1. Wednesday October 27, 2010 (The Phanerozoic Eon)

2. The Launch Pad Wednesday, 10/27/10 The beginning of the Cambrian period marks an important event in animal evolution, the appearance of organisms with __________________. A.wings B.cells C.shells and other hard parts D.vertebrae E.none of the above

3.  If you need to take or remediate Test 3, please make an appointment with me to do so ASAP.

4. Assignment Currently Open Pages Date of Notes on Website Date IssuedDate Due

6. The Phanerozoic Eon The Phanerozoic Eon encompasses 542 million years, and is still the current Eon. The Phanerozoic Eon is divided into the Paleozoic, Mesozoic, and Cenozoic Eras.

7. The Phanerozoic Eon The Paleozoic Era The Paleozoic Era was dominated by continental collisions as Pangaea began to assemble.

8. The Phanerozoic Eon The Paleozoic Era At this time the Caledonian, Appalachian, and Ural Mountains were formed.

9. The Phanerozoic Eon The Paleozoic Era The early Paleozoic Era consisted of the Cambrian and Ordovician Periods. This was known as the “Age of Invertebrates.”

10. The Phanerozoic Eon The Paleozoic Era The middle Paleozoic Era consisted of the Silurian and Devonian Periods. This was known as the “Age of Fishes.”

11. The Phanerozoic Eon The Paleozoic Era The later Paleozoic Era consisted of the Carboniferous Mississippian, Carboniferous Pennsylvanian, and Permian Periods. This was known as the “Age of Amphibians.”

12. The Paleozoic Era: Life Explodes The Paleozoic Era marks the first appearance of life-forms with hard parts such as shells. Life in the early Paleozoic was restricted to the seas and consisted of several invertebrate groups including: This development resulted in abundant Paleozoic fossils. Trilobites Cephalopods Sponges Corals

13. Paleozoic Marine Invertebrates Figure 12.26

14. The Paleozoic Era: Life Explodes During the Paleozoic, organisms diversified dramatically. Insects and plants moved onto land. Lobe-finned fishes adapted to land and became the first amphibians. Large tropical swamps in the Pennsylvanian period became the major coal deposits of today.

15. Figure 12.28

16. Figure 12.27

17. Pennsylvanian-Age Coal Swamp Figure 12.29

18. The Paleozoic Era: Life Explodes A mass extinction at the close of the Paleozoic Era destroyed 70% of all vertebrate species on land and 90% of all marine organisms.

19. Figure 12.A (left)

20. Figure 12.A (right)

21. The Phanerozoic Eon The Mesozoic Era Early in the Mesozoic Era, much of the land was above sea level. By the middle Mesozoic, seas invaded western North America. Pangaea began to break apart and the westward-moving North American plate began to override the Pacific plate. This resulted in crustal deformation along the entire western margin of North America. The Sierra Nevada and Rocky Mountains were formed at this time.

22. The Phanerozoic Eon The Mesozoic Era The Mesozoic Era was known as the “Age of Reptiles.” The early Mesozoic Era consisted of the Triassic Period.

23. The Mesozoic Era: Age of the Reptiles The Mesozoic, literally the era of middle life, is often called the “Age of Reptiles.” By the way, dinosaurs were not lizards!

24. Formation of the Pangaea supercontinent Figure 12.19 D

25. The Mesozoic Era: Age of the Reptiles Organisms that survived the extinction at the end of the Paleozoic began to diversify.

26. The Mesozoic Era: Age of the Reptiles Gymnosperms (cycads, conifers, and ginkgoes) became the dominant trees of the Mesozoic.

27. The Mesozoic Era: Age of the Reptiles Reptiles became the dominant land animals.

28. Mesozoic Era: Age of the Reptiles The first reptiles were small, but evolved rapidly, particularly the dinosaurs.

29. Diversity of reptiles included: The Mesozoic Era: Age of the Reptiles large herbivorous dinosaurs such as Apatosaurus large carnivorous dinosaurs such as Allosaurus Pterosaurs or flying reptiles and Archaeopteryx, the predecessor of modern birds

30. Archaeopteryx fossil

31. Ichthyosaur Fossil

32. Figure 12.C-B

33. The Phanerozoic Eon The Mesozoic Era The Mesozoic Era was known as the “Age of Reptiles.” The middle Mesozoic Era consisted of the Jurassic Period.

34. The Phanerozoic Eon The Mesozoic Era The Mesozoic Era was known as the “Age of Reptiles.” The late Mesozoic Era consisted of the Cretaceous Period.

35. A few types survived, including the turtles, snakes, and lizards The Mesozoic Era: Age of the Reptiles At the close of the Mesozoic Era, many reptile groups became extinct.

36. The Phanerozoic Eon The Cenozoic Era Much of North America was above sea level throughout the Cenozoic Era. Eastern and Western margins of the continent experienced markedly contrasting events. Atlantic and Gulf coastal regions, removed from active plate boundaries, were tectonically stable. In the West, the Laramide orogeny (Rocky Mountains) was ending, the Basin and Range Province was forming, and volcanic activity was extensive.

37. The Phanerozoic Eon The Cenozoic Era In the Cenozoic, mammals replaced the reptiles as the dominant vertebrate life-forms on land. Two groups of mammals evolved, the marsupials and the placentals. One tendency was for some mammal groups to become very large. Late Pleistocene extinctions eliminated these larger animals.

38. Figure 12.35 marsupial

39. placental

40. The Phanerozoic Eon The Cenozoic Era The Cenozoic could also be called the “Age of Flowering Plants.” Flowering plants (angiosperms) strongly influenced the evolution of both birds and herbivorous mammals throughout the Cenozoic.

41. Figure 12.34A