Key points are not available for this paper at this time.
Anne E Magurran (2004) Blackwell Science Ltd, Blackwell Publishing ISBN 0-632-05633-9 www.blackwellpublishing.com Soft cover, 260 pages, £32.50 African Journal of Aquatic Science 2004, 29(2): 285–286
J. H. O’Keeffe (2004) studied this question.