Evol Ecol Res 2: 353-363 (2000)     Full PDF if your library subscribes.

Interspecific variation in seed mass and the co-existence of conifer species: A null model test

Joseph A. Veech,1 David A. Charlet2 and Stephen H. Jenkins1

1Department of Biology, University of Nevada, Reno, NV 89557-0015 and 2Department of Science – S2B, Community College of Southern Nevada, North Las Vegas, NV 89030, USA

Author to whom all correspondence should be addressed:
e-mail: javeech@scs.unr.edu


In many plant communities, there is remarkable variation in seed mass among co-existing species. Plant ecologists have focused on explaining the evolution of this variation but have directed relatively little attention towards examining its significance for species co-existence. This study represents the first empirical attempt to link variation in seed mass with species co-existence. Recent models have suggested that variation in seed mass may promote species co-existence if seedlings compete and if a trade-off exists between seed number and seed mass. We used a null model to test whether the pattern of interspecific variation in seed mass in 124 assemblages of montane conifer species was random or non-random. In most assemblages (mountain ranges), the variation appeared to be random. However, in assemblages consisting solely of pine species, seed masses were more evenly spaced than expected by chance alone. We therefore conclude that variation in seed mass is not important to species co-existence in diverse conifer assemblages but it may promote co-existence among pine species. Further empirical tests are needed before ecologists can come to a consensus opinion concerning the role of variation in seed mass in species co-existence.

Keywords: conifer, Great Basin, null model, seed size variation.

IF you are connected using the IP of a subscribing institution (library, laboratory, etc.)
or through its VPN.


        © 2000 Joseph A. Veech. All EER articles are copyrighted by their authors. All authors endorse, permit and license Evolutionary Ecology Ltd. to grant its subscribing institutions/libraries the copying privileges specified below without additional consideration or payment to them or to Evolutionary Ecology, Ltd. These endorsements, in writing, are on file in the office of Evolutionary Ecology, Ltd. Consult authors for permission to use any portion of their work in derivative works, compilations or to distribute their work in any commercial manner.

       Subscribing institutions/libraries may grant individuals the privilege of making a single copy of an EER article for non-commercial educational or non-commercial research purposes. Subscribing institutions/libraries may also use articles for non-commercial educational purposes by making any number of copies for course packs or course reserve collections. Subscribing institutions/libraries may also loan single copies of articles to non-commercial libraries for educational purposes.

       All copies of abstracts and articles must preserve their copyright notice without modification.