The History of Life on Earth CHAPTER NEW CHAPTER The History of Life on Earth the BIG idea 1.1 1.2 1.3 Living things, like Earth itself, change over time. Earth has been home to living things for about 3.8 billion years. Species change over time. Many types of evidence support evolution. CHAPTER OUTLINE

Earth has been home to living things for about 3.8 billion years. 1.1 Earth has been home to living things for about 3.8 billion years. Fossil records inform humans about the development of life on Earth. Information from fossils can help scientists reconstruct Earth's history. fossil unicellular organism multicellular organism mass extinction 250 million years ago 70 million years ago 55 million years ago SECTION OUTLINE

Species change over time. 1.2 Species change over time. Darwin's theory of natural selection explains evolution. evolution Four principals of natural selection are natural selection • overproduction Overproduction adult salmon eggs adaptation speciation SECTION OUTLINE

Species change over time. 1.2 Species change over time. Darwin's theory of natural selection explains evolution. evolution Four principals of natural selection are natural selection • overproduction adaptation • variation Variation curve speciation SECTION OUTLINE

Species change over time. 1.2 Species change over time. Darwin's theory of natural selection explains evolution. evolution Four principals of natural selection are natural selection • overproduction adaptation Adaptation • variation speciation • adaptation SECTION OUTLINE

Species change over time. 1.2 Species change over time. Darwin's theory of natural selection explains evolution. evolution Four principals of natural selection are natural selection • overproduction adaptation Selection • variation speciation • adaptation • selection SECTION OUTLINE

Many types of evidence support evolution. 1.3 Many types of evidence support evolution. Three different types of evidence provide a bigger picture of evolution ancestor vestigial organ fossil genetic gene biological SECTION OUTLINE

1.1 Earth has been home to living things for about 3.8 billion years. I. Earth has been home to living things for about 3.8 billion years. fossil A. Fossils provide evidence of earlier life. unicellular organism 1. Types of Fossils multicellular organism 2. Finding the Age of Fossils 3. Assembling the Fossil Record mass extinction B. More complex organisms developed over time. 1. Unicellular Organisms 2. Multicellular Organisms 3. Life on Land C. Earth’s history includes mass extinctions. 1. Permian Extinction 2. Cretaceous Extinction KEY CONCEPT SUMMARY

1.2 Species change over time. II. Species change over time. evolution A. Scientists explore the concept of evolution. natural selection 1. Early Ideas adaptation 2. Darwin’s Observations speciation B. Natural selection explains how living things evolve. 1. Overproduction 2. Variation 3. Adaptation 4. Selection 5. Isolation KEY CONCEPT SUMMARY

1.2 Species change over time. II. Species change over time. evolution C. New species develop from earlier species. natural selection 1. Speciation adaptation 2. Isolation speciation KEY CONCEPT SUMMARY

1.3 Many types of evidence support evolution. III. Many types of evidence support evolution. ancestor A. Observations provide evidence for theories. vestigial organ B. Fossil evidence supports evolution. gene C. Biological evidence supports evolution. 1. Similarities in Structure 2. Similarities in Development D. Genetic evidence supports evolution. KEY CONCEPT SUMMARY