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

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