Research Topic

Functional Rarity

Functional rarity is the concept of rare species that play important ecological roles (Violle et al. 2017). It is a measure of the rarity of the functions performed by species, rather than the rarity of the species themselves. Functional traits are the characteristics of species that determine their ecological roles (including body size, habitat preference, diet, and dispersal ability). Functional diversity is the variety of functional traits present in a community, reflecting the range of ecological roles performed by its species.

Functional rarity is important because it can help us understand the impact of biodiversity loss on ecosystem functioning. Rare species often play important ecological roles that are not performed by other species, and if these species become extinct, the ecosystem may be unable to function properly. In this framework I have initiated and participated in several research projects mainly to address functional rarity and conservation as well as ecosystem functioning. This research has also resulted in producing review papers and integrative approaches.

Functional Rarity & Conservation

  1. Mouquet N., Mahaut L., Thuiller W., Auber A., Casajus N., Enquist B.J., Ga"uz`ere P., Loiseau N., Mouillot D., Munoz F., Vill'eger S., Violle C. (2025). Spatial Insurance of Distinct Ecological Functions. Ecology Letters, doi.org/10.1111/ele.70266

  2. Mahaut L., Loiseau N., Villeger S., Auber A., Hautecoeur C., Maire A., Mellin C., Mouquet N., Stuart-Smith R.D., Violle C., Mouillot D. (2025). Functional diversity shapes the stability of reef fish biomass under global change. Proceedings of the Royal Society B Biological Sciences, doi.org/10.1098/rspb.2025.0252

  3. Loiseau N.*, Mouquet N.*, Casajus N., Grenie M., Gueguen M., Maitner B., Mouillot D., Ostling A., Renaud J., Tucker C.M., Velez L., Thuiller W., Violle C. (2020). Global distribution and conservation status of ecologically rare mammal and bird species. Nature Communications, doi.org/10.1038/s41467-020-18779-w (* These authors contributed equally to this work)

  4. Mouillot D., Bellwood D.R., Baraloto C., Chave J., Galzin R., Harmelin-Vivien M., Kulbicki M., Lavergne S., Lavorel S., Mouquet N., Paine C.E.T., Renaud J., Thuiller W. (2013). Rare Species Support Vulnerable Functions in High-Diversity Ecosystems. PLoS Biology, doi.org/10.1371/journal.pbio.1001569

Functional Rarity & Ecosystem Functioning

  1. Mouquet N., Mahaut L., Thuiller W., Auber A., Casajus N., Enquist B.J., Ga"uz`ere P., Loiseau N., Mouillot D., Munoz F., Vill'eger S., Violle C. (2025). Spatial Insurance of Distinct Ecological Functions. Ecology Letters, doi.org/10.1111/ele.70266

  2. Delalandre L., Gauzere P., Thuiller W., Cadotte M.W., Mouquet N., Mouillot D., Munoz F., Denelle P., Loiseau N., Morin X., Violle C. (2022). Functionally distinct tree species support long-term productivity in extreme environments. Proceedings of the Royal Society B Biological Sciences, doi.org/10.1098/rspb.2021.1694

  3. Auber A., Waldock C., Maire A., Goberville E., Albouy C., Algar A.C., McLean M., Brind'Amour A., Green A.L., Tupper M., Vigliola L., Kaschner K., Kesner-Reyes K., Beger M., Tjiputra J., Toussaint A., Violle C., Mouquet N., Thuiller W., Mouillot D. (2022). A functional vulnerability framework for biodiversity conservation. Nature Communications, doi.org/10.1038/s41467-022-32331-y

Integrative Approaches & Reviews

  1. Munoz F., Klausmeier C.A., Gauzere P., Kandlikar G.S., Litchman E., Mouquet N., Ostling A., Thuiller W., Algar A.C., Auber A., Cadotte M.W., Delalandre L., Denelle P., Enquist B.J., Fortunel C., Grenie M., Loiseau N., Mahaut L., Maire A., Mouillot D., Pimiento C., Violle C., Kraft N.J.B. (2023). The ecological causes of functional distinctiveness in communities. Ecology Letters, doi.org/10.1111/ele.14265

  2. Mouillot D., Loiseau N., Grenie M., Algar A.C., Allegra M., Cadotte M.W., Casajus N., Denelle P., Gueguen M., Maire A., Maitner B., McGill B.J., McLean M., Mouquet N., Munoz F., Thuiller W., Villeger S., Violle C., Auber A. (2021). The dimensionality and structure of species trait spaces. Ecology Letters, doi.org/10.1111/ele.13778

  3. Violle C., Thuiller W., Mouquet N., Munoz F., Kraft N.J.B., Cadotte M.W., Livingstone S.W., Grenie M., Mouillot D. (2017). A Common Toolbox to Understand, Monitor or Manage Rarity? A Response to Carmona et al.. Trends in Ecology & Evolution, doi.org/10.1016/j.tree.2017.10.001

  4. Violle C., Thuiller W., Mouquet N., Munoz F., Kraft N.J.B., Cadotte M.W., Livingstone S.W., Grenie M. and Mouillot D. (2017). Functional Rarity: The Ecology of Outliers. Trends in Ecology and Evolution, 32, 356–367, doi:10.1016/j.tree.2017.02.002

Other topic pages

Aesthetics iconBiodiversity Aesthetics Biodiversity and ecosystem functioning iconBiodiversity & Ecosystem Functioning Biogeography iconBiogeography, Macroecology & Ecophylogenetics Experimental evolution iconExperimental Evolution Functional biogeography iconFunctional Biogeography Metacommunities iconMetacommunities Metaecosystems iconMetaecosystems Nature for Future iconNature for Future Reviews and synthesis iconReviews and Synthesis Trophic biogeography and metaweb iconTrophic Biogeography & Metaweb Biodiful iconBiodiful OutreachOutreach CollaboratorsCollaborators