Artifical light at night triggers slight transcriptomic effects on melatonin signaling but not synthesis in tadpoles of two anuran species.

The worldwide expansion of artificial light at night (ALAN) is acknowledged as a threat to biodiversity through alterations of the natural photoperiod triggering the disruption of physiological functions. In vertebrates, melatonin production during the dark phase can be decreased or suppressed by nocturnal light as shown in many taxa. But the effect of ALAN at low intensity mimicking light pollution in peri-urban area has never been investigated in amphibians.

Artificial light at night decreases the pupillary light response of dark-adapted toads to bright light.

Artificial light at night (ALAN) is expanding worldwide. Many physiological effects have been reported in animals, but we still know little about the consequences for the visual system. The pupil contributes to control incoming light onto the retina.

Transcriptome-wide deregulation of gene expression by artificial light at night in tadpoles of common toads.

Artificial light at night (ALAN) affects numerous physiological and behavioural mechanisms in various species by potentially disturbing circadian timekeeping systems and modifying melatonin levels. However, given the multiple direct and indirect effects of ALAN on organisms, large-scale transcriptomic approaches are essential to assess the global effect of ALAN on biological processes. Moreover, although studies have focused mainly on variations in gene expression during the night in the presence of ALAN, it is necessary to investigate the effect of ALAN on gene expression during the day.

Discrimination of conspecifics from heterospecifics in a hybrid zone: Behavioral and chemical cues in ants.

Species and nestmate recognition in social insects occurs mostly through cuticular hydrocarbons acting as chemical cues. These compounds generate a colony-specific odor profile depending on genetic and environmental factors. Species and nestmate recognition results in specific behavioral responses, regulating the level of aggression toward other individuals during an interaction.

Ecdysteroids affect female reproductive status and outcome of contest over hosts in the parasitoid wasp Eupelmus vuilleti.

Ecdysteroids are a family of insect hormones that may play a role in modulating aggressive behavior in reproductive contexts. In Hymenoptera, the few studies investigating the link between ecdysteroid titers, reproduction and aggressiveness during contests concern solely eusocial species. Here, we explored whether ecdysteroid titers influenced female reproductive status as well as aggressiveness and resolution of conflict in a solitary ectoparasitoid, Eupelmus vuilleti (Hymenoptera: Eupelmidae).

Artificial light at night alters the sexual behaviour and fertilisation success of the common toad.

Artificial Light At Night (ALAN) is an emerging pollution, that dramatically keeps on increasing worldwide due to urbanisation and transport infrastructure development. In 2016, it nearly affected 23% of the Earth's surface. To date, all terrestrial and aquatic ecosystems have been affected.

The role of associative learning process on the response of fledgling great tits (Parus major) to mobbing calls.

When they detect a predator, many species emit anti-predator vocalizations. In some cases, they emit mobbing calls, which are associated with the caller approaching and harassing the predator while attracting others to join it. Surprisingly, although mobbing has been widely reported in adults of numerous species, there has been no test of the role of learning in mobbing call recognition, especially during ontogeny.

Artificial light at night disturbs the activity and energy allocation of the common toad during the breeding period.

The presence of artificial light at night (ALAN) is currently a global phenomenon. By altering the photoperiod, ALAN may directly affect the physiology and behaviour of many organisms, such as the timing of daily rhythms, hormonal regulation, food intake, metabolism, migration and reproduction. Surprisingly while it is known that ALAN exposure strongly influences health of humans and laboratory animals, studies on wildlife remain scarce.

Variability of surface and underwater nocturnal spectral irradiance with the presence of clouds in urban and peri-urban wetlands.

Artificial light at night (ALAN) is an increasing phenomenon worldwide. It causes a wealth of biological and ecological effects that may eventually affect populations and ecosystems. Despite the growing concern about ALAN, little is known about the light levels species are exposed to at night, especially for wetlands and underwater habitats.

Doping for sex: Bad for mitochondrial performances? Case of testosterone supplemented Hyla arborea during the courtship period.

Sexual selection has been widely explored from numerous perspectives, including behavior, ecology, and to a lesser extent, energetics. Hormones, and specifically androgens such as testosterone, are known to trigger sexual behaviors. Their effects are therefore of interest during the breeding period.

Immune challenges and visual signalling in tree frogs.

In animals, mate-choice is often based on sexual signals that carry information and help the receiver make the best choice to improve the receiver's fitness. Orange visual sexual signals have been hypothesised to carry immune information because they are often due to carotenoid pigments which are also involved in immunity response. Although many studies have focused on the direct relationships between coloration and immunocompetence, few studies have simultaneously studied immunocompetent response and coloration variation after an immune challenge.

Does testosterone affect foraging behavior in male frogs?

During the breeding season, males often produce costly and extravagant displays or physical ornaments to attract females. Numerous studies have established that testosterone could directly influence the expression of certain sexual signals. However, few of these studies have focused on the indirect role that testosterone could play in modulating prey detection and visual performance to improve the foraging ability of males and hence their acquisition of nutritional resource.

Effects of traffic noise on tree frog stress levels, immunity, and color signaling.

During the last decade, many studies have focused on the detrimental effects of noise pollution on acoustic communication. Surprisingly, although it is known that noise exposure strongly influences health in humans, studies on wildlife remain scarce. In order to gain insight into the consequences of traffic noise exposure, we experimentally manipulated traffic noise exposure as well as the endocrine status of animals to investigate physiological and phenotypic consequences of noise pollution in an anuran species.

Impact of cadmium on the ecdysteroids production in Gammarus fossarum.

Gammarus fossarum is an important test organism which is currently used as a bio-indicator as well as in ecotoxicological tests. Nevertheless, data on ecdysteroids in endocrine toxicity test are not yet available for these species, despite its crucial role in molting and reproduction. In the present paper, ecdysteroids concentrations were studied during the molt cycle (in females) and embryonic development in G.

The proximal costs of case construction in caddisflies: antioxidant and life history responses.

Animal construction allows organisms to cope with environmental variations but the physiological costs of such behaviour are still poorly understood. The aim of the present study was to measure the physiological cost of construction behaviour through the oxidative balance that is known to affect the ability of organs to function, stimulates senescence processes and ultimately impacts the fitness of the organism. We used larvae of caddisfly, Limnephilus rhombicus, by experimentally modifying the effort associated with case building.

The energetic costs of case construction in the caddisfly Limnephilus rhombicus: direct impacts on larvae and delayed impacts on adults.

Caddisflies, whose aquatic larvae build a portable case with silk, are a suitable model organism to test the impacts of resource allocation trade-off during development and examine the evolution of life-history strategies. In the caddisfly Limnephilus rhombicus, adult feeding is minimal. Therefore, the whole resources are acquired during the larval phase and must be allocated to case construction, growth and reproduction.

Reproduction in a variable environment: How does Eupelmus vuilleti, a parasitoid wasp, adjust oogenesis to host availability?

Oogenesis of the parasitoid wasp Eupelmus vuilleti is known to be dependent on host availability. However, examination of ovarian dynamics by microscopy showed that oogenesis and vitellogenesis are initiated before female eclosion and proceed 1-2 days after, independent of host presence. Oogenesis continued beyond the 2nd day only in the presence of hosts, otherwise it was replaced by egg resorption.

Host-induced ecdysteroids in the stop-and-go oogenesis in a synovigenic parasitoid wasp.

Eupelmus vuilleti (Hymenoptera; Eupelmidae) is a solitary ectoparasitoid producing yolk-rich eggs. The female oviposits mainly on the fourth larval instar of Callosobruchus maculatus (Coleoptera; Bruchidae), which develop within pods and seeds of Vigna unguiculata (Fabacae). Parasitoid females are synovigenic, i.

Importance of sterols acquired through host feeding in synovigenic parasitoid oogenesis.

Eupelmus vuilleti (Hymenoptera; Eupelmidae) is a host feeding ectoparasitoid of fourth-instar larvae or pupae of Callosobruchus maculatus (Coleoptera; Bruchidae) infecting Vigna unguiculata seed and pods (Fabacae). Parasitoid females are synovigenic, i.e.

Sources of chemical signals which enhance multiparasitism preference by a cleptoparasitoid.

The cleptoparasitoid Eupelmus vuilleti recognizes and prefers laying on hosts parasitized by Dinarmus basalis to unparasitized hosts. This recognition is based on the perception of a chemical substance deposited on the surface of the seed. Dufour's gland secretion and cuticular hydrocarbons of D.

Increased sulfur precursors and volatiles production by the leek Allium porrum in response to specialist insect attack.

To defend themselves against herbivory, plants use a variety of direct and indirect strategies involving induced increases in secondary substances. Species of the Allium genus (Alliaceae), such as the leek Allium porrum (L.), produce nonprotein sulfur amino acids derived from cysteine, i.

Host-plant finding by the asparagus fly, Plioreocepta poeciloptera (Diptera: Tephritidae), a monophagous, monovoltine tephritid.

The role of various olfactory and visual stimuli was studied in host-plant finding by the asparagus fly Plioreocepta poeciloptera (Schrank), a monophagous monovoltine tephritid causing serious damage to asparagus spears. Volatiles released by asparagus plants were extracted by diethyl ether after cryotrapping concentration, and identified by gas chromatography-mass spectrometry. Twelve of the 13 compounds identified were tested using electroantennography to measure the response of the fly.

Blending in with the crowd: social parasites integrate into their host colonies using a flexible chemical signature.

Social parasites are able to exploit their host's communication code and achieve social integration. For colony foundation, a newly mated slave-making ant queen must usurp a host colony. The parasite's brood is cared for by the hosts and newly eclosed slave-making workers integrate to form a mixed ant colony.

Aroma analysis of fresh and preserved onions and leek by dual solid-phase microextraction-liquid extraction and gas chromatography-mass spectrometry.

The lachrymatory factor (thiopropanal-S-oxide) was directly analysed on fresh onion (Allium cepa) juice by solid-phase microextraction (polyacrylate fibre) using a fast routine GC-MS method on a 10 m x 0.32 mm I.D.