Lab 6. Fossils of the Pre-Cambrian and Cambrian
Printer-friendly worksheets for Lab 6
Note: For this lab, questions are interspersed within the text of the lab rather than separated into Exercise sections. Use the worksheets to make sure you have answered all of the questions.
Time Interval
Goals
By the end of this lab you will:
- Understand taxonomy and the manner in which life on Earth is classified.
- Know how to use a systematic method to identify the major fossil groups.
- Have learned to identify some of the fossils from the Precambrian Eon and the Cambrian Period.
- Have explored the fauna of the Burgess Shale.
Introduction
Before reading this lab, read the Guide to Fossil Classification included in the lab manual introduction. This will provide you with an overview of Labs 6 to 8, and help explain exactly what information you are expected to remember.
In Lab 5, you examined how fossils are preserved in the rock record and gained some appreciation for the body materials that are the starting point for fossils. You also learned about some of the conditions in sedimentary environments that are more likely to preserve all or part of an organism as a fossil. In this lab, you will learn the biological classification scheme that is common to biology and paleontology and begin to examine the history of life on Earth.
A fossil classification flowchart is included in the Guide to Fossil Classification. Use this to make your own notes that will help you to remember how to identify the various fossils. You will be have access to a copy of the flow chart during the second lab exam. Lab 5 introduced some important features of fossils such a symmetry and shell coiling that are used in the flow chart to help determine which grouping a fossil belongs to.
In this lab, we will begin with fossils which emerged at the beginning of Earth’s history in the early Precambrian, and work forwards in time to the early Cambrian Period and the fossils of the Cambrian Explosion. This lab will introduce some of the major phyla (a high level grouping) that you will be expected to be able to recognize by the end of the course. Labs 7 and 8 will each step further forward in time, and each lab will introduce a few more phyla.
A Note About Fossil Illustrations
Many of the drawings in the next few labs will show examples of members of the phylum, order or class being discussed and are provided to highlight some of the major features of each. In some cases, fossil specimens that you will examine are the same as ones shown in the sketches, but in some cases they are not. You are not expected to identify these sketches, but they will be useful study guides. Many also include actual species names which you do not have to remember. Read over the Guide to Fossil Classification for guidance as to the level of detail you are expected to remember.