White Rose University Consortium logo
University of Leeds logo University of Sheffield logo York University logo

Niches, rather than neutrality, structure a grassland pioneer guild

Turnbull, L.A., Manley, L. and Rees, M. (2005) Niches, rather than neutrality, structure a grassland pioneer guild. Proceedings of the Royal Society B: Biological Sciences, 272 (1570). pp. 1357-1364. ISSN 1471-2954


Download (259Kb)


Pioneer species are fast-growing, short-lived gap exploiters. They are prime candidates for neutral dynamics because they contain ecologically similar species whose low adult density is likely to cause widespread recruitment limitation, which slows competitive dynamics. However, many pioneer guilds appear to be differentiated according to seed size. In this paper, we compare predictions from a neutral model of community structure with three niche-based models in which trade-offs involving seed size form the basis of niche differentiation. We test these predictions using sowing experiments with a guild of seven pioneer species from chalk grassland. We find strong evidence for niche structure based on seed size: specifically large-seeded species produce fewer seeds but have a greater chance of establishing on a per-seed basis. Their advantage in establishment arises because there are more microsites suitable for their germination and early establishment and not directly through competition with other seedlings. In fact, seedling densities of all species were equally suppressed by the addition of competitors' seeds. By the adult stage, despite using very high sowing densities, there were no detectable effects of interspecific competition on any species. The lack of interspecific effects indicates that niche differentiation, rather than neutrality, prevails.

Item Type: Article
Copyright, Publisher and Additional Information: Copyright © 2005 The Royal Society. Reproduced in accordance with the publisher's self-archiving policy.
Keywords: competition/colonization trade-off, seed size, niche partitioning, seed limitation, neutral models, coexistence mechanisms
Institution: The University of Sheffield
Academic Units: The University of Sheffield > Faculty of Science (Sheffield) > School of Biological Sciences (Sheffield) > Department of Animal and Plant Sciences (Sheffield)
Depositing User: Repository Officer
Date Deposited: 26 Jun 2006
Last Modified: 11 Jun 2014 08:40
Published Version: http://www.journals.royalsoc.ac.uk/openurl.asp?gen...
Status: Published
Publisher: The Royal Society
Refereed: Yes
Identification Number: 10.1098/rspb.2005.3084
URI: http://eprints.whiterose.ac.uk/id/eprint/1397

Actions (repository staff only: login required)