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OverviewWhatever theory may be advanced to explain diurnal migration, the underlying reactions involved must be demonstrated conc- sively in the laboratory before the explanation can be ?nally accepted George L. Clarke 1933 p. 434 In oceans and lakes, zooplankton often make diel vertical migrations (DVM), descending at dawn and coming up again in late afternoon and evening. The small animals cover distances of 10–40 m in lakes or even a few hundred metres in the open oceans. Although not as spectacular as migrations of birds or the massive movements of large mammals over the African savannas, the numbers involved are very large and the biomass exceed the bulk of the African herds. For example, in the Antarctic oceans swarms of “Krill” may cover kilometres across, with thousands of individuals per cubic metre. These Euphausiids are food for whales, the most bulky animals on earth. Zooplankton are key species in the pelagic food web, intermediary between algae and ?sh, and thus essential for the functioning of the pelagic community. Prey for many, they have evolved diverse strategies of survival and DVM is the most imp- tant one. Most ?sh are visually hunting predators and need a high light intensity to detect the often transparent animals. By moving down, the well-lit surface layers are avoided but they have to come up again at night to feed on algae. Full Product DetailsAuthor: Joop RingelbergPublisher: Springer Imprint: Springer Edition: 2010 ed. Dimensions: Width: 15.50cm , Height: 4.10cm , Length: 23.50cm Weight: 0.791kg ISBN: 9789048130924ISBN 10: 9048130921 Pages: 356 Publication Date: 26 November 2009 Audience: Professional and scholarly , Professional & Vocational Format: Hardback Publisher's Status: Active Availability: Awaiting stock The supplier is currently out of stock of this item. It will be ordered for you and placed on backorder. Once it does come back in stock, we will ship it out for you. Table of ContentsReviewsAuthor InformationTab Content 6Author Website:Countries AvailableAll regions |