1. The Cenozoic Era 1.8 5.0 23.7 33.5 54.5 66.4 Ma

2. Major themes of the Cenozoic Earth –overall climatic cooling (“greenhouse to icehouse”) –changes in ocean circulation –Pangea breakup continues but slows –changes in position of land and sea –changes in oceanic nutrient levels Life –diversification and dominance of mammals –dominance of angiosperms –continuation of the Mesozoic Marine Revolution

3. The Earth in the Cenozoic Changes in position of land and sea –destruction of Tethys –effects on climate –effects on ocean circulation –land bridges Changes in ocean circulation –cooling  more vigorous circulation –continental position  new current patterns Overall climatic cooling –continental position  S. Hemisph. glaciation

7. Glomar Challenger JOIDES Resolution The Deep Sea Drilling / Ocean Drilling Project (DSDP/ODP)

15. Oxygen isotope paleothermometry O isotope fractionation is temperature- dependent (warmer temps  more 16 O, less 18 O) expressed as ppt relative to PDB (Pee Dee Belemnite) need to correct for ice volume (more glacial ice  SW enriched in 18 O)

17. Oxygen isotope paleothermometry  18 O negative = warmer  18 O positive = cooler

18. Major climate events of the Cenozoic Late Paleocene Thermal Maximum (LPTM) Eocene-Oligocene cooling / Antarctic glaciation Miocene cooling Pleistocene glaciation

21. The carbon isotopic excursion at the P-E boundary

22. Possible cause(s) for the LPTM more hydrothermal activity  more CO 2  warming  release of methane clathrates  more CO 2  warming

23. Methane Hydrates

26. Major climate events of the Cenozoic Late Paleocene Thermal Maximum (LPTM) Eocene-Oligocene cooling / Antarctic glaciation Miocene cooling Pleistocene glaciation

29. The breakup of Gondwanaland: the death of Tethys and the formation of the Circumantarctic Current India collides with southern Asia (ca. 55 Ma) Australia separates from Antarctica (ca. 58 Ma) South America separates from Antarctica -- the Drake Passage (33.5-23.5 Ma)

35. Major climate events of the Cenozoic Late Paleocene Thermal Maximum (LPTM) Eocene-Oligocene cooling / Antarctic glaciation Miocene cooling Pleistocene glaciation

38. The rise of mammals

40. Eocene Miocene

44. The evolution of whales

49. http://www.indiana.edu/~ensiweb/images/whal.amb.jpeg

50. An artist's rendering of Rodhocetus. This mammal lived near the shores of the Tethys Sea, between Asia and the South Asian subcontinent, about 47 million years ago.

51. The real fossil bones of the walking and swimming whale, Ambulocetus natans, are spread out in this picture with a sledgehammer for scale. The skeleton was about 12 feet long and is about 49 million years old. It was found in Pakistan.

52. Basilosaurus, Eocene of Alabama