%0 Journal Article %9 ACL : Articles dans des revues avec comité de lecture répertoriées par l'AERES %A Vergnon, Rémi %A Dulvy, N. K. %A Freckleton, R. P. %T Niches versus neutrality : uncovering the drivers of diversity in a species-rich community %D 2009 %L fdi:010048177 %G ENG %J Ecology Letters %@ 1461-023X %K Biodiversity ; body mass ; coexistence ; competition ; migration ; neutrality ; niche space ; niche-based processes ; species similarity %M ISI:000269742600008 %N 10 %P 1079-1090 %R 10.1111/j.1461-0248.2009.01364.x %U https://www.documentation.ird.fr/hor/fdi:010048177 %> https://www.documentation.ird.fr/intranet/publi/2009/09/010048177.pdf %V 12 %W Horizon (IRD) %X Ecological models suggest that high diversity can be generated by purely niche-based, purely neutral or by a mixture of niche-based and neutral ecological processes. Here, we compare the degree to which four contrasting hypotheses for coexistence, ranging from niche-based to neutral, explain species richness along a body mass niche axis. We derive predictions from these hypotheses and confront them with species body-mass patterns in a highly sampled marine phytoplankton community. We find that these patterns are consistent only with a mechanism that combines niche and neutral processes, such as the emergent neutrality mechanism. In this work, we provide the first empirical evidence that a niche-neutral model can explain niche space occupancy pattern in a natural species-rich community. We suggest this class of model may be a useful hypothesis for the generation and maintenance of species diversity in other size-structured communities. %$ 021 ; 082