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The Diversity of Life I. An Overview
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The Diversity of Life I. An Overview A. Classifying Organisms
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The Diversity of Life I. An Overview A. Classifying Organisms Initially, using a Platonic, typological concept, Linnaeus and others created a nested, hierarchical system.
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The Diversity of Life I. An Overview A. Classifying Organisms Initially, using a Platonic, typological concept, Linnaeus and others created a nested, hierarchical system. Evolution explained this nested pattern as a consequence of descent from common ancestors.
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The Diversity of Life I. An Overview A. Classifying Organisms Initially, using a Platonic, typological concept, Linnaeus and others created a nested, hierarchical system. Evolution explained this nested pattern as a consequence of descent from common ancestors. Modern biologists view the classification system as a means of showing the phylogenetic relationships among groups.
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The Diversity of Life I. An Overview A. Classifying Organisms Initially, using a Platonic, typological concept, Linnaeus and others created a nested, hierarchical system. Evolution explained this nested pattern as a consequence of descent from common ancestors. Modern biologists view the classification system as a means of showing the phylogenetic relationships among groups. Genetic relatedness should be the basic for biological classification... Genus Felis Genus Panthera Family Felidae
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The Diversity of Life I. An Overview A. Classifying Organisms B. Kingdoms
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The Diversity of Life I. An Overview A. Classifying Organisms B. Kingdoms Phylogenetic analysis revealed that the "Monera" were an incredibly diverse group genetically. Also, one subgroup - the Archea, were more similar to Eukaryotes than to the other group of prokaryotes (the 'Eubacteria').
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The Diversity of Life I. An Overview A. Classifying Organisms B. Kingdoms Phylogenetic analysis revealed that the "Monera" were an incredibly diverse group genetically. Also, one subgroup - the Archea, were more similar to Eukaryotes than to the other group of prokaryotes (the 'Eubacteria'). This required a new way of looking at the most fundamental groupings of life - and the introduction of a new term: Domains
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The Diversity of Life I. An Overview A. Classifying B. Kingdoms C. Domains
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The Diversity of Life I. An Overview A. Classifying B. Kingdoms C. Domains Curiously, the very root of life may be invisible to genetic analysis. Bacteria transfer genes by division (to 'offspring'), but they also transfer genes "laterally" to other living bacteria. This makes reconstructing bacterial phylogenies difficult.
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The Diversity of Life I. An Overview A. Classifying B. Kingdoms C. Domains Also, early evolution involved bacterial symbioses and gene sharing between hosts and symbionts
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The Diversity of Life I. An Overview A. Classifying B. Kingdoms C. Domains So, reconstructing the patterns of relatedness among these ancient life forms is difficult.
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The Diversity of Life I. An Overview D. Timeline 4.5 bya: Earth Forms
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The Diversity of Life I. An Overview D. Timeline 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks
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The Diversity of Life I. An Overview D. Timeline 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils
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The Diversity of Life I. An Overview D. Timeline 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils Stromatolites - communities of layered 'bacteria'
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The Diversity of Life I. An Overview D. Timeline bya: Oxygen in Atmosphere 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils
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The Diversity of Life I. An Overview D. Timeline bya: Oxygen 1.8 bya: first eukaryote 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils
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The Diversity of Life I. An Overview D. Timeline bya: Oxygen 1.8 bya: first eukaryote 0.9 bya: first animals 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils
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The Diversity of Life I. An Overview D. Timeline bya: Oxygen 1.8 bya: first eukaryote 0.9 bya: first animals 0.5 bya: Cambrian 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils
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The Diversity of Life I. An Overview D. Timeline bya: Oxygen 1.8 bya: first eukaryote 0.9 bya: first animals 0.5 bya: Cambrian 0.24 bya:Mesozoic 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils
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The Diversity of Life I. An Overview D. Timeline bya: Oxygen 1.8 bya: first eukaryote 0.9 bya: first animals 0.5 bya: Cambrian 0.24 bya:Mesozoic 0.065 bya:Cenozoic 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils
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The Diversity of Life I. An Overview D. Timeline 4.5 million to present (1/1000th of earth history) bya: Oxygen 1.8 bya: first eukaryote 0.9 bya: first animals 0.5 bya: Cambrian 0.24 bya:Mesozoic 0.065 bya:Cenozoic 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils
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The Diversity of Life I. An Overview D. Timeline 5 million to present bya: Oxygen 1.8 bya: first eukaryote 0.9 bya: first animals 0.5 bya: Cambrian 0.24 bya:Mesozoic 0.065 bya:Cenozoic 4.5 bya: Earth Forms 4.0 bya: Oldest Rocks 3.8 bya: Oldest Fossils for 1/2 of life's history, life was exclusively bacterial.... what were they doing? Spheres, rods, and spirals were all they could come up with?? Let's look...
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