4.1.1 Biodiversity

1. 4.1.1 Biodiversity The variety of life

2. Biodiversity Whiteboard Activity • A: Everyone will be one type of tree • Douglas Fir (Write a D on your whiteb0ard) • Walk around and write down 3 peoples names on your board • Go back to you seat and remain standing • A disease will now infect one and spread among the trees • B: We will now be different trees (Repeat Steps in A) • Douglas Fir (D) • Nobel Fir (N) • Western Red Cedar (C) • Maple (M) • Hemlock (H) • White fir (W) • Lodge Pine (L) • White Pine (WP) • Western Dogwood (WD)

3. Important Terms • Biodiversity: The amount of different species living in an area. • Genetic Diversity: Different genetic characteristics of a species. • Cheetah populations have very low diversity, due to inbreeding

4. Important Terms • Species Diversity: The number of species or organisms per unit area found in different habitats of the planet.

5. Important Terms • Habitat Diversity: The amount of habitats or niches in a given area • Variety of forests, deserts, grasslands, lakes, oceans, coral reefs, wet lands, and other biological communities. Chaparral Coniferous forest dessert grasslands deciduous forest

6. Biodiversity: Why should we care? • Diverse ecosystems are more stable and more healthy • More resistant to damage from factors like climate change and spread of disease • Provides important ecological services to humans • Biodiversity is useful to us as humans • Recreation • Food • Goods • Medicine

7. Pre-Assessment Questions(Write on Loose leaf paper) • How do you think diversity changes during succession? • Do you think a more complex ecosystem is more or less stable? • How could human activities (agriculture, mining…) impact biodiversity? • What are the potential positive and negative results of human activities that reduce diversity? • How might habitat diversity impact species diversity and genetic diversity?

8. Ecological Services of Biodiversity • Flow of material, energy in the biosphere • Photosynthesis • Pollination • Soil formation and maintenance • Nutrient cycling • Moderation of weather extremes • Purification of air and water

9. Important “stuff” From biodiversity • Food, fuel, ecosystems, species, fiber, lumber, paper…. • 90% of all food crops • 40% of all medicines and 85% of all antibiotics Pacific Yew – Taxol (cancer drug) Willow Tree - Aspirin

10. Biodiversity of Species

11. 4.1.2-.5 Natural Selection

12. Darwin Natural Selection • Important Terms • Evolution: A change in the gene pool of a population over time • Natural Selection: Process by which individuals that are better suited to their environment survive and reproduce more successfully. • Adaptation: An inherited characteristic that increases an organism’s chance of survival.

13. Darwin's Research • Studies 13 species of finches on Galapagos Islands • Looked a beak size and shape: • Stout beaks for eating seeds • Short and sharp beaks for eating insects. • Woodpecker-like beak for eating insects from trees, but instead of a long tongue it uses a cactus spine held in its beak to remove its prey.

14. Darwin’s Finches

15. Darwin’s Theory • Based on his observations he proposed that the evolution of species occurs by Natural selection. • Occurred due to: • Variation within populations (Genetic Diversity) • Overproduction of offspring (J and S curves) • Struggle for existence (Competition/ Limited resources) • Unequal survival and reproduction rates (R and K)

16. Population of Organisms Overproduction of Offspring Mutations & Sexual Reproduction produces variations among offspring. Limited resources leads to a struggle for survival between offspring. Survivors reproduce more successfully. Population changes over time.

17. What is a species? • Species: A group of interbreeding populations, with a common gene pool, which are reproductively isolated. • It’s not all about looks! Different Species: They do not Interbreed, because they have different songs. Western Medowlark Eastern Medowlark

18. What is a species… • Species definition was made by humans, and fails to fully define nature. • These two ants look different are the same species of ant fulfilling different roles in a colony. Pheidolebarbata

19. Species definition is not always black and whiteAre we the same? +

20. ZONKEY

21. Are we the same? +

22. LIGER!

23. Speciation due to isolation • The islands are close enough to allow migration and cause distinct island populations to arise. • But the distances between the islands is great enough to reduce interbreeding between islands • This has made possible the formation of distinctive species on the islands Speciation in grand canyon

24. Speciation occurred on the earth over a very long period of time when the continents slowly drifted apart. This leads to geographic isolation

25. Speciation of salamanders due to geographic isolation

26. Process of Natural Selection • Organisms became isolated on various continents which restricted interbreeding populations • Without the opportunity to interbreed and the slowly changing climatic conditions organisms “evolve” into a new species over time. • This leads to “survival of the fittest” • Fitness: Organisms that are better suited to survive and reproduce

27. Discussion Question • Why does Australia have such strange animals??

28. Evolutionary Timeline of mammals Platypus (Monotreme) Dingo (Placental Mammal) Kangaroo (Marsupial)