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Transfers of algal, microfossil, plant, and vertebrate materials to the University of California Museum of Paleontology
- Jere H. Lipps, Karen L. Wetmore
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- Journal:
- Journal of Paleontology / Volume 67 / Issue 5 / September 1993
- Published online by Cambridge University Press:
- 20 May 2016, pp. 894-898
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The university of California Museum of Paleontology (UCMP), located on the Berkeley Campus, is a major repository of fossils and paleontological materials. The collection, one of the largest in the nation, originated in 1873 and has been added to continuously since then. In 1921, the Museum of Paleontology was officially initiated with an endowment though the generosity of Annie Alexander of Oakland, California (Grinnell, 1958). The UCMP collections are divided into four specimen collection management units and one collection of paleontological materials, such as rock, sediment, and amber samples, and various teaching collections. The specimen collection units are Fossil Prokaryotes and Protists, Fossil and Recent Invertebrates, Paleobotany and Palynology, and Vertebrate Paleontology. Each of these units has its own manager and each consists of hundreds of thousands of specimens or more and thousands of primary and secondary type specimens. The Museum is supported by the Annie Alexander Endowment and the University of California, Berkeley. It has a staff of 11, and a group of faculty curators, affiliate faculty curators from other University of California campuses, research associates, and associated graduate and undergraduate students. It is a general purpose research museum open to the scientific community and, although it does no formal instruction, it provides instructional exhibits and teaching collections at Berkeley and other campuses. It publishes Paleobios (ISSN 0031-0298), an occasional publication containing a variety of paleontological, peer-reviewed papers. UCMP is also involved in public and school activities at the Museum in Berkeley and at the University of California, Berkeley, Museum of Science, Art and Culture, at Blackhawk Plaza, Danville, California.
Macroevolutionary differences between the two major clades of Neogene planktonic foraminifera
- Steven M. Stanley, Karen L. Wetmore, James P. Kennett
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- Journal:
- Paleobiology / Volume 14 / Issue 3 / Summer 1988
- Published online by Cambridge University Press:
- 08 February 2016, pp. 235-249
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Being of especially high quality, the Neogene fossil record of planktonic foraminifera offers special opportunities for assessing patterns of extinction and speciation. A variety of metrics indicates that within this group the mean duration of lineages has been much shorter (rate of extinction has been higher) for the globorotaliid clade than for the globigerinid clade. Furthermore, in the globorotaliid clade rates of extinction and speciation have not been closely linked to changes in diversity, but rather have been relatively high even at times when diversity has undergone little change. Thus, the globorotaliid clade has undergone more rapid evolutionary turnover than the globigerinid clade. Data for living species reveal that neither geographic range nor temperature tolerance is the primary factor controlling lineage duration. On the other hand, there is evidence that lineages marked by low abundance (small population size) are relatively short-lived. The reason that globorotaliid lineages have generally survived for shorter intervals, on the average, may be that their populations have been less abundant and less stable. Usually they live deeper in the water column, where food is often sparse, and many flourish only in areas of upwelling. Furthermore, the globorotaliids lack symbiotic algae for nutritional support. The same ecological factors may have accelerated speciation in the globorotaliid clade, by causing species to be patchily distributed. Thus, population size and structure have been more important than geographic range in determining rates of extinction and speciation. This parallels the situation for Neogene marine bivalves.
For planktonic foraminifera, as for Western Atlantic Bivalvia, the normal pattern of extinction was reversed in late Pliocene time, apparently in response to climatic cooling. The globigerinids suffered a sudden pulse of extinction. The deeper dwelling globorotaliids fared better; probably many of their species benefited from elevation of the seasonal thermocline into the photic zone. At the same time, rate of speciation declined in the globorotaliid clade, which supports the idea, inferred from the evolutionary history of marine bivalves, that an increase in the size and stability of populations should depress both rate of extinction and rate of speciation.