center for synthesis
and analysis of biodiversity

A centre created and developed by the FRB


Causes and consequences of functional rarity from local to global scale



Coordinator  : Cyrille Violle, CEFE-CNRS

Postdoctoral student : Nicolas Loiseau

Group members : Adam Algar, University of Nottingham, UK; Arnaud Auber, IFREMER Boulogne-sur-mer, France; Marc Cadotte, University of Toronto, Canada; Noah Fierer, University of Colorado, USA; Nathan Kraft, University of Maryland, USA; Sébastien Lavergne, Université de Grenoble, France; Brian McGill, University of Maine, USA; David Mouillot, University of Montpellier, France; Nicolas Mouquet, CNRS Montpellier, France; François Munoz, University of Montpellier, France; Annette Ostling, University of Michigan, USA; Wilfried Thuiller, CNRS Grenoble, France; Caroline Tucker, University of Colorado, USA; Lucie Zinger, University of Paul Sabatier, Toulouse, France.



The importance of rare species is well recognised in law (e.g. IUCN Red list), but their ecological importance is poorly understood. Beyond the rarity of a species, the rarity of the functions played by a species (functional rarity) is key to understanding the impact of biodiversity decline on ecosystem function. 

Rarity has always fascinated conservation and evolutionary biologists with the goal of discovering the characteristics of species that are at risk of extinction. Recently, some results suggest that rare species make a high contribution to the diversity of traits within communities, and they have irreplaceable roles, while other results show that rare species are functionally redundant.

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

The aim of the FREE working group is to explore the concept of functional rarity and examine the causes and consequences of functional rarity at local to global scales. We will first analyse the distribution of functional rarity at community, regional, biome and global scales using a cross-taxonomic comparative approach (plants, microbes, mammals, birds, fishes) and 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.

link to publications


Global Evaluation of the Impacts of Storms on freshwater Habitat and structure of phytoplankton Assemblages


Coordinator: Orlane Anneville - INRA (France)

Co-leaders: Jason Stockwell - University of Vermont (USA) ; Vijay Patel - US Geological Survey, Alaska (USA)

Postdoctoral fellow: Jonathan Doubek - University of Vermont (USA)

Participants: Gaël Dur - Shizuoka University (Japan); Sami Souissi - University of Lille 1 (France); François Schmitt - CNRS (France); Patrick Venail - Institut Forel, University of Geneva (Switzerland); Emily Nodine - University of Vermont (USA); Nico Salmaso - IASMA (Italie); Chih-hao Hsieh - National Taiwan University (Taiwan); Marc Lajeunesse - University of South Florida (USA); Rita Adrian - Leibniz-Institute of Freshwater Ecology and Inland Fisheries (Germany); Dietmar Straile - University of Konstanz (Germany); James Rusak - Dorset Environmental Science Centre (Canada); Aleksandra Lewandowska - Institute for Chemistry and Biology of the Marine Environment (Germany).

The GEISHA project brings together experts in theoretical ecology, aquatic ecology, limnology, biodiversity, plankton taxonomy impact of extreme events, climate change, statistical analysis, series-temporal meta-analysis, Bayesian approaches, turbulence and nonlinear variability analysis, and multivariate modeling.

GEISHA is cofinanced by the John Wesley Powell Center for analysis and synthesis, Colorado, USA.PowellCenter emblem 11

Learn more about the project on YouTube:

Antarctic ice_web_18

Retrospective Analysis of Antarctic Tracking data (RAATD) to identify areas of ecological significance in the Antarctic



Project leader: Yan Ropert-Coudert, Centre d'Etudes biologique de Chizé (CNRS - Université La Rochelle), France (

Postdoctoral member: Ryan Reisinger.

Participants : Horst Bornemann, Alfred Wegener Institute, Helmholtz Centre for Polar and Marine Research, Germany ; Jean-Benoît Charrassin, LOCEAN, Muséum national d’Histoire naturelle, Université Pierre et Marie Curie, France; Bruno Danis, Université Libre de Bruxelles, Belgium; Mark Hindell, University of Tasmania, Australia ; Luis Huckstadt, University of California, Santa Cruz, USA ; Ian Jonsen, Macquarie University, Australia; Ben Raymond, Australian Antarctic Division, Australia ; Philip Trathan, British Antarctic Survey the United Kingdom; Anton Van de Putte, Royal Belgian Institute for Natural Science, Belgium ; David Thompson, National Institute of Water and Atmospheric Research Ltd., New Zealand ; Leigh Torres, Oregon State University, USA.