∼900 μatm) on the shelter use and group cohesion of the gregarious damselfish Chromis viridis using groups of sub-adults exposed to a predatory threat. Results showed that, under predatory threat, fish reared at elevated CO2 concentrations displayed a risky behaviour (i.e. decreased shelter use), whereas their group cohesion was unaffected. Our findings add on increasing evidence to account for social dynamics in OA experiments, as living in gro…

Bioethics and neuroethics

2019

Neuroethics officially appeared at the start of the 21st century due to the progress made by the neurosciences, as an applied ethics related to bioethics, but also as an independent discipline in its own right. As an applied ethics, it tackles issues bordering on bioethics. As independent neuroethics, it deals with established philosophical problems from a neuroscientific standpoint in the broader sense. It involves two central questions: the design of a framework in which to select, interpret and integrate data from neuroscience on morality and outlining the appropriate method or methods for this new branch of knowledge. In both cases, most neuroethicists curiously claim to take a naturali…

2018

Odonate (damselfly and dragonfly) species richness and species occupancy frequency distributions (SOFDs) were analyzed in relation to geographical location in standing waters (lakes and ponds) in Fennoscandia, from southern Sweden to central Finland. In total, 46 dragonfly and damselfly species were recorded from 292 waterbodies. Species richness decreased to the north and increased with waterbody area in central Finland, but not in southern Finland or in Sweden. Species occupancy ranged from 1 up to 209 lakes and ponds. Over 50% of the species occurred in <10% of the waterbodies, although this proportion decreased to the north. In the southern lakes and ponds, none of the species occurred …

Trail-following pheromones in basal termites, with special reference to Mastotermes darwiniensis

2007

0098-0331 (Print) Journal Article; In the framework of an evolutionary study, trail pheromones have been studied in the most basal extant termite, Mastotermes darwiniensis (Mastotermitidae), and two other basal termites, the Termopsidae Porotermes adamsoni (Porotermitinae) and Stolotermes victoriensis (Stolotermitinae). Although workers of M. darwiniensis do not walk in single file while exploring a new environment under experimental conditions and are unable to follow artificial trails in 'open field' experiments, they do secrete a trail-following pheromone from their sternal glands. This unique behavior might reflect a primitive function of communication of the sternal gland. The major co…