Our Brachiopod Brothers in Evolution

Abstract
As students we have been told again and again that fossils are the key to the mysteries of the past. They help us understand what has gone before on this sometimes chaotic and unpredictable Earth. We hope that by studying the fossil record, in our limited capacity, we can learn more about the various species of brachiopods that evolved in this area millions of years ago.
We have compared and contrasted brachiopod fossils of the formations in Liberty and Brookville, Indiana. We have also examined brachiopods, crinoids, bryazoa, and horn coral within the distinct layers of the Brookville site. The brachiopod fossils need to be identified by genus and (hopefully) species within different layers of a given formation, so we can identify them. We will then develop a key for the class by examining the length, the width, the ridges,
the hinges (whether they are articulated or inarticulated), the beak, the valves (shells), and general shape of the brachiopods.
Introduction
Our brachiopod fossils were just waiting for us on the side of the highway-- once we found the right highway, an entirely different challenge. These fossils will help us to answer the ever important question ñ are we alone in the universe? We hypothesize that the brachiopods will vary through the different layers. We tried to identify these brachiopods using a key in Fossil Ohio, but failed miserably. Our next step is to develop a key that we and the students can follow with the help of Joe Merak and Hays Cummins. All of these fossils are within the Ordovician Period. The different formations we are examining may include Drakes, Whitewater, Liberty, Waynesville, or Arnheim. Then we would like to examine the changes in the brachiopod fossils throughout the layers of the roadcut at Brookville.
Brachiopod identification seemed like a great project for many reasons. Of course, there is the pure fun of collecting our samples. There are many other very practical considerations: 1. This area is world famous for its unique and abundant amount of Ordovician fossils. 2. Fossils will not change during the course of our study. Famine, fire, war, locusts or even the dreaded early frost will not effect our results. We can do our research at our convenience. 3. Studying
brachiopods made sense, because they are both numerous and widespread throughout the local fossil formations. 4. We hope that students will better understand our planet and its past by examining these fossils. We hope to be able to examine different species of brachiopods through and within the different layers. We want to (correctly) identify different genuses of brachiopods. We are collecting a lot of fascinating fossils, and inspire others to become interested both in fossil collecting and the evolutionary process. Brightening Joe Marrickís boring day hidden in the corner of the infrequently visited Limper Geology Museum is also a goal.
Relevance Of Our Research
There has been little research into the evolution of brachiopods, even though our region provides fertile opportunities for discovering more about these fascinating creatures. We hope that by examining the relatively simple structures of brachiopods that we may gain a better understanding of evolution in general. (The necessity of taking a road trip to do research did not motivate us in any way whatsoever.)
We are building on the work done by Caster, Dalve and Pope. In the 1950ís they categorized the local Ordivician strata. Their work has served as a guide to fossil hunters and researchers who work in the Cincinnati area. We will identify these brachiopods by their
genuses, their variance in size, diversity of genuses, and by looking for trace fossils to identify the different strata.
The results of our experiment will clarify the unique history of the brachiopods of southwestern Ohio. Our hypothesis is a focused study in the larger search for knowledge in the area of evolution. By studying brachiopods in different layers, we can determine evolutionary differences and contributing factors to these differences of the brachiopods in the different strata.

Materials and Methods
Experimental Design: We have studied the rock formations in Brookville on Sunday, October 3rd and October 17th . The road cut exposes the Ordovician bedrock that served as our sample gathering place. We also collected samples from the roadside of Highway 1 outside Brookeville, Indiana. We took pictures of the strata formations and fossils. The pictures are being developed and put on the web to be used as a teaching aid for our discovery lab. After we brought the samples back from Indiana, we plan on spent the next week unsuccessfully trying to identify and categorize our fossils. First, we tried to organize them by genus using the books and guides provided to us by Hays and Mr. Merak, but we still could not identify them. So, we are going to take a field trip with our fossils to the Limper Geology Museum, on October 26th, to enlist the help of Mr. Merak on developing a key for identifying and organizing our finds. We are guessing that this may take a while depending on how many brachiopods we bring back. Some basic tools will be used in the examination process of our experiment. We will be using the Vernier Caliber to measure the fossils. A hammer and various dentistry tools will be used to excavate the fossils from the limestone. Furthermore, we will be using a magnifying glass to examine the fine details of the brachiopods. Jennyís camera and film will be used to document the locations we gathered fossils from. Finally the Internet will play an intregal part in helping us both display our work and link to the work of other fossil collectors and institutions.
We through working on our own and with Mr. Merak we will be able to develop a key to help identify the genus and species of brachiopods. By using this key and our photographs, we are going to ask the class to help us identify some of our brachiopod finds as our Discovery Lab. We will start the class with a brief overview of the Ordovician period using the Internet to aid us in the visual presentation. We will discuss the difficulties of working with the fossil record in general, and the challenges we specifically encountered. Then we will divide the class up into four groups with one of us leading each group. Each group will examine different layer or site from our fossil gathering expeditions. We will use the key we develop to aid this process, teaching the terminology for identifying the characteristics as we go. Then we will gather together and each group will make a brief presentation (once again using the Internet to present large pictures for everyone to examine) about a brachiopod species they have identified. This observation of how the brachiopods differ will help to give the class an understanding of the evolutionary process and an appreciation for the work of paleontologists.
We feel that our lab is sound because we have consulted with Hays and Mr. Merak (the curator at the geology museum) about the details of our experiment and research. Prior research and documentation has ensured that the brachiopods are indeed from different layers. We arenít doing any statistical analysis, since just identifying the fossils will encompass the entire class
period. We feel our design is adequate for our goals of inciting interest in the fossil record and evolution.
Our lab timeline was limited to the weekends, since we inevitably got lost for at least four hours on each excursion. First, a proposal for the project was devised on the thirtieth day of September in the year 1999. Secondly, we set out on October 6, 1999 to collect fossils from the formation near Liberty, Indiana on the Fairfield Causeway and from the formation near Brookville, Indiana on Highway 101. We returned to the outlying area of Brookville, Indiana on October 17, 1999 to collect fossils from the formation on Highway 1. On October 26th, we will visit Mr. Merak at the Limpier Geology Museum and develop our taxonomic key. Prior to class on November 9th, we will ask the class to visit our web site for a brief overview of the Ordovician period and our project in general.

Bibliography:
Feldmann, Rodney M.(1996) FOSSILS OF OHIO. Columbus: Ohio Department of Natural Resources.
Hansen, Michael. (1994, October). GEOFACTS (Files posted on the World Wide Web). Retrieved September 1, 1999 from the World Wide Web:
Ohio Geological Survey Home Page
Larsen, Glen. (1998, January). GEOFACTS (Files posted on the World Wide Web). Retrieved September 9, 1999 from the World Wide Web: Ohio Geological Survey Home Page
Sepkoski, J. & Miller, A.(1998). Analysing Diversification Through Time. TRENDS IN ECOLOGICAL & EVOLUTION, 13, 158-159.
Benton, M.J.(1998). Analyzing Diversification Through Time: Reply to Sepkoski and Miller.
TRENDS IN ECOLOGY & EVOLUTION, 13, 201.
Raff, R.A.(1999) Creating the Animal Planet. TRENDS IN ECOLOGY & EVOLUTION, 14, 39. Hadly, Elizabeth.(1999). Fidelity of Terrestrial Vertebrate Fossils to a Modern Eosystem. PALAEOGEOGRAPHY, PALAEOCLIMATOLOGY, PALAEOECOLOGY, 149, 389-409. Falls of the Ohio. ANCIENT SHELLS AT THE FALLS OF THE OHIO. (Files posted on the
World Wide Web). Retrieved September 9, 1999 form the World Wide Web: Falls of the Ohio Home Page.

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