by Jere H. Lipps, President, Cushman Foundation for Foraminiferal Research, Inc.
[email protected]
Microfossils have perhaps one of the best fossil records of any group of organisms. These tiny fossils include whole skeletons or parts thereof so small that they cannot be seen by the naked eye and thus a microscope of some kind is required to see them. They include representatives from most phylogenetic groups—animals, plants, protists, algae, and various microbes (Fig. 1). Many of them are particularly useful in biostratigraphic, environmental, and paleoceanographic interpretations going back about ½ billion years. Bacteria and algal eukaryotes go back even farther, some to the origin of life itself at nearly 4 billion years. Single-celled protists with skeletons, like foraminifera, radiolaria, diatoms, coccoliths, tintinnids, silicoflagellates, and others, are abundant in both marine and nonmarine Phanerozoic rocks.
Microfossils are not commonly collected by avocational paleontologists, although in the past, people with microscopes, like doctors or their spouses, collected diatoms (micro-algae with siliceous skeletons) and arranged them on glass slides into pictures formed by their unique shapes and patterns. These were traded among the advocates. Foraminifera (forams) were rarely collected by amateurs, even though they are easily retrieved from marine rocks exposed in most places in the world and have been around since the latest Precambrian. Forams also are perhaps the best known microfossils because they have been intensely studied scientifically in geology since the late 1800s for biostratigraphic and paleoenvironmental interpretations, particularly in the oil industry, and more recently in modern ecology and biology, including phylogenetics.
Forams (Fig. 2) are diverse and super-abundant compared to larger fossils, so much so that statistically-valid samples are easy to collect and prepare from small hand or core samples. They have occupied every marine habitat from the very deepest oceans to the shallowest pelagic and near-shore. They have been critical in biostratigraphy of marine strata as old as the Ordovician, and they also provide environmental inferences of wide interest, having been used to detect ancient climate change, earthquakes, tsunamis, pollution, invasions of exotic species, function, extinctions, and ocean chemistry and productivity. They have been common rock-forming organisms as exemplified by fusulinid (foram) limestones, nummulitic (foram) rocks forming the pyramids of Egypt (Fig. 3), the oozes found in the deep sea, some beach sand (star sands), and many others. Although most are smaller than a pin head, some forams are quite large, especially for single-celled organisms, ranging up to about 10 cm long. Even though they are single cells, forams have a well-documented evolutionary history that rivals any known from animals or plants, and that record matches the evolutionary events inferred for these larger organisms.
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For many years, the oil industry employed thousands of foram workers worldwide to assist in the discovery and recovery of petroleum at depth in the earth’s crust. One of the first workers to demonstrate their usefulness in finding oil was Joseph Augustine Cushman (Fig. 4), who began working with forams in 1910 and soon started with an oil company in Mexico where he demonstrated the usefulness of forams in oil exploration. He then established a laboratory of foram research in Sharon, Massachusetts, and in the next 40 years published over 700 papers on forams in a variety of journals, including his own Contributions from the Cushman Laboratory for Foraminiferal Research. He described hundreds of new genera and species, their occurrences in modern sediments, their biostratigraphy, and their classification. He established foram micropaleontology in America after it had prospered for 100 years previously in France, England, and Germany. J. A. Cushman died in 1949 bequeathing a huge collection of forams (0.5 million; 150,00 slides) from all ages and around the entire globe as well as 4000 library items among others to the Smithsonian Institution. He was deeply admired by foram workers who then wished to continue foram work, based chiefly at the Smithsonian’s Natural History Museum in Washington, DC, where his collection of forams and library were deposited. His material is now curated in the Cushman Room at the Museum. See http://paleobiology.si.edu/cushman/legacy.html for more information about Cushman and his life.
Thus, in 1950, members of the staff of the USNHM, particularly Al Loeblich, Jr. and his wife, Helen Tappan (Fig. 5), and Ruth Todd, among others, established the Joseph A. Cushman Foundation for Foraminiferal Research, Inc. based at the Smithsonian. It initially published the Contributions from the Cushman Foundation for Foraminiferal Research, closely reminiscent of Cushman’s own publication series. After 20 years, the Contributions were renamed and reformatted as the Journal of Foraminiferal Research, now in its 46th annual volume. The Foundation itself has existed now for 66 years under the guidance of a 15-person Board of Directors. It provides student research and travel support, awards to advanced scholars, and the Joseph A. Cushman Award for Excellence in Foraminiferal Research, as well as other services for foram and paleo workers including an informative website (http://www.cushmanfoundation.org/) on foraminifera. Membership is open to anyone interested in forams and we welcome the amateur community.
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