ChapTitleBig10 The Origin and Diversification of Life on EarthChapTitleSmallUNDERSTANDING BIODIVERSITY

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Life on earth most likely originated from non-living materials.

  • 10.1 Complex organic molecules arise in non-living environments.
  • 10.2 Cells and self-replicating systems evolved together to create the first life.
  • 10.3 This is how we do it: Could life have originated in ice, rather than in a “warm little pond”?

Species are the basic units of biodiversity.

  • 10.4 What is a species?
  • 10.5 How do we name species?
  • 10.6 Species are not always easily defined.
  • 10.7 How do new species arise?

Evolutionary trees help us conceptualize and categorize biodiversity.

  • 10.8 The history of life can be imagined as a tree.
  • 10.9 Evolutionary trees show ancestor-descendant relationships.
  • 10.10 Similar structures don’t always reveal common ancestry.

Macroevolution gives rise to great diversity.

  • 10.11 Macroevolution is evolution above the species level.
  • 10.12 The pace of evolution is not constant.
  • 10.13 Adaptive radiations are times of extreme diversification.
  • 10.14 There have been several mass extinctions on earth.

An overview of the diversity of life on earth: organisms are divided into three domains.

  • 10.15 All living organisms are classified into one of three groups.
  • 10.16 The bacteria domain has tremendous biological diversity.
  • 10.17 The archaea domain includes many species living in extreme environments.
  • 10.18 The eukarya domain consists of four kingdoms: plants, animals, fungi, and protists.

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