Welcome to the Alpine Marmot Project
tel. : +49 (0)4421 9689 44
Institut für Vogelforschung “Vogelwarte Helgoland”
(Institute of Avian Research)
An der Vogelwarte 21, Wilhelmshaven
Holds a PhD in evolutionary ecology at the University of Burgundy, Dijon. My main research is to link behavioral ecology, immuno-ecology and molecular ecology to understand the origin and maintenance of genetic variability in natural populations.
My current work (started in August 2016) focuses on a long-term survey (24 years) of a common tern (Sterna hirundo) colony located in the Banter See on the German North coast. This long-term population study, which has also provided microsatellite genotypes and pedigrees, constitutes the perfect basis to study heterozygosity-fitness-correlations (HFC) using different fitness measures (survival, reproductive success) and across birds of different origin (immigrant/resident) or belonging to different age classes. I am also interested to explore which factors (as stress) can modify the trade-off between survival, reproduction and immunity. Hormonal stress measurements are developed and survival and reproduction data are already available. So, I would like, in the short-term, to measure different immune parameters (humoral, cellular and inflammation), as well as oxidative stress. In these long-lived sea birds, I also would like to investigate how anthropic factors (pollutants) can impact survival, reproduction and immunity and whether they can affect the life history trajectories of offspring.
Genetic diversity results from the interaction between different processes: some processes act on genome parts, such as mutations or recombination; others are independent of the genome and can affect it entirely, such as demographic processes. Other processes result from the exposure of genetic diversity at a given environment, such as natural or sexual selection. The contribution of each process in the evolution of genetic diversity remains poorly understood. By focusing on an emblematic species, the alpine marmot (Marmota marmota), I will try to disentangle the relative role of demographic and selective processes in genetic diversity currently observed in populations.
OBJECTIVE 1 – Assess and understand the neutral and adaptive genetic diversity – Numerous studies have shown that marmots had a relatively low genetic diversity, but the causes of this phenomenon are still unknown. By using selected (MHC genes) and neutral genetic markers, I will assess and compare individual and population genetic caracteristics in marmots living in the Alps and in the Pyrenees.
OBJECTIVE 2 – Determine genetic characteristics involved in mate choice – Mate choice is generally assumed to be involved in MHC genetic characteristics. Here we will look for genetic characteristics involved in mate choice in alpine marmots.
OBJECTIVE 3 – Identify demographic factors and selective processes involved in genetic diversity – By using fossil and long-term data samples, we will be able to study changes in genetic diversity at different time scales, and thus to understand the role of demographic events in the current and past genetic diversity. By comparing the MHC diversity of populations exposed to different evolutionary histories and to different selection pressures (different levels of inbreeding and disease), we will try to understand how the selection pressures and demographic processes may impact the genetic characteristics studied.
Past project – evolutionary ecology of avian malaria: host and environmental caracteristics effect
During my three years of PhD, I looked at how the host, the environment and their interactions could influence the evolution of avian malaria parasite, using the house sparrow (Passer domesticus) and domestic canary (Serinus canaria) as models.
In particular, I showed that a heavy metal contamination increased Plasmodium prevalence, whereas it had no effect on parasitaemia (Bichet et al. 2013). In another study, I showed that daily variations in temperature explained most of the variation in prevalence of Plasmodium, and had no effect on parasitaemia in the house sparrow across France (Loiseau et al. 2013) . These climatic analyzes allowed me to make predictions about the evolution of the long-term prevalence and suggest an increased prevalence in the north and west of the country. Meanwhile, I have shown that some host characteristics such as age, sex, (Bichet et al. 2013), social status (Larcombe et al., Submitted), nutritional status (Cornet et al. 2013 ) and immune capacity (Bichet et al. 2012) had an effect on parasitemia, but not on the prevalence. These studies seem to show that parasite prevalence and parasitic characteristics are independent and that the prevalence depends on the environmental context, while the parasitaemia depends on the characteristics of the host.
I also looked at how the level of inbreeding and parasitism could influence the genetic characteristics involved in mate choice. By following an insular population of house sparrow, I found that females preferentially chose genetically relative males, and that this choice seemed to be based on the characteristics of the genome as a whole, instead of being based on the characteristics of genes the Major Histocompatibility Complex (MHC Bichet et al. submitted). In addition, by comparing island populations and mainland populations, I found that island populations have a lower genetic variability and were more differentiated than mainland populations for neutral markers, while MHC variability was maintained in the islands. Levels of MHC differentiation are lower than for neutral markers, suggesting the existence of a balanced selection on these genes (Bichet et al. in prep).
Bichet C., Allainé D., Sauzet S. and Cohas A. (2016) Faithful or not: direct and indirect effects of climate on extra-pair paternities in a population of Alpine marmots. Proceedings of the Royal Society B, 283: 20162240. http://dx.doi.org/10.1098/rspb.2016.2240. pdf
Bichet C., Sauzet S., Averty L., Dupont P., Ferrandiz-Rovira M., Ferrari C., Figueroa I., Tafani M., Rézouki C., López BC., and Cohas, A. (2016) Multiple geographic origins and high genetic differentiation of the Alpine marmots reintroduced in the Pyrenees. Conservation Genetics, 17: 1157–1169. pdf
Bichet C., Moodley Y., Penn D.J., Sorci G. and Garnier S. 2015. Genetic structure in insular and mainland populations of house sparrows (Passer domesticus) and their hemosporidian parasites. Ecology and Evolution, 5(8): 1639-1652. pdf
Bichet, C., Penn, D., Moodley, Y., Dunoyer, L., Cellier-Holzem, E., Garnier, S., Sorci, G. 2014. Females tend to prefer genetically similar mates in an island population of house sparrows. BMC Evolutionary Biology, 14: 47. pdf
Bichet, C., Sorci, G., Robert, A., Julliard, R., Lendvai, A., Chastel, O., Garnier, S., and Loiseau, C. 2014. Epidemiology of Plasmodium relictum infection in the house sparrow. Journal of Parasitology, 100(1): 59-65. pdf
Larcombe, S., Bichet, C., Cornet, S., Faivre, B., and Sorci, G. 2013. Food availability and competition do not modulate the costs of Plasmodium infection in dominant male canaries. Experimental Parasitology, 135(4): 708-714. pdf
Cornet, S., Bichet, C., Larcombe, S., Faivre, B., and Sorci, G. 2013. Impact of host condition on infection dynamics and parasite virulence in a bird-malaria system. Journal of Animal Ecology, DOI: 10.1111/1365-2656.12113. pdf
Bichet, C., Scheifler, R., Cœurdassier, M., Julliard, R., Sorci, G., and Loiseau, C. 2013. Urbanization, trace metal pollution, and malaria prevalence in the house sparrow. PloSOne, 8(1). pdf
Loiseau, C., Harrigan, R. J., Bichet, C., Julliard, R., Garnier, S., Lendvai, A. Z., Chastel, O., and Sorci, G. 2012. Predictions of avian Plasmodium expansion under climate change. Nature Scientific Reports, 3. pdf
Bichet, C., Cornet, S., Larcombe, S., and Gabriele Sorci. 2012. Experimental inhibition of nitric oxide increases Plasmodium relictum (lineage SGS1) parasitaemia. Experimental Parasitology, 132(4): 417-423. pdf
Bichet C., Sorci G., Moodley Y., Penn D. (2012) Malaria aviaire, Complexe Majeur d’Histocompatibilité (CMH) et différenciation génétique chez le moineau domestique (Passer domesticus). Réseau Ecologie des Interactions Durable (REID), Rennes, France.
Bichet C., Sorci G., Moodley Y., Penn D. (2012) Malaria aviaire, Complexe Majeur d’Histocompatibilité (CMH) et différenciation génétique chez le moineau domestique (Passer domesticus). Réunion du groupe immuno-écologie du REID, Montpellier, France.
Bichet C. (2011) Choix de partenaire et insularité, étude chez le moineau domestique. Forum des Jeunes Chercheurs, Dijon, France. Prix de la meilleure présentation orale
Bichet C. (2010) Inhibition expérimentale de la production d’oxyde nitrique lors d’une infection par Plasmodium chez le canari domestique (Serinus canaria). Réunion du groupe immuno-écologie du REID, Montpellier, France.
Bichet C., Dunoyer L., Penn D., Moodley Y., Cellier-Holzem E., Sorci G. (2012) Preference for genetically similar mates in an island population of house sparrows (Passer domesticus). Colloque Petit Pois Déridé, Avignon, France. Prix du meilleur poster. pdf
Bichet C., Potts N., Kaufman J., Guitton E., Chaumeil T., Sorci G. (2011) MHC haplotypes and malaria infection in chicken. Conférence Jacques Monod, Roscoff, France. Présentation poster.
Bichet C. (2012) Ecologie évolutive de la malaria aviaire : Effets des caractéristiques de l’hôte et de l’environnement. Soutenue le 18 décembre 2012, Université de Bourgogne, Dijon, France. pdf
Bichet C. (2012) Insularité et choix de partenaire chez le moineau domestique. Association GNUB, Dijon, France. Séminaire
Bichet C. (2012) Des îles, des nains et des géants. Plume! n°16. Article. pdf
Bichet C. (2012) Modèle Biologique I love you. Plume! n°16. Article. pdf
Bichet C. (2011) Etude de l’insularité chez le moineau domestique LPO Côte d’Or, Dijon, France. Séminaire
Bichet C., Sorci G., Garnier S. (2010) Diversité génétique au sein et entre populations. Alauda, 78(4): 279-288. pdf