Book contents
- Understanding the Tree of Life
- Series page
- Understanding the Tree of Life
- Copyright page
- Reviews
- Epigraph
- Contents
- Foreword
- Preface
- Acknowledgments
- 1 Introduction to the Tree of Life: Drawing Trees and Why There Is No Trunk
- 2 Human Origins: We Are African … Mostly
- 3 Primates: Our Closest Living Cousins
- 4 Which Mammals Are the Most Primitive? None of Us
- 5 Birds Are Reptiles, Birds Are Theropod Dinosaurs
- 6 The Crawl Onto Land: Tetrapod Evolution and the Gain and Loss of Limbs
- 7 Which Fishes Are “Primitive”? Do Fish Even Exist?
- 8 Animal Evolution: Sponges and Comb Jellies Are Our Cousins
- 9 Plants, Animals, Fungi, and “Protists”: We Are Eukaryotes
- 10 Archaea Then Bacteria Are Our Most Distant Cousins
- Concluding Remarks: The Success, Importance, and Conservation of All Life
- Summary of Common Misunderstandings
- References and Further Reading
- Figure Credits
- Index
1 - Introduction to the Tree of Life: Drawing Trees and Why There Is No Trunk
Published online by Cambridge University Press: aN Invalid Date NaN
Book contents
- Understanding the Tree of Life
- Series page
- Understanding the Tree of Life
- Copyright page
- Reviews
- Epigraph
- Contents
- Foreword
- Preface
- Acknowledgments
- 1 Introduction to the Tree of Life: Drawing Trees and Why There Is No Trunk
- 2 Human Origins: We Are African … Mostly
- 3 Primates: Our Closest Living Cousins
- 4 Which Mammals Are the Most Primitive? None of Us
- 5 Birds Are Reptiles, Birds Are Theropod Dinosaurs
- 6 The Crawl Onto Land: Tetrapod Evolution and the Gain and Loss of Limbs
- 7 Which Fishes Are “Primitive”? Do Fish Even Exist?
- 8 Animal Evolution: Sponges and Comb Jellies Are Our Cousins
- 9 Plants, Animals, Fungi, and “Protists”: We Are Eukaryotes
- 10 Archaea Then Bacteria Are Our Most Distant Cousins
- Concluding Remarks: The Success, Importance, and Conservation of All Life
- Summary of Common Misunderstandings
- References and Further Reading
- Figure Credits
- Index
Summary
All species on Earth share common ancestry – we are all part of the same family tree. The tree of life is a representation of how all those species are related to one another. All living species on Earth are the product of billions of years of evolution, so all are evolutionary equals in that way. However, we tend to think of life in a hierarchical way. We think there are lower animals and higher animals. We may incorrectly think that species of bacteria are old and primitive, and that humans are recent and advanced. Many news articles about evolution can feed into the perceptions that some species are younger, more advanced, or more evolved. But all of those perceptions are misleading. Each of these present-day species are our evolutionary cousins. All species alive today are the product of the same 3.5 billion years of evolutionary change, each adapting to their own environment. (Note that species are the units of evolution, frequently defined based on the distinctiveness of their appearance and genetics, and often on their ability to interbreed and produce fertile offspring.)
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- Understanding the Tree of Life , pp. 1 - 21Publisher: Cambridge University PressPrint publication year: 2025
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