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Project ongoing since 2018


Causes and consequences of functional rarity from local to global scales 


Rarity has always fascinated conservation and evolutionary biologists with the goal to uncover species characteristics causing extinction risk. Recently, some results suggest that rare species may over-contribute to the diversity of traits within communities thus supporting irreplaceable roles while others show that rare species are functionally redundant with common species. 


Beyond the rarity of species, the rarity of functions played by species, coined as functional rarity, is thus key to understand the impact of biodiversity decline on ecosystem functioning. However, functional rarity still lacks a clear definition and a quantitative framework while its emergence and maintenance within communities is largely unknown. 


The aim of the FREE working group is to advance the concept of functional rarity and examine the causes and consequences of functional rarity from local to global scales. We will first analyze the distribution of functional rarity in communities, regions, biomes and at a global scale using a cross-taxonomic group comparative approach (plants, microbes, mammals, birds, fishes) using an identified set of inter-operable databases. Next, we will explore the theoretical causes of the maintenance of functional rarity in communities using simulations. Finally, we will evaluate the theoretical consequences of functional rarity loss on ecosystem functioning and quantify them using a database of biodiversity-ecosystem functioning experiments in plants. 




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FREE brings together specialists in community ecology, macro-ecology, biogeography, functional ecology, microbial ecology and phylogeny. 



Cyrille VIOLLE – CEFE-CNRS (France); Caroline TUCKER – University of Colorado (USA).



Nicolas LOISEAU – CEFE-CNRS (France)



Adam ALGAR – University of Nottingham (UK); Arnaud AUBER – IFREMER Boulogne-sur-mer (France); Marc CADOTTE – University of Toronto, (Canada); Pierre DENELLE -CNRS (France); Brian ENQUIST – University of Arizona (USA); Noah FIERER – University of Colorado (USA); Matthias GRENIE – CNRS (France); Gaurav KANDLIKAR – University of California (USA); Christopher KLAUSMEIER – Michigan State University (USA); Nathan KRAFT, University of Maryland (USA); Sébastien LAVERGNE -Université de Grenoble (France); Helena LITCHMAN – Michigan State University (USA); Anthony MAIRE – EDF (France); Brian MAITNER – University of Arizona (USA); Camille MARTINEZ –  Grenoble University (France); Brian MCGILL – University of Maine (USA); Matthew MCLEAN – Ifremer (France); David MOUILLOT – University of Montpellier (France); Nicolas MOUQUET – CNRS Montpellier (France); François MUNOZ – Grenoble University (France); Juliette MURGIER – Ifremer (France); Annette OSTLING -University of Michigan (USA); Wilfried THUILLER – CNRS Grenoble (France); Sébastien VILLEGIER – CNRS (France); Lucie ZINGER – University of Paul Sabatier (France).


[09] Thuiller W, Gravel D, Ficetola GF, Lavergne S, Münkemüller T, Pollock LJ, Zimmermann NE & Mazel F (2020) Productivity begets less phylogenetic diversity but higher uniqueness than expected. Journal of Biogeography, 47, 44–58. doi: 10.1111/jbi.13630.


[08] Denelle P, Violle C & Munoz F (2019) Distinguishing the signatures of local environmental filtering and regional trait range limits in the study of trait–environment relationships. Oikos, 128, 960–971. doi: 10.1111/oik.05851.


[07] McLean M, Auber A, Graham NAJ, Houk P, Villéger S, Violle C, Thuiller W, Wilson SK & Mouillot D (2019) Trait structure and redundancy determine sensitivity to disturbance in marine fish communities. Global Change Biology, 25, 3424–3437. doi: 10.1111/gcb.14662.


[06] Echeverría-Londoño S, Enquist BJ, Neves DM, Violle C, Boyle B, Kraft NJB, Maitner BS, McGill BJ, Peet RK, Sandel B, Smith SA, Svenning J-C, Wiser SK & Kerkhoff AJ (2018) Plant functional diversity and the biogeography of biomes in North and South America. Frontiers in Ecology and Evolution, 6, 219. doi: 10.3389/fevo.2018.00219.


[05] Grenié M, Mouillot D, Villéger S, Denelle P, Tucker CM, Munoz F & Violle C (2018) Functional rarity of coral reef fishes at the global scale: Hotspots and challenges for conservation. Biological Conservation, 226, 288–299. doi: 10.1016/j.biocon.2018.08.011.


[04] Blonder B, Morrow CB, Maitner BS, Harris DJ, Lamanna C, Violle C, Enquist BJ & Kerkhoff AJ (2017) New approaches for delineating n-dimensional hypervolumes. Methods in Ecology and Evolution, 9, 305–319. doi: 10.1111/2041-210X.12865.


[03] Grenié M, Denelle P, Tucker CM, Munoz F & Violle C (2017) funrar: An R package to characterize functional rarity. Diversity and Distributions, 23, 1365–1371. doi: 10.1111/ddi.12629.


[02] Violle C, Thuiller W, Mouquet N, Munoz F, Kraft NJB, Cadotte MW, Livingstone SW, Grenié M & Mouillot D (2017) A common toolbox to understand, monitor or manage rarity? A response to Carmona et al. Trends in Ecology & Evolution, 32, 891–893. doi: 10.1016/j.tree.2017.10.001.


[01] Violle C, Thuiller W, Mouquet N, Munoz F, Kraft NJB, Cadotte MW, Livingstone SW & Mouillot D (2017) Functional rarity: The ecology of outliers. Trends in Ecology & Evolution, 32, 356–367. doi: 10.1016/j.tree.2017.02.002.