Alastair Grant
P.S.Z.N.: Marine Ecology 21 (2):97-112 (2000)
The communities of animals that live on the bed of the deep sea are, with only a few exceptions, very high in diversity. Much of the discussion of this high diversity has assumed that interspecific competition is strong and asymmetric and will rapidly lead to the elimination of many species by competitive dominants unless restrained by predation, disturbance or some other process. Early discussions of deep sea diversity made explicit comparisons with rocky shores where this model of competition holds true. Such comparisons are no longer made explicitly, but almost all of the recent discussions of the issue have implicitly assumed this model of community organisation.
However, a wealth of experimental studies on shallow water have repeatedly demonstrated that this model does not hold for sediment communities in shallow water. Here, competition is usually weak and the action of predators is to reduce diversity by eliminating many rare species rather than increasing diversity by restraining dominant competitors. Remarkably, these studies on shallow water sediments have gone almost completely unmentioned in recent reviews of deep sea diversity. The implications of this type of community organisation for the maintenance of diversity are discussed on the assumption that deep sea sedimentary communities are likely to function in a similar way.
For more detail, see the paper itself. Reprints are available from me on request: A.Grant@uea.ac.uk
Centre for Ecology, Evolution and
Conservation
School of Environmental
Sciences
University of East Anglia
Norwich
NR4 7TJ
UK
If you are interested in undergraduate study in ecology, environmental sciences or related fields, please look at the web pages describing the University of East Anglia's degree programmes in Ecology and Environmental Sciences.
If you would like a reprint of this paper, or are interested in opportunities for postgraduate research in this field, then please email A.Grant@uea.ac.uk.