Cenozoic cooling, Antarctic nutrient pump, and the evolution of whales

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doi: 10.1016/j.dsr2.2007.07.024
Author(s): Berger, W. H.
Author Affiliation(s): Primary:
Scripps Institution of Oceanography, La Jolla, CA, United States
Other:
Indiana University-Purdue University Indianapolis, United States
University of Salamanca, Spain
Volume Title: Paleoceanography and paleoclimatology of the Southern Ocean; a synthesis of three decades of scientific ocean drilling
Volume Author(s): Warnke, Detlef, editor; Filippelli, Gabriel M.; Flores, José-Abel
Source: Paleoceanography and paleoclimatology of the Southern Ocean; a synthesis of three decades of scientific ocean drilling, edited by Detlef Warnke, Gabriel M. Filippelli and José-Abel Flores. Deep-Sea Research. Part II: Topical Studies in Oceanography, 54(21-22), p.2399-2421. Publisher: Elsevier, Oxford, International. ISSN: 0967-0645
Note: In English. Based on Publisher-supplied data; illus.
Summary: The evolution of large marine mammals and their invasion of the pelagic realm is tied to the availability of sufficient food, which in turn is linked to upwelling areas and other highly productive regions in the ocean, as has been recognized for some time. Here I propose that silicate-supported upwelling (which provides the shorter food chain and hence the higher yield for apex consumers) and deep mixing within the Southern Ocean are the crucial ingredients of the system providing the stage for the evolution of whales. The Circumpolar Current receives silicate from various sources but especially from the North Atlantic Deep Water introduced in the Atlantic sector. The silicate is largely trapped in the Ring, some in the water, and some in the sediment, and is made available to shallower waters by unusually deep mixing. From these shallower depths silica-rich waters can enter the thermocline all through the southern hemisphere, stimulating diatom growth in upwelling systems to the equator and beyond. From the link diatoms-krill-whales and diatoms-krill-small fishes, it is readily apparent that the link between the climate narrative and the narrative of whale evolution (both for mysticetes and odontocetes) is the silica cycle. Studying it will generate hypotheses about whale evolution that can be tested using fossils. Abstract Copyright (2007) Elsevier, B.V.
Year of Publication: 2007
Research Program: DSDP Deep Sea Drilling Project
ODP Ocean Drilling Program
Key Words: 11 Paleontology, Vertebrate; Atlantic Ocean; Biologic evolution; Cape Basin; Carbon; Carbon cycle; Cetacea; Chordata; DSDP Site 216; Deep Sea Drilling Project; Drake Passage; Eutheria; Geochemical cycle; Indian Ocean; Leg 175; Leg 22; Mammalia; Marine environment; Ninetyeast Ridge; Nutrients; ODP Site 1084; Ocean Drilling Program; Ocean circulation; Paleo-oceanography; Paleoclimatology; Paleoecology; Paleoenvironment; Productivity; Silica; South Atlantic; Southern Ocean; Tetrapoda; Theria; Upwelling; Vertebrata
Coordinates: S253049 S253049 E0130140 E0130140
N012743 N012744 E0901229 E0901228
Record ID: 2010080333
Copyright Information: GeoRef, Copyright 2019 American Geosciences Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands