Lecture Biology (6e): Chapter 25 - Phylogeny and systematics. This chapter presents the following content: Sedimentary rocks are the richest source of fossils, paleontologists use a variety of methods to date fossils. | CHAPTER 25 Phylogeny and Systematics Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A1: The Fossil Record and Geological Time 1. Sedimentary rocks are the richest source of fossils 2. Paleontologists use a variety of methods to date fossils Evolutionary biology is about both processes (., natural selection and speciation) and history. A major goal of evolutionary biology is to reconstruct the history of life on earth. Systematics is the study of biological diversity in an evolutionary context. Part of the scope of systematics is the development of phylogeny, the evolutionary history of a species or group of related species. Introduction Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fossils are the preserved remnants or impressions left by organisms that lived in the past. In essence, they are the historical documents of biology. The fossil record is the ordered array in which fossils appear within sedimentary rocks. These rocks record the passing of geological time. Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Sedimentary rocks form from layers of sand and silt that settle to the bottom of seas and swamps. As deposits pile up, they compress older sediments below them into rock. The bodies of dead organisms settle along with the sediments, but only a tiny fraction are preserved as fossils. Rates of sedimentation vary depending on a variety of processes, leading to the formation of sedimentary rock in strata. 1. Sedimentary rocks are the richest source of fossils Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings The organic material in a dead organism usually decays rapidly, but hard parts that are rich in minerals (such as bones, teeth, shells) may remain as fossils. Under the right conditions minerals dissolved in groundwater seep into the tissues of dead organisms, replace its organic material, and create a cast in the shape of the organism. . | CHAPTER 25 Phylogeny and Systematics Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Section A1: The Fossil Record and Geological Time 1. Sedimentary rocks are the richest source of fossils 2. Paleontologists use a variety of methods to date fossils Evolutionary biology is about both processes (., natural selection and speciation) and history. A major goal of evolutionary biology is to reconstruct the history of life on earth. Systematics is the study of biological diversity in an evolutionary context. Part of the scope of systematics is the development of phylogeny, the evolutionary history of a species or group of related species. Introduction Copyright © 2002 Pearson Education, Inc., publishing as Benjamin Cummings Fossils are the preserved remnants or impressions left by organisms that lived in the past. In essence, they are the historical documents of biology. The fossil record is the ordered array in which fossils appear within sedimentary rocks. .
