1. Evolution and Biodiversity: Origins, Niches, and Adaptation G. Tyler Miller, Jr.’s Environmental Science 10 th Edition Chapter 5 G. Tyler Miller, Jr.’s Environmental Science 10 th Edition Chapter 5

2. Key Concepts  Origins of life  Evolution and Evolutionary processes  Ecological niches  Species formation  Species extinction

3. Earth: Just-right Resilient Planet DO NOT POST TO INTERNET Fig. 5-1, p. 92  Temperature  Liquid water  Rotation  Size and gravity  Ozone layer  Life

4. Origins and Early Evolution of Life  Chemical evolution  Biological evolution Fig. 5-2 p. 93

5. Plants begin invading land Evolution and expansion of life First fossil record of animals Plants invade the land Age of reptiles Age of mammals Insects and amphibians invade the land Modern humans (Homo sapiens) appear about 2 seconds before midnight Recorded human history begins 1/4 second before midnight Origin of life (3.6–3.8 billion years ago) noon midnight Fig. 5-3, p. 94 Biological Evolution Over Geologic Time

6. Biological Evolution  Theory of Evolution  Evolution  Microevolution  Macroevolution

7. Microevolution  Alleles  Gene pool  Mutations  Natural selection

8. Natural Selection  Differential reproduction  Adaptive trait (adaptation)  Artificial selection  Coevolution

9. Peppered Moths and Adaptation Fig. 5-4, p. 96

10. Natural selection New averagePrevious average Number of individuals Coloration of snails Proportion of light-colored snails in population increases Number of individuals Snail coloration best adapted to conditions Average Coloration of snails Average shifts Figure 5-5a, p. 97 Directional Natural Selection

11. Coloration of snails Light snails eliminated Dark snails eliminated Number of individuals Coloration of snails Snails with extreme coloration are eliminated Number of individuals Average remains the same, but the number of individuals with intermediate coloration increases Natural selection Fig. 5-5b, p. 97 Stabilizing Natural Selection

12. Number of individuals with light and dark coloration increases, and the number with intermediate coloration decreases Coloration of snails Number of individuals Snails with light and dark colors dominate Coloration of snails Number of individuals Light coloration is favored Dark coloration is favored Intermediate-colored snails are selected against Natural selection Fig. 5-5c, p. 97 Diversifying Natural Selection

13. Ecological Niches and Adaptation Fig. 5-6 p. 98  Ecological niche  Habitat  Fundamental niche  Realized niche

14. Broad and Narrow Niches and the Limits of Adaptation  Generalist species  Specialist species Refer to Spotlight p. 99  Limits of Adaptation

15. Specialized Feeding Niches for Birds Black skimmer seizes small fish at water surface Flamingo feeds on minute organisms in mud Scaup and other diving ducks feed on mollusks, crustaceans, and aquatic vegetation Brown pelican dives for fish, which it locates from the air Avocet sweeps bill through mud and surface water in search of small crustaceans, insects, and seeds Louisiana heron wades into water to seize small fish Oystercatcher feeds on clams, mussels, and other shellfish into which it pries its narrow beak Dowitcher probes deeply into mud in search of snails, marine worms, and small crustaceans Knot (a sandpiper) picks up worms and small crustaceans left by receding tide Herring gull is a tireless scavenger Ruddy turnstone searches under shells and pebbles for small invertebrates Piping plover feeds on insects and tiny crustaceans on sandy beaches Fig. 5-7, p. 100-101

16. Misconceptions about Evolution  “Survival of the fittest”  “Progress to perfection”

17. Speciation, Extinction, and Biodiversity  Speciation  Geographic isolation  Reproductive isolation Fig. 5-8, p.100

18. Factors Affecting Speciation and Extinction  Plate tectonics  Climate changes over time  Natural catastrophes  Human Impacts

19. Extinction and Recovery  Background extinction  Mass extinction  Adaptive radiation  Mass depletion  Human Impacts

20. EURASIA AFRICA SOUTH AMERICA INDIA 135 million years ago Present 65 million years ago 225 million years ago 120°80°0° 120° 80° 40° 120° GONDWANALAND 120° LAURASIA PANGAEA ANTARCTICA AUSTRALIA NORTH AMERICA MADA- GASCAR MADA- GASCAR Fig. 5-9, p. 101 “Continental Drift” (Plate Tectonics): The Breakup of Pangaea

21. Impact of Speciation and Extinction on Biodiversity  “Biodiversity = Speciation – Extinction”  Human impacts on extinction and biodiversity  Recovery of biodiversity  Genetic engineering  “Biodiversity = Speciation – Extinction”  Human impacts on extinction and biodiversity  Recovery of biodiversity  Genetic engineering