BSCI393 Term Project:
During the course of the semester you will be required to reconstruct the population attributes of a benthic invertebrate species of your own choosing. You should work in your established lab groups. You will need to have the project completed by the last full week of classes, when oral presentations and written summaries are due.
We will be taking a field trip to Calvert Cliffs to examine the bivalve faunas of the Drum Cliff and Boston Cliffs Members of the Choptank Formation on October 13. This is an excellent site to collect your specimens for study.
- Select an organism that you find intrinsically interesting. The table shown below lists a number of possible genera that are suitable for study.
- The species should be reasonably abundant. You should attempt to collect at least 100 specimens for your study. Rare species will probably be too uncommon to collect in sufficient quantity during the semester. Also, since 100+ specimens will occupy a comparatively large and very heavy mass of sediment, the specimens should be removed from the matrix in the field. Consequently, you will be transporting a MUCH smaller weight of material back to the laboratory.
- You will need specimens that are more-or-less complete in order to obtain measurements of body size. A thousand fragments will be worthless for this study. However, there is a means of circumventing the problem of broken specimens. If a particular body part, such as the cephalon of trilobites, is frequently preserved intact, measurements on that part can be used as a body size metric for your study.
- Make certain not to bias your sample toward larger-sized individuals. Walking along and picking up obvious specimens will tend to produce a sample with an under-representation of smaller individuals. Get down and your hands and knees and collect every specimen you can find.
- Collect your specimens from a single horizon. Collecting the same species from two or more horizons will only add confusion to your data, because you will be mixing together different populations from different environmental settings. At Matoaka Cottages, the Drum Cliff member is a blue-gray clay, whereas the Boston Cliffs Member is reddish. This fact should enable you to determine the source of fosils that have eroded out of the cliffs.
Most of the specimens you collect at Matoaka Cottages will be "float" - i.e. no longer embedded in sediment. Therefore, collecting should not require special excavation equipment. Indeed, you should not excavate anything from the cliff without the instructor's permission and supervision. Nevertheless, you are welcome to bring equipment such as chisels, awls, and brushes if you have them. You should carry:
- several large zip lock bags
- toilet paper in which to wrap fragile specimens
Storage space will be provided in the laboratory for your specimens during the semester. At the end of the semester, along with your final report, we request that you provide two or three representative specimens of your research species to become part of the reference material for the course.
Recommended fossil bivalves for use in term projects.