The Biology of the Deep Ocean

The deep sea environment is the most extensive on our planet. Its denizensare normally unseen but whenever they are exposed to view they are regarded asbizarre aliens from a different world. The Biology of the Deep Ocean takes aclose look at this apparently hostile world and explains how its inhabitants areexquisitely adapted to survive and flourish within it.The book begins with an analysis of how conditions in the oceanic environmentdiffer from those in the familiar terrestrial world and then describes thetechniques (and ingenuity) required to reveal the populations inhabiting thecolossal volume of the deep oceans. A section on primary production emphasizeshow almost all deep-sea life depends ultimately on the phytoplankton at thesurface and the export flux to deeper water. The ultimate beneficiaries of thisexport, the populations on the deep-sea floor, are then discussed, together withthe unique fetures of life fuelled by chemosynthesis at hydrothermal vents andcold seepts. The horizontal and vertical distribution patterns of deep-seaanimals, and their changes in time and space, are controlled by physical,biological and historical factors. The rapid reduction of biomass with depthputs a high priority on effiecinet prey capture and energy conservation.Chapters on energy efficiency, mechanoreception, chemoreception and visionreveal the extraordinary adaptations necesary for success. Accounts of theeffector systems involved in colour, camouflage and bioluminescence heighten theconcept of a different world. A chapter on animal life styles emphasizes thelinks between size, sex, and seasonality, visible in the contrasting benefits ofgigantism, dwarf males and the ability to respond to a periodic influx of foodfrom the surface. The final chapter and appendix deal with the unique andexciting variety of life in the deep ocean, formalized as biodiversity. Itsdifferent expression on the sea floor and in midwater invites both comparisonswith rain forest and concerns about its fraility, taking the reader back to theemphasis in the first chapter on how little we still know about this criticalhabitat.