Papers by emmanuel desouhant
<strong>Type:</strong> Data<br> <strong>Title:</strong> Insects and... more <strong>Type:</strong> Data<br> <strong>Title:</strong> Insects and incest: sib-mating tolerance in natural populations of a parasitoid wasp (http://dx.doi.org/10.24072/pci.evolbiol.100047)<br> <strong>Authors:</strong> Marie Collet, Isabelle Amat, Sandrine Sauzet, Alexandra Auguste, Xavier Fauvergue, Laurence Mouton, Emmanuel Desouhant<br> Open access data<br> CC-BY-NC <strong>Data:</strong><br> <em>Microsatellite genotyping:</em> Collet_Microsatellite-genotyping_2018.txt Genotyping of Venturia canescens individuals on 18 microsatellite loci.<br> The IDs of wild individuals consist of PopulationName_Sex_ID, ex: Nice_femelle_12 is the wild female n°12 from Nice population (femelle=female).<br> The IDs of wild females' offspring consist of PopulationName_desc_SexOffspring_IDMother.IDOffspring, ex: Valence_desc_male_20.1 is the male offspring n° 1 of the Valence wild female n° 20. <em> Mate choice behaviour:</em> Collet_MateChoiceBehaviour_2018.txt Mate choice experiement conditions.<br> Fem_ID = Female ID, Male_Density: D = 9 males, d = 3 males, Brother_Freq: F = 2/3 of brothers, f = 1/3 of brothers, Female_fam = Name of female family, Col_Bro = Paint colour use to distinguish the brothers, Col_Unrel = Paint colour use to distinguish the unrelated males. Collet_MateChoiceBehaviour1_2018.txt Mate choice experiement data.<br> Fem_ID = Female ID, Male_Density: D = 9 males, d = 3 males, Brother_Freq: F = 2/3 of brothers, f = 1/3 of brothers, Female_fam = Name of female family.<br> Mate: 1 at the time of mating, 0 otherwise. Mate_Bro: for each female, 1 if she mated with a brother, 0 otherwise (Mating with an unrelated male or no mating). Therefore, for each female data last line, there are three possibilities: Mate = 0, Mate_Bro = 0 -&gt; No mating after 30 min, censored; Mate = 1, Mate_Bro = 0 -&gt; Mating with an Unrelated male; Mate = 1, Mate_Bro = 1 -&gt; Mating with a Brother.<br> start/end: beginning/end of male courtship behaviour (min'sec)<br> Reject_Bro/Reject_U [...]
The immediate and delayed effects of density are key in determining population dynamics, since th... more The immediate and delayed effects of density are key in determining population dynamics, since they can positively or negatively affect the fitness of individuals. These effects have great relevance for polyphagous insects for which immature stages develop within a single site of finite feeding resources. Drosophila suzukii is a crop pest that induces severe economic losses for agricultural production, however little is known about the effects of density on its life-history traits. In the present study, we (i) investigated the egg distribution resulting from females’ egg-laying strategy and (ii) tested the immediate and delayed effects of larval density on emergence rate, development time, sex ratio of offspring, fecundity and adult size (a range of 1 to 50 larvae was used). We showed that most of fruits contain several eggs and aggregate of eggs of high density can be found in some fruits. This high density has no immediate effects on the emergence rate, but has effect on larval de...
Interactions insectes-plantes
PLOS ONE, 2020
Sib mating increases homozygosity, which therefore increases the risk of inbreeding depression. S... more Sib mating increases homozygosity, which therefore increases the risk of inbreeding depression. Selective pressures have favoured the evolution of kin recognition and avoidance of sib mating in numerous species, including the parasitoid wasp Venturia canescens. We studied the female neurogenomic response associated with sib mating avoidance after females were exposed to courtship displays by i) unrelated males or ii) related males or iii) no courtship (controls). First, by comparing the transcriptional responses of females exposed to courtship displays to those exposed to controls, we saw a rapid and extensive transcriptional shift consistent with social environment. Second, by comparing the transcriptional responses of females exposed to courtship by related to those exposed to unrelated males, we characterized distinct and repeatable transcriptomic patterns that correlated with the relatedness of the courting male. Network analysis revealed 3 modules of specific 'sibresponsive' genes that were distinct from other 'courtship-responsive' modules. Therefore, specific neurogenomic states with characteristic brain transcriptomes associated with different behavioural responses affect sib mating avoidance behaviour.
Scientific Reports, 2021
Spotted wing drosophila (SWD) causes significant economic loss in fruit crops to growers worldwid... more Spotted wing drosophila (SWD) causes significant economic loss in fruit crops to growers worldwide. There is immediate need for efficacious and selective monitoring tools that can detect infestations early. Previously, volatile organic compounds derived from apple were studied and a quinary chemical component blend (QB) was identified as the key SWD attractant in a blueberry orchard in the United States. This study’s aim was to determine whether previously observed QB efficacy, selectivity, and early detection levels could be attained within raspberry and cherry fields in the USA and Europe. Results demonstrated that sticky trap baited QB dispenser provided earlier SWD detection potential than the usually adopted apple cider vinegar (ACV) trap. The number of SWD captured/trap by QB baited trapping systems was significantly lower than that of the ACV trap. However, percent SWD/trap of QB baited traps was same within cherry. Lower non-target capture will save farmer/grower’s labor and...
Environmental Pollution, 2020
Artificial Light At Night (ALAN) is an emerging pollution, that dramatically keeps on increasing ... more 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 disruption of natural light cycles due to ALAN is particularly expected for nocturnal species, which require dark periods to forage, move, and reproduce. Despite the growing number of studies on this subject, our knowledge on the direct influence of nocturnal lighting on amphibians, the most endangered vertebrate, is still scarce. Apart from chiropterans, amphibians contain the largest proportion of nocturnal species among vertebrates exhibiting an unfavourable conservation status in most parts of the world and living in ALAN polluted areas. To better understand the consequences of ALAN on the breeding component of amphibian fitness, we experimentally exposed male breeding common toads (Bufo bufo) to ecologically relevant light intensities of 0.01 (control), 0.1 or 5 lux for 12 days. At mating, exposed males took longer than controls to form an amplexus, i.e., to pair with a female, and broke amplexus before egg laying, while controls never did. These behavioural changes were associated with fitness alteration. The fertilization rate of 5 luxexposed males was reduced by 25%. Salivary testosterone, which is usually correlated with reproductive behaviours, was not altered by ALAN. Our study demonstrates that ALAN can affect the breeding behaviour of anuran species and reduce one component of their fitness. Given the growing importance of ALAN, more work is needed to understand its long-term consequences on the behaviour and physiology of individuals. It appears essential to identify deleterious effects for animal populations and propose appropriate management solutions in an increasingly brighter world. Capsule summarizing the main finding: Artificial light at night decreased the capacity of male Bufo bufo to form a pair with a female and reduced their fertilization success.
PloS one, 2017
Differences in learning and memory dynamics between populations are suspected to result from diff... more Differences in learning and memory dynamics between populations are suspected to result from differences in ecological constraints such as resource distribution. The two reproductive modes (strains) of the parasitoid wasp Venturia canescens share the same geographical areas but live in contrasting habitats: arrhenotokous wasps live in the wild (generally orchards), whereas thelytokous ones live mostly in stored-products buildings (e.g. granaries). This species thus represents a relevant biological model for understanding the relationship between the ecological constraints faced by a species and its memory and learning ability. We showed that after having laid eggs in presence of both a synthetic odour and natural olfactory cues of their host, arrhenotokous wasps exhibited a change in their behavioural response towards the synthetic odour that was at least as pronounced as in thelytokous ones even though they were faster in their decision-making process. This is consistent with bette...
Scientific Reports, 2017
Animal medication is a behavioral strategy to resist enemies based on the use of substances from ... more Animal medication is a behavioral strategy to resist enemies based on the use of substances from the environment. While it has been observed in several animals, whether invasive species can use medication to resist new enemies during its expansion is unknown. Here, we show that the worldwide invasive pest Drosophila suzukii performs trans-generational prophylactic medication by adapting its oviposition behavior in the presence of enemies. We find that flies preferentially lay their eggs on media containing atropine-an entomotoxic alkaloid-in the presence of parasitoids. We further show that flies developing on atropine more efficiently resist parasitization by parasitoids. Finally, we find that developing in hosts reared on atropine strongly impacts the life-history traits of parasitoids. This protective behavior is reported for the first time in a pest and invasive species, and suggests that animal medication may be an important driver of population dynamics during invasions.
BMC Ecology, 2015
Background: Single-locus complementary sex determination (sl-CSD), which occurs in some insects o... more Background: Single-locus complementary sex determination (sl-CSD), which occurs in some insects of the order Hymenoptera, imposes a heavy genetic load that can drive small populations to extinction. The core process in these species is the development of individuals homozygous at the sex-determining locus into unfit diploid males. The risk of extinction of populations with sl-CSD is theoretically much higher if diploid males are viable and capable of mating but sterile, because diploid males then decrease the reproductive output of both their parents and the females with which they mate. Results: In the parasitoid wasp Venturia canescens (Hymenoptera: Ichneumonidae), diploid males resembled their haploid counterparts in most respects, but their mating success was nevertheless lower than that of haploid males, especially when the two types of males were placed in competition. Furthermore, although diploid males transferred viable sperm during copulation, they sired no daughters: the females with which they mated produced only sons, like virgin females. A simulation model combining behavior, genetics and demography demonstrated that for two alternative hypotheses concerning the fertilization success of diploid sperm, the mating success of diploid males strongly affected population dynamics. Conclusion: The performance of diploid males should be estimated in competitive situations. It is a crucial determinant of the probability of extinction.
Biological Journal of the Linnean Society, 2014
Hymenopterans under single-locus complementary sex determination (sl-CSD) face inbreeding costs d... more Hymenopterans under single-locus complementary sex determination (sl-CSD) face inbreeding costs due to this sex determination mode. Under sl-CSD, homozygote eggs at the sl-CSD locus usually develop into unviable or sterile diploid males. Production of such costly males increases when sib-mating happens because related individuals share half of their genome. In the hymenopteran Venturia canescens (a solitary parasitoid wasp), diploid males are sterile, leading to fitness costs through genetic incompatibility between parents. Whereas the costs of producing diploid males and behavioural strategies that would reduce such costs have been studied in females, the potential fitness costs faced by males have not. Here, we aimed to investigate fitness costs that males endure after a single sib-mating and tested whether they have the ability to avoid sib-mating through kin recognition. Our results show that males have a reduced fitness (i.e. they produce fewer daughters) when mating with their sibs. We also show that males have the ability to distinguish between non-sib and sib females (i.e. kin). They use chemical marks emitted by the females to discriminate kin from non-kin. We discuss the evolution of kin recognition in males in the context of mate choice for genetic compatibility.
Oecologia, 2002
Diversified bet-hedging for life cycle duration is defined as within-generation variability in cy... more Diversified bet-hedging for life cycle duration is defined as within-generation variability in cycle length expressed by a single genotype maximising mean geometric fitness. Such plasticity is not predictive, i.e. it is not a response to cues from the environment that has a predictive value for the decision at hand. In evolutionary terms, diversified bet-hedging is perceived as an adaptation to environmental stochasticity. However, clear evidence of bet-hedging is scarce and exists only for a few desert plant species and one desert bee. In temperate insects, diversified bet-hedging for life cycle duration has been suspected in the chestnut weevil, but proximate factors responsible for individual variation are still unknown. From field experiments, we show that the frequency of the long cycle depends on larval weight and on the date when a larva abandons the fruit, but not on larval burying depth in the soil. Since the two first factors are known to depend on food and temperature and cannot lead to predictive plasticity, we give evidence of bet hedging in this temperate species. Indeed, despite a cost associated with prolonged diapause (extra mortality and loss of reproductive opportunity), a previous study showed that plasticity for life cycle duration, such as discussed in this paper, maximises mean geometric fitness and persistence probability in the chestnut weevil. We propose the hypothesis that the variation in life cycle duration depends on individual variability of metabolic resources such as lipids.
European Journal of Entomology, 2013
Endosymbiotic organisms are known to manipulate the reproductive biology of their hosts. Incomple... more Endosymbiotic organisms are known to manipulate the reproductive biology of their hosts. Incomplete prevalence of endosymbiont inducing thelytokous parthenogenesis results in the coexistence of sexual and asexual individuals, and could account for the maintenance of sexual reproduction in certain populations or species. In the parasitoid Venturia canescens, arrhenotokous ("sexual") and thelytokous ("asexual") individuals occur sympatrically. We aimed to determine whether endosymbionts are implicated in the thelytoky of V. canescens. After screening females of the two reproductive modes for several reproductive parasites: bacteria (Wolbachia, Rickettsia, Bacteroidetes, Spiroplasma, Arsenophonus) and Microsporidia, we concluded that thelytoky in V. canescens is not induced by any of these parasites and confirmed its suitability as a biological model for solving the evolutionary enigma of the maintenance of sexual reproduction.
Behavioral Ecology, 2006
Animals foraging for patchily distributed resources may optimize their foraging decisions concern... more Animals foraging for patchily distributed resources may optimize their foraging decisions concerning the patches they encounter, provided that they base these decisions on reliable information about the profitability of the habitat as a whole. Females of the parasitoid Lysiphlebus testaceipes exploit aphid hosts, which typically aggregate in discrete colonies. We show here how betweencolony travel time and the number of aphids in previously visited colonies affect parasitoid foraging behavior. We first assumed that parasitoids use travel time and previous colony size to estimate a mean rate of fitness gain in the habitat and derived quantitative predictions concerning the effect of these two variables on patch residence time and patch-leaving rate of attack. We then tested these theoretical predictions in laboratory experiments in which female parasitoids were allowed to visit two successive colonies. As predicted, the observed residence time in the second colony increased with increasing travel time and decreasing size of the first colony. Patch-leaving rate of attack decreased with increasing travel time but was not affected by previous colony size. These results suggest that parasitoids use these two variables to assess habitat quality. However, discrepancies between the data obtained and quantitative predictions show that the effect of travel time on patch use may be more complex than assumed in our model.
and internal state modulates host-patch exploitation in a parasitic wasp
Current Opinion in Insect Science, 2018
PLoS ONE, 2010
Background: When some combinations of maternal and paternal alleles have a detrimental effect on ... more Background: When some combinations of maternal and paternal alleles have a detrimental effect on offspring fitness, females should be able to choose mates on the basis of their genetic compatibility. In numerous Hymenoptera, the sex of an individual depends of the allelic combination at a specific locus (single-locus Complementary Sex Determination), and in most of these species individuals that are homozygous at this sexual locus develop into diploid males with zero fitness. Methods and Findings: In this paper, we tested the hypothesis of genetic incompatibility avoidance by investigating sibmating avoidance in the solitary wasp parasitoid, Venturia canescens. In the context of mate choice we show, for the first time in a non-social hymenopteran species, that females can avoid mating with their brothers through kin recognition. In ''no-choice'' tests, the probability a female will mate with an unrelated male is twice as high as the chance of her mating with her brothers. In contrast, in choice tests in small test arenas, no kin discrimination effect was observed. Further experiments with male extracts demonstrate that chemical cues emanating from related males influence the acceptance rate of unrelated males. Conclusions: Our results are compatible with the genetic incompatibility hypothesis. They suggest that the female wasps recognize sibs on the basis of a chemical signature carried or emitted by males possibly using a ''self-referent phenotype matching'' mechanism.
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Papers by emmanuel desouhant