Connolly, S. R., MacNeil, M. A., Caley, M. J., Knowlton, N., Cripps, E., Hisano, M., Thibaut, L. M., Bhattacharya, B. D., Benedetti-Cecchi, L., Brainard, R. E., Brandt, A., Bulleri, F., Ellingsen, K. E., Kaiser, S., Kroncke, I., Linse, K., Maggi, E., O'Hara, T. D., Plaisance, L., Poore, G. C. B., Sarkar, S. K., Satpathy, K. K., Schuckel, U., Williams, A., Wilson, R. S.

Commonness and rarity in the marine biosphere

2014

James Cook University; Australian Institute of Marine Science; Smithsonian Institution; University of Western Australia; University of Calcutta; University of Pisa; NOAA Pacific Islands Fisheries Science Center; University of Hamburg; FRAM-High North Research Centre for Climate and the Environment; Senckenberg am Meer; British Antarctic Survey; Museum Victoria; Indira Gandhi Centre for Atomic Research; Commonwealth Scientific and Industrial Research Organization

Proceedings of the National Academy of Sciences

111

23

8524-8529

"Explaining patterns of commonness and rarity is fundamental for understanding and managing biodiversity. Consequently, a key test of biodiversity theory has been how well ecological models reproduce empirical distributions of species abundances. However, ecological models with very different assumptions can predict similar species abundance distributions, whereas models with similar assumptions may generate very different predictions. This complicates inferring processes driving community structure from model fits to data. Here, we use an approximation that captures common features of neutral? biodiversity models - which assume ecological equivalence of species - to test whether neutrality is consistent with patterns of commonness and rarity in the marine biosphere. We do this by analyzing 1,185 species abundance distributions from 14 marine ecosystems ranging from intertidal habitats to abyssal depths, and from the tropics to polar regions. Neutrality performs substantially worse than a classical nonneutral alternative: empirical data consistently show greater heterogeneity of species abundances than expected under neutrality. Poor performance of neutral theory is driven by its consistent inability to capture the dominance of the communities most-abundant species. Previous tests showing poor performance of a neutral model for a particular system often have been followed by controversy about whether an alternative formulation of neutral theory could explain the data after all. However, our approach focuses on common features of neutral models, revealing discrepancies with a broad range of empirical abundance distributions. These findings highlight the need for biodiversity theory in which ecological differences among species, such as niche differences and demographic trade-offs, play a central role."

metacommunities; marine macroecology; species coexistence; Poisson-lognormal distribution

10.1073/pnas.1406664111

This article contains supporting information online at www.pnas.org/lookup/suppl/doi:10.1073/pnas.1406664111/-/DCSupplemental