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de MAZANCOURT Claire

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Claire de Mazancourt, Centre for Biodiversity Theory and Modelling







My work aims at predicting the effects of biodiversity loss and other global changes on ecosystem functioning. I generate theoretical predictions of ecosystem functioning depending on component species, their diversity, their ecological interactions, as well as their evolutionary dynamics.

BiodiversityStability
With global changes, ecosystem functioning might become less predictable. Several experiments have shown that biodiversity enhances the temporal stability of vegetation biomass. Stability is a key aspect of ecosystem services. I am developing a theory that fosters our understanding of the mechanisms through which biodiversity stabilises communities, to predict community stability from measurable traits of its component species, and that can be applied to experimental and observational data.

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Figure : my theory can be applied to data from large biodiversity experiments such as David Tilman’s in Cedar Creek (Minnesota, USA).

Evolution and ecosystem functioning
I am interested in the reciprocal effects of evolutionary dynamics and species interactions on ecosystem functioning. For example, rapid evolutionary dynamics of a predator might enable coexistence of several preys ; competitors might slow down adaptation to environmental change.

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Figure : Integration of sub-disciplines in ecology is a key feature of the theoretical ecology developed in the Centre.

Mutualism theory.
Where do mutualisms come from, how do they evolve ?
Do they evolve from exploitative interactions ? Could some plants benefit from herbivory ? What is a mutualism ? In any mutualism, I argue that a benefit can simply be due to evolved dependence, the adaptation to a partner. The organism has evolved a dependence so that it is not able to function without its partner anymore. This could be the case for some plants adapted to herbivory, and is likely to be the case in any mutualistic interaction with a long evolutionary history.
Could some mutualism come from competitive interactions ? I developed a theory of the evolution of a trading mutualism for two essential resources, between two competitors, that could apply to plants and their mycorrhizae.

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Figure : did the trading mutualism between plants and their mycorrhizae evolve from a competitive interaction ?

Nutrient cycling and primary production : the Input-Output Theory.
I developed a new theory of the effect of nutrient cycling on primary production : the Input-Output theory. It defines the conditions for herbivores to increase primary production through nutrient cycling, and can be applied to litter quality.

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Figure : Simplified ecosystem model representing the cycle of a limiting nutrient such as nitrogen.

Evolutionary dynamics depending on trade-off geometry.
An organism cannot do everything at the same time. This is the basics of trade-offs that enable biodiversity. Trade-offs are really difficult to measure and their shapes are often unknown. I developed a method to evaluate all possible outcomes of evolutionary dynamics for all possible trade-off shapes, when there is a trade-off between two continuous traits.

de Mazancourt, C., and Dieckmann, U. 2004. Trade-off geometries and frequency-dependent selection. American Naturalist. 164 : 765-778.

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Mathematica file with codes for figure 3C and 4C of de Mazancourt and Dieckmann (2004). The code was written to be easily used with other equations.



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Figure : The evolutionary landscape defines all possible evolutionary outcomes in the space of two continuous traits, where the two traits are constrained by a trade-off of unknown shape.

Publications in peer-reviewed journals  :

  • 28. de Mazancourt, C. ; Isbell, F. ; Larocque, A. ; Berendse, F. ; De Luca, E. ; Grace, J. ; Haegeman, B. ; Polley, H. ; Roscher, C. ; Schmid, B. ; Tilman, D. ; van Ruijven, J. ; Weigelt, A. ; Wilsey, B. ; Loreau, M.. (in press). Predicting ecosystem stability from community composition and biodiversity. Ecology Letters.
  • 27. Loreau, M. and C. de Mazancourt (in press). Biodiversity and ecosystem stability : a synthesis of underlying mechanisms. Ecology Letters.
  • 26. Osmond, MM, and C. de Mazancourt. 2012. How competition affects evolutionary rescue. Phil Trans R Soc B 368 : 20120085.
  • 25. Calcagno, V., E. Demoinet, K. Gollner, L. Guidi, D.Ruths, and C. de Mazancourt. 2012. Flows of research manuscripts among scientific journals reveal hidden submission patterns. Science 176:198-211.
  • 24. de Mazancourt, C., and M. W. Schwartz. 2012. Starve a competitor : evolution of luxury consumption as a competitive strategy. Theoretical Ecology 5 : 37-49.
  • 23. Calcagno, V., M. Dubosclard, and C. de Mazancourt. 2010. Rapid Exploiter-Victim Coevolution : The Race Is Not Always to the Swift. American Naturalist 176:198-211.
  • 22. Calcagno, V., and C. de Mazancourt. 2010. glmulti : An R Package for Easy Automated Model Selection with (Generalized) Linear Models. Journal of Statistical Software 34:1-29.
  • 21. de Mazancourt, C., and M. W. Schwartz. 2010. A resource ratio theory of cooperation. Ecology Letters 13:349-359.
  • 20. Everard K.A., Seabloom E.W., Harpole W.S. and de Mazancourt C. 2010. Plant water use affects competition for nitrogen : why drought favors invasive species in California. American Naturalist 175:85-97.
  • 19. Perring M.P., Edwards G. and de Mazancourt C. 2009. Removing phosphorus from ecosystems through nitrogen fertilization and cutting with removal of biomass. Ecosystems 105:1971-1976.
  • 18. Loreau, M., and C. de Mazancourt. 2008. Species synchrony and its drivers : Neutral and nonneutral community dynamics in fluctuating environments. American Naturalist 172 :E48-E66.
  • 17. Olofsson, J., C. de Mazancourt, and M. J. Crawley. 2008. Spatial heterogeneity and plant species richness at different spatial scales under rabbit grazing. Oecologia 156:825-834.
  • 16. Urban, M. C., M. A. Leibold, P. Amarasekare, L. De Meester, R. Gomulkiewicz, M. E. Hochberg, C. A. Klausmeier, N. Loeuille, C. de Mazancourt, J. Norberg, J. H. Pantel, S. Y. Strauss, M. Vellend, and M. J. Wade. 2008. The evolutionary ecology of metacommunities. Trends in Ecology & Evolution 23:311-317.
  • 15. de Mazancourt, C., Johnson, E., Barraclough, T. 2008. Biodiversity inhibits species’ evolutionary responses to changing environments. Ecology Letters, 11 : 380-388.
  • 14. Perring, M. P., L. O. Hedin, S. A. Levin, M. McGroddy, and C. de Mazancourt. 2008. Increased plant growth from nitrogen addition should conserve phosphorus in terrestrial ecosystems. Proceedings of the National Academy of Sciences of the United States of America 105:1971-1976.
  • 13. Olofsson, J., de Mazancourt, C. and Crawley, M.J. 2007. Contrasting effects of herbivore exclusion on N availability and primary production at different time-scales. Oecologia, 150 : 582-589.
  • 12. Clark, B., Hartley, S.E., Nash Sudling, K., de Mazancourt, C. 2005. The effect of recycling on plant competitive hierarchies. American Naturalist. 165 : 609-622.
  • 11. de Mazancourt, C., Loreau, M., & Dieckmann, U. 2005. Understanding mutualism when there is adaptation to the partner. Journal of Ecology, 93 : 305-314.
  • 10. Crawley, M.J., Johnston, A.E., Silvertown, J., Dodd, M., de Mazancourt, C., Heard, M.S., Henman, D.F., & Edwards, G.R. 2005. Determinants of species richness in the park grass experiment. American Naturalist, 165 : 179-192.
  • 9. de Mazancourt, C., and Dieckmann, U. 2004. Trade-off geometries and frequency-dependent selection. American Naturalist. 164 : 765-778.
  • 8. Voituron, Y., Mouquet, N., Clobert, J. and de Mazancourt, C. 2002. To freeze or not to freeze ? an evolutionary perspective on the cold hardiness strategies of overwintering ectotherms. American Naturalist, 160 : 255-270.
  • 7. de Mazancourt, C. 2001. The unified neutral theory of biodiversity and biogeography by Hubbell SP. Science 293 : 1772-1772. (Book review)
  • 6. de Mazancourt, C., Loreau, M, and Dieckmann, U. 2001. Can the evolution of plant defense lead to plant-herbivore mutualism ? American Naturalist, 158 : 109-123.
  • 5. de Mazancourt, C., and Loreau, M. 2000. Effect of herbivory and plant species replacement on primary production. American Naturalist, 155 : 735-754.
  • 4. de Mazancourt, C., and Loreau, M. 2000. Grazing optimization, nutrient cycling, and spatial interaction of plant herbivore interactions : should a palatable plant evolve ? Evolution, 54 : 81-92.
  • 3. Loreau, M, and de Mazancourt, C. 1999. Should plants in resource-poor environments invest more in antiherbivore defence ? Oikos, 87 : 195-200.
  • 2. de Mazancourt, C., Loreau, M., and Abbadie, L. 1999. Grazing optimization and nutrient cycling : Potential impact of large herbivores in a savanna ecosystem. Ecological Applications, 9 : 784-797.
  • 1. de Mazancourt, C., Loreau, M., and Abbadie, L. 1998. Grazing optimization and nutrient cycling : When do herbivores enhance primary production ? Ecology 79 : 2242-2252.

 

Other publications :


Loreau, M., de Mazancourt, C., and Holt, R.D. 2004. Ecosystem evolution and conservation. in Evolutionary Conservation Biology. Ferrière, R., Dieckmann, U. and Couvet, D., eds. Cambridge Studies in Adaptive Dynamics, IIASA and Cambridge University Press, Cambridge, pp 327-343.

Abdallah, A., de Mazancourt, C., Elinge M. M., Graw B., Grzesiuk M., Henson K., Kamoga M., Kolodziejska I., Kristersson M., Kuria A., Leonhartsberger P., Matemba R. B., Merl M., Moss B., Minto C., Murfitt E., Musila S. N., Ndayishiniye J., Nuhu D, Oduro D. J., Provvedi S., Rasoma R. V., Ratsoavina F., Trevelyan R., Tumanye N., Ujoah V. N., Van De Wiel G., Wagner T., Waylen K., and Yonas M. 2004. Comparative studies on the structure of an upland African stream ecosystem. Freshwater Forum 21 : 27-47.