77 research outputs found
Distribution et abondance des mouches piqueuses (Glossinidae, Stomoxys et Tabanidae) dans deux parcs nationaux du Gabon.
11 pagesInternational audienceIn order to minimize risks of pathogen transmission with the development of ecotourism in Gabon, a seasonal inventory has been performed in five contrasted biotopes in Ivindo (INP) and Moukalaba-Doudou (MDNP) National Parks. A total of 10,033 hematophagous flies were captured. The Glossinidae, with six different species identified, was the most abundant group and constitutes about 60% of the captured flies compared to the Stomoxys (6 species also identified) and Tabanidae with 28% and 12%, respectively. The Glossinidae showed a higher rate of capture in primary forest and in research camps. In INP, the Stomoxys showed a higher rate of capture in secondary forest and at village borders, whereas in MDNP the Stomoxys were captured more in the savannah area. Thus, each fly group seemed to reach maximum abundance in different habitats. The Glossinidae were more abundant in primary forest and near research camps while Stomoxys were more abundant in secondary forest and savannah. The Tabanidae did not show a clear habitat preference.Afin de minimiser les risques de transmission de pathogĂšnes avec le dĂ©veloppement de lâĂ©cotourisme au Gabon, un inventaire saisonnier a Ă©tĂ© menĂ© dans cinq biotopes caractĂ©ristiques des parcs nationaux de lâIvindo (PNI) et de Moukalaba-Doudou (PNMD). Au total, 10 033 mouches hĂ©matophages ont Ă©tĂ© capturĂ©es. Les Glossinidae, avec 6 espĂšces diffĂ©rentes identifiĂ©es, constituaient le groupe le plus abondant avec 60 % de mouches capturĂ©es, suivi des Stomoxys (6 espĂšces diffĂ©rentes identifiĂ©es) et des Tabanidae avec respectivement 28 % et 12 %. Les glossines ont Ă©tĂ© majoritairement capturĂ©es en forĂȘt primaire et au niveau des camps de recherche. Au PNI, les stomoxes ont Ă©tĂ© majoritairement capturĂ©s en forĂȘt secondaire et en pĂ©riphĂ©rie des villages. Alors quâau PNMD, ces stomoxes ont Ă©tĂ© majoritairement capturĂ©s au niveau des savanes. Ainsi, chaque groupe de mouches semble ĂȘtre infĂ©odĂ© Ă un type de milieu. Les glossines prĂ©fĂšrent la forĂȘt primaire et camps de recherche, alors que les stomoxes prĂ©fĂšrent la forĂȘt secondaire et la savane. Les tabanides ne dĂ©gagent aucune prĂ©fĂ©rence particuliĂšre pour un type de milieu
Deleterious effects of thermal and water stresses on life history and physiology: a case study on woodlouse
We tested independently the influences of increasing temperature and decreasing moisture on life history and physiological traits in the arthropod Armadillidium vulgare. Both increasing temperature and decreasing moisture led reproductive success to decrease. While the density of immune cells decreased and the ÎČ-galactosidase activity increased with increasing temperature and decreasing moisture, which suggests a negative impact of these stressors on individual performance, increased temperature and decreased moisture affected differently the other biomarkers conjuring different underlying mechanisms depending on the stress applied. Our findings demonstrate overall a negative impact of high temperature and low moisture on woodlouse welfare. Changing temperature or moisture had slightly different effects, illustrating the need to test further the respective role of each of these key components of climate change on organisms to predict more reliably the future of our ecosystems
Touchy matter: the delicate balance between Morganâs canon and open-minded description of advanced cognitive skills in the animal
A recommendation â based on reviews by ValĂ©rie Dufour and Alex Taylor â of the article: Farrar, B. G. (2020). Evidence of tool use in a seabird? PsyArXiv, 463hk, ver. 5 recommended and peer-reviewed by Peer Community In Ecology. doi: 10.31234/osf.io/463h
Optimal foraging in a changing world: old questions, new perspectives
A recommendation of : Calcagno V, Hamelin F, Mailleret L, and Grognard F. How optimal foragers should respond to habitat changes? On the consequences of habitat conversion. bioRxiv 273557 (2018), ver. 4 peer-reviewed and recommended PCI Ecology.International audienc
Butinage collectif chez l'abeille Apis mellifera L.: étude théorique et expérimentale
Ce travail de thĂšse a portĂ© sur le comportement de butinage coopĂ©ratif chez lâabeille. Dans un environnement hĂ©tĂ©rogĂšne oĂč les ressources alimentaires sont distribuĂ©es de maniĂšre discrĂšte, la collecte de nectar chez cet insecte social met en jeu non seulement des processus individuels dâorientation et dâapprentissage, mais aussi des processus collectifs reposant sur une communication vibratoire et phĂ©romonale intense entre les membres de la colonie qui agissent de façon coordonnĂ©e. Pour rendre compte de ces phĂ©nomĂšnes, jâai adoptĂ© une double approche thĂ©orique et expĂ©rimentale. A partir des donnĂ©es recueillies lors dâexpĂ©rimentations conduites au laboratoire, jâai Ă©tudiĂ© certaines transitions entre les diffĂ©rents comportements impliquĂ©s dans le butinage (modĂšles Ă risques proportionnels). Jâai en outre dĂ©veloppĂ© un modĂšle mathĂ©matique (systĂšme dynamique non linĂ©aire) du comportement de butinage. Les propriĂ©tĂ©s de ce modĂšle ont Ă©tĂ© Ă©tudiĂ©es et nous avons dĂ©gagĂ© plusieurs prĂ©dictions thĂ©oriques. Ce travail mâa dâune part conduit Ă reconsidĂ©rer le langage de lâabeille dans un contexte dâĂ©cologie comportementale et Ă proposer un scĂ©nario de lâĂ©volution de la communication de la distance chez les apoĂŻdes. Dâautre part, les protocoles expĂ©rimentaux et les outils dâanalyse statistique dĂ©veloppĂ©s dans cette thĂšse ont Ă©tĂ© utilisĂ©s pour Ă©valuer lâimpact de produits phytosanitaires (pesticides, entomotoxines issues de plantes transgĂ©niques) sur le comportement de butinage collectif des abeilles
Le choix du partenaire : une force évolutive sous-estimée.
8 pagesNational audienc
A dynamic game theoretical model predicts variance in choosiness when mate availability fluctuates
RésuméInternational audienc
Pairing patterns in relation to body size, genetic similarity and multilocus heterozygosity in a tropical monogamous bird species.
9 pagesInternational audienceThe relative influence of genetic and phenotypic quality on pairing status and mating patterns in socially monogamous species remains poorly documented. We studied social status and pairing patterns in relation to genetic similarity and multilocus heterozygosity (MLH) estimates from 11 microsatellite markers, and both tarsus length and wing chord (as a measure of competitive ability in territorial defence) in a socially monogamous tropical bird species where individuals defend territories year-round, alone or in pairs, the Zenaida dove, Zenaida aurita. Tarsus length and wing chord did not differ between unpaired territorial birds and paired ones in either sex, whereas paired females, but not paired males, tended to be more heterozygous than unpaired ones. Among 84 pairs, we found no evidence for assortative mating for tarsus length, wing chord, MLH or genetic similarity. However, within pairs, male wing chord was positively related to female MLH and female tarsus length was positively related to male MLH, with no evidence for local effects, suggesting assortative mating by individual quality. Although the observed pattern of mating in Zenaida doves may be the product of mutual mate choice, further assessment of this hypothesis requires direct investigation of both mating preference in each sex and lifetime reproductive success in relation to body size and MLH
Sexing birds using discriminant function analysis: a critical appraisal.
9 pagesInternational audienceDiscriminant function analysis (DFA) based on morphological measurements is a quick, inexpensive, and efficient method for sex determination in field studies on cryptically monomorphic bird species. However, behind the apparent standardization and relative simplicity of DFA lie subtle differences and pitfalls that have been neglected in some studies. Most of these concerns directly affect assessment of the discriminant performance, a parameter of crucial importance in practice because it provides a measure of the quality of an equation that may be used in later field studies. Using results from 141 published studies and simulations based on a large data set collected on adult Zenaida Doves (Zenaida aurita), we assessed the effects of sexual dimorphism, sample size, and validation methods on discrimination rates. We compared the three most common methods used to estimate the proportion of correctly classified males and females by DFA: resubstitution, jackknife, or sample splitting. Results from simulations indicate that these procedures may lead to opposite conclusions, especially when the sample size is small. In particular, the resubstitution techniques appear to be overoptimistic, and we therefore recommend that DFA accuracy be estimated by the jackknife cross-validation procedure. In addition, we show that most previous studies failed to present DFA accuracy with 95% confidence intervals, which hampers comparisons among studies. Finally, our results suggest that large sample sizes should be preferred over repeated measurements of the same individuals, because random measurement error is likely to have only a weak effect on the accuracy of the discriminant rate
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