Université de Rennes I


















Joan van Baaren, PhD
Université de Rennes I
Avenue du Général Leclerc
35042 Rennes Cedex, France
Tel: (33) 2 23 23 50 27
Fax: (33) 2 23 23 50 26













Key words : climate change, behavioural ecology of insect parasitoids, landscape ecology, integrative ecology, thermal stresses, life history traits, host-parasitoid interactions, interspecific competition, adaptation.


ANR LANDSCAPHID (2010-2013): Influence of landscape on aphids crop pests and their natural control. Application to ecological engineering for pest management. Responsible: Manuel Plantegenest (UMR BIO3P).

To test whether agricultural landscape features may act as landscape suppressiveness against pests, several hypotheses must be tested: (1) landscape structure and composition should directly influence pest population dynamics, through niche saturation, dispersal barriers, spatial habitat dilution or interferences in host plant chemical signal; (2) the landscape suppressiveness should be enhanced through factors favoring natural enemies population dynamics, such as overwinter refuges, floral resources, dispersal corridors. Identifying landscape factors reducing the frequency and the intensity of pest outbreaks or increasing the efficiency of their natural control is the main goals of this project. However, antagonisms between these landscape factors may also be possible, notably through the interactions occurring at the community level: therefore, a study of the entire community at the landscape level is necessary.
Landscaphid aims at (i) addressing whether landscape suppressiveness hypothesis is valid, by identifying the landscape factors favoring or limiting pest risk and biological control; and (ii) understanding the functioning of this suppressiveness, by researching the ecological processes involved at all ecological levels (from genes to community). By integrating all this information, we will finally (iii) propose landscape management tools to support the agricultural landscape suppressiveness.

ANR CLIMEVOL (2009-2012) Climate change and Evolution of host-parasitoid interactions: from molecules to communities. Responsible: Joan van Baaren

This project will be the first to document the consequences of an invading parasitoid species for an insect community. It combines an ecological approach with three trophic levels (hosts, parasitoids & endosymbionts) with an evolutionary ecological and genetic approach to study the changes in a community in response to climate change and makes use of an already well-studied cline to compare local communities that differ in the length of their history of invasion by a warm-adapted species. We will not only be able to describe changes in community structure, but also to analyse and quantify the ways species adapt to the new situation. The latter is crucial to predict long-term evolutionary changes of climate change and is often neglected in studies on the consequences of climate change. We will use the model system of fruit-inhabiting Drosophila and their larval parasitoids and make use of a unique situation: the well-documented invasion from the south of L.boulardi, a species of African origin, in the Rhône valley and its associated changes in the invaded communities. The Drosophila-parasitoid model is the only one that exists for which detailed knowledge is available on the genetics of virulence in the parasitoids and resistance in the hosts, and for which detailed studies on life history evolution, on patch time allocation and host species selection have been published. Moreover, they have been frequently used as a model for the study of Wolbachia-endosymbionts. We will study how individual hosts and parasitoids respond to different temperatures by phenotypic plastic responses. We will measure the responses on a range of life history traits and on foraging behaviour, using the results to show how life history trade-offs change with temperature. We will use these data to predict short-term changes in population dynamics of the species, and how this will affect the relative abundance of species in the community. Finally we will use these data to construct models on adaptive dynamics, to study long-term evolutionary changes in the community as a consequence of climatic change. By comparing populations with a different length of history of invasion by L.boulardi, sampled along a south - north cline in the Rhône valley, we will be able to document the changes that have occurred over time. This will allow us to test our models. It will also allow us to document the changes that have occurred in life-history traits, in metabolic rates, in host selection behaviour, in patch time allocation and in superparasitism, in the frequency of Wolbachia infection and in virulence of parasitoids and resistance of hosts. The latter genetic changes will be documented on the level of genes as far as these have been identified and we will continue to unravel the underlying genetics of the arms-races between Drosophila-hosts and their parasitoids. Our integrated approach allows us to understand the changes that occur in the community based on the genetic, physiological and behavioural mechanisms. The results of our study, from theoretical models to molecular genetics can - to a certain extent - be applied to other host-parasitoid systems and be used to understand changes in natural and biological control of herbivorous insects. Our programme is is an ambitious one, unique in its integrative approach. The complementarity of the expertise of the participating groups makes it feasible.

Marie Curie Chair (2006-2009): Responsible: Joan van Baaren

The chair holder is the Prof. van Alphen (Univ- Leiden, The Netherlands) who came at the UMR ECOBIO for 3 years. The research project concerned the fact that modern global change at regional scales is predicted to alter species distributions, life histories, community composition, and ecosystem function. Concerning the effect of the climate, in ecosystems, tritrophic interactions (plants-herbivorous insects- natural enemies) result from long co-evolved processes under well-defined climatic conditions. Climate change will influence the biology of the interacting species and the stability of these systems. Within this framework, the present project, based on two food-web model (wheat, related pests (aphids) and their parasitoids and larval parasitoids of Drosophila and their Drosophila hosts) aimed to do:
(1) A comparison of closely related parasitoid species and their host originating from different climatic zones
(2) A comparison of life-history traits in populations of a particular parasitoid species and its host collected along a climatic gradient in Europe

Reviewer for:"Entomologia Experimentalis et Applicata", "The Canadian Entomologist", "Biological control", "Biocontrol", "Proceedings of the Academy of Natural Science of Philadelphia", "Journal of Economical Entomology", "Naturwissenschaften", «Behavioural Ecology and Sociobiology », "Ethology", "Animal Behaviour", "Behavioral Ecology", "Journal of Insect Science", "Micron", "Journal of Apicultural Research", "Environmental Entomology", "Journal of Insect Behaviour", "Animal Biology", "Oecologia", "Ecological Entomology", "Frontiers in Zoology", Aggressive behaviour, International Journal of Pest Management, Journal of Applied Entomology, Plos One.












1. van Baaren, J., Pierre, J.S. & Nénon, J.P. 1993. Analysis of oviposition behaviour in the parasitoid Epidinocarsis lopezi (Hymenoptera : Encyrtidae) : comparison of flow charts on factorial maps. Entomophaga, 38 (2), 207-218. (IF: 0,69).


2. van Baaren, J. & Nénon, J.P. 1994. Factors involved in host discrimination by Epidinocarsis lopezi and Leptomastix dactylopii (Hymenoptera : Encyrtidae). Journal of Applied Entomology, 118, 76-83. (IF: 1,11).


3. van Baaren, J., Boivin, G. & Nénon, J.P. 1994. Intra- and interspecific host-discrimination in two closely related egg parasitoids. Oecologia, 100, 325-330. (IF: 3,00).


4. van Baaren, J., Boivin, G. & Nénon, J.P. 1995. Intraspecific hyperparasitism in a primery Hymenopteran parasitoid. Behavioral Ecology and Sociobiology, 36, 237-242. (IF: 2,91).


5. van Baaren, J., Boivin, G. & Nénon, J.P. 1995. Oviposition behaviour of Anaphes victus and Anaphes listronoti (Hymenoptera : Mymaridae), egg parasitoids of Listronotus oregonensis (Coleoptera : Curculionidae). Journal of Insect Behaviour, 8, 671-686. (IF: 1,17).


6. Nénon, J.P., Boivin, G., Le Lannic, J. & van Baaren J. 1995. Functional morphology of the mymariform and sacciform larvae of the egg parasitoid Anaphes victus (Hymenoptera : Mymaridae). Canadian Journal of Zoology, 73, 996-1000. (IF: 1,38).


7. van Baaren, J., Barbier, R. & Nénon, J.P. 1996. Females antennal sensilla of Epidinocarsis lopezi and Leptomastix dactylopii (Hymenoptera: Encyrtidae), parasitoids of pseudococcid mealybugs. Canadian Journal of Zoology, 74, 710-720. (IF: 1,38).


8. van Baaren, J. & Nénon, J.P. 1996. Host location and discrimination mediated through olfactive stimuli in two species of Encyrtidae. Entomologia experimentalis et applicata, 81, 61-69. (IF: 1,28).


9. van Baaren, J. & Nénon, J.P. 1996. Intraspecific larval competition in two solitary parasitoids, Apoanagyrus (Epidinocarsis) lopezi and Leptomastix dactylopii. Entomologia experimentalis et applicata, 81, 325-333. (IF: 1,28).


10. van Baaren, J., Boivin, G., Le Lannic, J.& Nénon, J.P. 1997. The male and female first instar larvae of Anaphes victus and A. listronoti (Hymenoptera: Mymaridae). Zoomorphology, 117, 189-197. (IF: 1).


11. van Baaren, J. & Boivin, G. 1998. Learning affects the host discrimination behavior in Anaphes victus (Hym: Mymaridae). Behavioral Ecology and Sociobiology, 42, 9-16. (IF: 2,91).


12. van Baaren, J. & Boivin, G. 1998. Genotypic and kin discrimination in a solitary Hymenopterous parasitoid: implications on speciation. Evolutionary ecology, 12, 523-534. (IF: 3,44).


13. van Baaren, J., Landry, B.L. & Boivin, G. 1999. Sex allocation and larval competition in a superparasitizing solitary egg parasitoid: competing strategies for an optimal sex ratio. Functional Ecology 13, 66-71. (IF: 3,69).


14. van Baaren J., Boivin G., Le Lannic J. & Nénon J.P. 1999. Comparison of antennal sensilla of Anaphes victus and A. listronoti (Hymenoptera: Mymaridae), egg-parasitoids of Curculionidae. Zoomorphology 119, 1-8. (IF: 1).


15. van Baaren J 1999. Comparison of interattraction in a lineage of Zetoborinae cockroaches
Annales de la Société Entomologique de France 35, 190-196  (IF=0,93)  


16. Boivin, G. & van Baaren, J. 2000. The role of larval aggression and mobility in the transition between solitary and gregarious development in parasitoid wasps. Ecology letters 3 (6), 469-474. (IF: 9,39).

Cet article a fait l'objet d'un commentaire dans TREE 16, 7-9 (2001) par JJ Pexton & PJ Mayhew "Immobility: the key to family harmony?"



17. van Baaren J., Deleporte P. 2001. Comparison of gregariousness in larvae and adults of four species of Zetoborinae cockroaches. Entomologia Experimentalis et Applicata 99, 113-119. (IF: 1,28).


18. van Baaren J., Deleporte P, Grandcolas P., Biquand V. & Pierre J.S. 2002. Measurement for solitariness and gregarism: analysing spacing, attraction and interactions in four species of Zetoborinae (Blattaria). Ethology 108, 697-712. (IF: 1,98).


19. van Baaren J., Deleporte P & Grandcolas P. 2002. Cockroaches in Icteridae bird nests in French Guyana. Amazoniana 17, 243-248. (IF: 0,14).


20. Pierre, J.S., van Baaren, J. & Boivin G. 2003. Do parasitoids achieve a sequencial decisional sampling? Behavioral Ecology and Sociobiology 54: 147-155. (IF: 2,91).


21. van Baaren J., Bonhomme A.S., Deleporte P. & Pierre J.S. 2003. Behaviours promoting grouping or dispersal of mother and neonates in ovoviviparous cockroaches. Insectes sociaux, 50, 45-53. (IF: 1,01).


22. van Baaren J., Eckstein E., Deleporte P., Biquand V., Le Rouzo T. & Pierre J.S., 2003. Social interactions during development in the ovoviviparous cockroaches Schultesia lampyridiformis. Behaviour, 140(6), 721-738. (IF: 1,56).


23. van Baaren J., Héterier V., Hance T., Krespi L., Cortesero A.M., Poinsot D., Le Ralec A., Outreman Y.  2004. Playing the hare or the tortoise in parasitoids: could different oviposition strategies be involved in host partitioning in two Aphidius species? Ethology, Ecology & Evolution, 16 (3), 231-242. (IF: 0,94).


24. Grandcolas P., Pellens R., Deleporte P., van Baaren J. 2004. The poverty of phylogeny, the poverty of taxonomy, the poverty of natural history,... their richness altogether as shown by a case study on cockroaches. Cladistics, 20 (6): 596-596 (IF: 3,51)


25. van Baaren J., Outreman Y., Boivin G. 2005. Effect of low temperature exposure on oviposition behaviour and patch exploitation strategy in parasitic wasps. Animal Behaviour, 70, 153-163. (IF: 2,82).

26. van Baaren J., Outreman Y. & Boivin G. 2005. Patch exploitation strategy by an egg parasitoid in constant or variable environement. Ecological Entomology, 30, 1-8. (IF: 1,910).

27. Roux O., van Baaren J. Gers C., Arvanitakis L., Legal L. 2005. Antennal structure and oviposition behavior of the Plutella xylostella specialist parasitoid: Cotesia plutellae. Microscopy Research and Technique, 68, 36-44. (IF: 1,88).


28. Bourdais D., Vernon P., Krespi L., Le Lannic J., & van Baaren J. 2006. Antennal structure of male and female Aphidius rhopalosiphi DeStefani-Peres (Hymenoptera : Braconidae) : description and morphological alterations after cold storage or heat exposure. Microscopy Research and Technique, 69:1005-1013 (IF: 1,88).

29. Hance T., van Baaren J., Vernon, P., Boivin G., 2007. Impact of temperature extremes on parasitoids in a climate change perspective. Annual Review of Entomology, 52, 107-126 (IF=11,91).


30. van Baaren J., Deleporte P., Vimard A., Biquand V. & Pierre J.S. 2007. Aggressive interactions in a cockroach: a relic of a parent-offspring conflict? Aggressive behavior, 33, 1-10 (IF=2,05).


31. Amice G., Vernon P., Outreman Y., van Alphen J. & van Baaren  J. 2008. Variability in responses to thermal stress in parasitoids. Ecological Entomology, 33, 701-708  (IF: 1,91).


32. Le Lann C., Outreman Y., van Alphen J., Krespi L., Pierre J.S. & van Baaren J. 2008. Do past experience and competitive ability influence foraging strategies of parasitoids under interspecific competition. Ecological Entomology, 33, 691-700. (IF: 1,91).


33. van Baaren J, Le Lann C, Pichenot J, Pierre JS, Krespi K, Outreman Y. 2009. How could host discrimination abilities influence the structure of a parasitoid community. Bulletin of entomological research 99, 299-306. IF: 1.415.

34. Roux O., Le Lann C., van Alphen J.J.M. and van Baaren J. 2010. How does heat shock affect the life history traits of adults and progeny of the aphid parasitoid Aphidius avenae (Hymenoptera: Aphidiidae)? Bulletin of Entomological Research, 27: 1-7. IF: 1.415.

35. Le Ralec A., Anselme C., Outreman Y., Poirié M., van Baaren J., Le Lann C., van Alphen J.J.M. 2010. Evolutionary ecology of the interactions between aphids and their parasitoids. Comptes Rendus Biologies, 333(6-7), 554-565. IF: 1.454

36 Ismail M, Vernon P, Hance T and van Baaren J.. 2010. Physiological Costs of Cold Exposure on the Parasitoid Aphidius ervi, without selection pressure and under constant or fluctuating temperatures. Biocontrol. 55, 729-740. IF = 1,91.


37. Moiroux J, Le Lann C, Seyahooei MA, Vernon P, Pierre JS, van Baaren J and van Alphen JJM. 2010. Local adaptations of life history traits of a Drosophila parasitoid, Leptopilina boulardi: does climate drive evolution? Ecological Entomology.35, 727-736.  IF=1,91.


38. Le Lann C, Roux O, Serain N, van Alphen JJM, Vernon P and van Baaren J. 2011. Thermal tolerance of sympatric hymenopteran parasitoid species: does it match seasonal activity? Physiological Entomology. 36, 21-28 IF = 1,53.


39. Le Lann C., Outreman Y., van Alphen J.J.M. and van Baaren J. 2011. First in, last out: asymmetric competition influences patch exploitation of a parasitoid. Behavioral Ecology. 22(1),101-107. IF=3,22.


40. Le Lann C., Wardziak T., van Baaren J., van Alphen J.J.M. 2011. Plasticity in metabolic rates and life history traits affects foraging behaviour in a parasitic wasp. Functional ecology. 25, 641-651.  IF = 3,69


41. Denis D, Pierre JS, van Baaren J & van Alphen JJM. 2011. How sudden temperature increase events and habitat quality affect parasitoids lifetime reproductive success. Ecological modelling 222 (9) 1604-1613. IF=2,17.


42. Louâpre P, van Baaren J, Pierre JS and van Alphen JJM. 2011. Foraging in a patchy resource: Parasitic wasps assess relative patch quality and modify their intra-patch behavior accordingly. Behavioral Ecology. doi: 10.1093/beheco/arr090.


43. Le Lann C , Visser B, van Baaren J, van Alphen JJM,  Ellers J. 2011. Comparing resource exploitation and allocation of two closely related aphid parasitoids sharing the same host. online. Evolutionary Ecology. DOI 10.1007/s10682-011-9498-2.


44. Josso C., Moiroux J., Vernon P., Van Baaren J., Van Alphen J.J.M.. Influence of temperature and parasitism by Asobara tabida on larval pupation behaviour in two Drosophila species. In press. Naturwissenshaften.


45. Bourdais D, Krespi L, Vernon P and van Baaren J..Behavioural consequences of cold exposure on males and females of a parasitic wasp. In press. Biological Control.






Van Baaren J., Boivin G., Bourdais D. & Roux O. 2007. Antennal sensilla of hymenopteran parasitic wasps: variations linked to host exploitation behavior. In: Antonio Mendez Vilas, Jesus Diaz Alvarez (eds), Modern research and educational topics in microscopy, pp. 345-352. Elsevier.


Van Baaren J., Le Lann C & van Alphen J. 2010. Consequences of Climate Change for Aphid-Based Multi-trophic Systems. In : P. Kindlmann, A.F.G. Dixon, J.P. Michaud (eds.), Aphid Biodiversity under Environmental Change. Springer Science 2010. DOI 10.1007/978-90-481-8601-3, ISBN: 978-90-481-8600-6

van Baaren J., Boivin G., Outreman Y. 2006. Deleterious effects of low temperature exposure on learning capacities in a parasitoid. Int J Comp Psychol, 19, 368-385