Foraminiferal Ecology and Paleoecology

Perhaps no fossil group is used as much as foraminifera for paleoecologic inference, both in academia and industry. Since the late 1960s, new concepts and much additional data have appeared that make it difficult for the casual worker not immediately concerned with foraminiferal ecology and paleoecology to stay abreast of the latest developments. In these notes, the authors summarize much of that information, or provide reference to more detailed sources. They also attempt to point out problems and other methods of dealing with them. Most paleoecologic work with foraminifera in the past has relied on direct comparison of fossil assemblages with the most similar modern assemblages, and inferring then that the environments were similar also. The method is used widely in scientific studies and in industrial applications. The result is based on the single hypothesis that the fossils are environmentally analogous to their modern counterparts. These notes present a number of alternative working hypotheses, and in some cases, examine the data to attempt of disprove them.
Ecology of Large, Shallow-Water, Tropical Foraminifera
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Published:January 01, 1979
Abstract
Among tropical foraminifers a number of families and genera reach large sizes, commonly ranging from 3 mm3 in volume to more than 300 mm3. Many of these are part of lineages that have extensive fossil records and formulation of an ecological framework for the extant representatives may have applicability to related foraminifers in carbonate deposits as old as Cretaceous and by analogy to the extinct late Paleozoic fusulinaceans. Most large, living foraminiferal genera are associated with a symbiotic photosynthetic partner. Some of these photosynthetic partners are zooxanthellae similar to those in tropical, shallow water, hermatypic corals. Most large foraminifers show one or more type of shell adaptation for the effective utilization of their symbionts. In general, large foraminifers are important constituents of coral reef ecological systems and are geographically limited in their distribution to surface water having temperatures greater than 200C, to shallow shelf areas in the upper part of the photic zone, and to normal (35.5 ppt or higher) salinities. Only a few larger genera, such as the alveolinids, are common in the middle part of the photic zone.