FORAMINIFERA IN THE
MIDDLE SCHOOL CLASSROOM

INTRODUCTION

The diversity of foraminifera in the geologic record (more than 40,000 species) and in the modern marine realm (more than 6,000 species) provides abundant data which can be applied to a broad spectrum of scientific problems throughout earth's history. Their microscopic size (.1 mm - 1 cm) and wide geographic distribution in both modern and ancient seas result in the availability of billions of their shells through drilling, dredging or plankton towing. Because the ocean habitats of modern foraminifera have been well-documented, this group of protists serves as a monitor for marine environments and a proxy for paleoenvironments throughout the history of the oceans. Some scientific investigations employing foraminifera as a primary tool include:
1) study of climate through geologic time and related ocean history by examining "cool-," "temperate-," and "warm-water" species preserved in the rock record;
2) use of modern foraminifera as environmental indicators in coastal bays and estuaries;
3) application of the fossil record of foraminifera to the study of evolutionary concepts and theories and concomitant development of a geologic time scale; and
4) interpretation of past environments, particularly water-depth, using the distribution of modern benthic foraminifera as a key to the fossil record.

Applications to the classroom — The study of foraminifera in the middle school classroom encompasses many of the topics covered in both the life and earth sciences curricula. Middle school science students often learn important scientific principles in a compartmentalized fashion. The next level of learning should foster students breaking the walls of these "compartments" and promote an integrated flow of many concepts to address a scientific problem. A thematic discussion of various topics, all centered around foraminifera, gives the student a sense of the cohesiveness of many disciplines of science. Because foraminifera are single-celled organisms representative of Protista, a direct analogy can be made with the introduction in life science class of the cell and its various processes and parts. Live cultures of Amoeba proteus are an excellent link with the study of foraminifera because there are both similarities and differences between these two types of organisms which permit a "compare and contrast" exercise.
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The size of foraminifera lends itself well to the introductory study of the microscope. Most studies of foraminifera are completed using a reflective light, binocular microscope. Ready sources of foraminifera samples are available both commercially and free. For example, samples of tropical beach sand from many of the islands in the Caribbean are available from scientific supply catalogues (Ward's, Curtin, etc.). These samples contain abundant foraminifera. Alternative sources include micropaleontologists at a petroleum corporation, the US Geological Survey of the Department of the Interior, at a local university. Many of these people have extra samples they might donate for classroom study. In addition, you can obtain modern samples from rock samples which can be processed. (See Snyder and Huber, this web site for preparation techniques.)

The scanning electron microscope (S.E.M.) is used to study particular species of foraminifera. This lends itself well to discussions of the electron microscope and how it compares and contrasts with both the reflective light, binocular microscope and the compound microscope. A great enhancement to this segment is to take students on a field trip to see a scanning electron microscope. My students were invited to Mobil Oil Corporation to see the various applications of the S.E.M. in the quest for petroleum. We observed foraminifera, small rock fragments and even a lice specimen. I have no doubt that these students now have a 3-D visual image to associate with the S.E.M. My experience is that teachers are often hesitant to "bother" professionals about an event for their class unless the scientist is the parent of a student. Having worked on the industry side of the fence, I can tell you that it is an event most scientists enjoy. Not only does the scientist get to talk about a favorite subject to a captured audience, a break from the often "routine" nature of the scientific process is a welcomed change.

Investigations of past climate using foraminifera constitute an application of "cause and effect" scenarios in science. A particular species of foraminifera, Neogloboquadrina pachyderma, is known to coil its test (shell) in different directions based on the temperature of the ambient watermass. In general, when surface water temperatures are less than 8°C, left-coiling forms dominate the Neogloboquadrina pachyderma population. When temperatures are higher than 8°C, right-coiling forms of the species dominate the population. If this scenario is applied to the recent geologic past, great insight can be obtained into paleoclimatic variations. Climatic oscillations accompanied by changes in ice volume on Earth are a potential cause. The subsequent effect observed in the fossil record would be the ratios of the different coiling directions of Neogloboquadrina pachyderma. In addition, a link with math is possible by calculating percentage data and actually plotting the data to make interpretations. An application of this technique for middle school students follows this article.

Reconstruction of environments at different times during the geologic past is also derived from the study of micropaleontology, particularly benthic foraminifera. Modern benthic foraminifera are distributed according to parameters of their preferred habitat. Often these parameters are correlated with ocean depth. Therefore, foraminifera are employed to infer paleoenvironments in the geologic record. If a particular foraminifera today flourishes at 50- 150m of water depth in the modern ocean, a Pliocene(2.5 Ma) foraminiferal species of similar morphology (perhaps pertaining to the same genus) is inferred to indicate similar paleo-water depths. Drastic changes in water-depths through time at a particular locality are indicative of many geologic factors. For example, a shallowing of water depths through time may be a result of tectonic forces uplifting the earth near an ocean margin. Students are asked to interpret the paleo-water depth of a particular region at a geologic time slice in an activity following this article.
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Integrating foraminifera into the middle school science curriculum addresses a variety of interesting problems. Each activity can be incorporated separately when a particular topic is covered (i.e., the cell) in the science classroom. Alternatively, the activities can be completed over a week in a thematic session on foraminifera. Most students are entranced by the grandeur of dinosaurs in the fossil record. The students I have seen exposed to foraminifera are equally impressed by the complexity and beauty of life on such a small scale. Hopefully, through the use of these activities, your students will understand that a problem is not necessarily biological or geological or environmental in nature; rather, a well-trained scientist uses all the tools available to address a scientific problem.

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