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
Concluding Remarks: The Success, Importance, and Conservation of All Life
Published online by Cambridge University Press: 19 September 2025
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
Evolution has produced roughly 2.5 million described extant species, and likely at least 5–10 million more undescribed species. The tree of life conceptually unites all the species and lineages of life on Earth as explored in this book. Our species is just the tip of one tiny branch on the vast tree of life (Figure C.1). We do not stand out “above” other lineages; we are not “evolutionarily superior” to other organisms. Each leaf at the tips of the branches of the tree of life represents evolutionary success. Each extant species on the tree of life has evolved to be well suited to its environment, to its own ecological niche. Furthermore, all life is dependent on other life. That is because we have all coevolved with one another. We are dependent on our cousins, and given our ability to impact so much of the environment, they are dependent on us.
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- Understanding the Tree of Life , pp. 186 - 188Publisher: Cambridge University PressPrint publication year: 2025
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