TERTIARY TO PRESENT/Miocene 485 sequestered in the plant tissues This compound can then be broken down and the CO2 passed to Rubisco away from the presence of oxygen, so that little photorespiration can occur Chalicotheres An extinct group of perissodactyls, in the family Chalicotheriidae These animals were very large, with clawed feet Some had very long forelimbs, and were probably bipedal, feeding on leaves from tall trees They are known from the latest Eocene up to the Pleistocene Creodont carnivore The creodonts are an extinct group of carnivorous mammals It was long thought that they were ancestral to the modern order Carnivora, but more recent work indicates they may not be close relatives They looked somewhat dog-like, with slicing carnassial teeth similar to those of Carnivora However, in Carnivora the carnassial teeth are the last upper premolar and first lower molar, and in creodonts the carnassial teeth are the upper first and/or second molars and the lower second or third molar Rain shadow Dry region on the leeward side of a mountain or mountain range The rain shadow effect is caused when moist air rises against the windward slope and is lost to precipitation on the windward side, leaving little moisture on the leeward side Ungulate Hoofed mammals, such as the ariodactyls (cows, pigs, sheep, deer, etc.) or perissodactyls (horses, rhinos) The last phalanx, or ungual phalanx, of each toe in ungulates is modified with a thick hoof instead of a claw Viverrids The members of the extant carnivoran family Viverridae, the civets and mongoose, known today in Africa and Asia Viverrids are small, arboreal and generally fruit-eaters Waif dispersal An unusual form of inter-continental dispersal across large bodies of water by terrestrial animals In an episode of waif dispersal, one or several animals inadvertently travels between two continents on vegetation rafts, and populates the new region on arrival Waif dispersal may be responsible for the arrival of monkeys into South America See Also Analytical Methods: Geochronological Techniques Andes Atmosphere Evolution Europe: Mediterranean Tectonics Famous Geologists: Suess Fossil Vertebrates: Mesozoic Mammals; Placental Mammals; Hominids Indian Subcontinent Stratigraphical Principles Tertiary To Present: Oligocene; Pliocene Further Reading Berggren WA, Kent DV, Swisher CC III, and Aubry M P (1995) A revised Cenozoic geochronology and chron ostratigraphy In: Berggren WA, Kent DV, Aubry M P, and Hardenbol J (eds.) Geochronology, Time Scales, and Global Stratigraphic Correlation: Unified Temporal FrameWork for an Historical Geology, pp 129 212 Tulsa: Society for Sedimentary Geology SEPM Special Publication 54 Flower BJ and Kennett JP (1993) Middle Miocene ocean climate transition: high resolution oxygen and carbon isotopic records from Deep Sea Drilling Project site 588A, southwest Pacific Paleoceanography 8: 811 843 Jackson JBC, Budd AF, and Coates AG (eds.) (1996) Evolu tion and Environment in Tropical America Chicago: University of Chicago Press Jacobs BF, Kingston JD, and Jacobs LL (1999) The Origin of Grass Dominated Ecosystems Annals of the Missouri Botanical Garden 86: 590 643 Janis CM, Scott KM, and Jacobs LL (eds.) (1998) Evolution of Tertiary Mammals of North America: Volume Terrestrial Carnivores, Ungulates, and Ungulatelike Mammals Cambridge: Cambridge University Press Miller KG, Wright JD, and Fairbanks RG (1991) Unlocking the icehouse: Oligocene Miocene oxygen isotopes, eu stasy, and margin erosion Journal of Geophysical Research 96(B4): 6829 6848 Pazzaglia FJ and Kelley SA (1998) Large scale geo morphology and fission track thermochronology in topographic exhumation reconstructions of the Southern Rocky Mountains Rocky Mountain Geology 33(2): 229 257 Raymo ME (1994) The Himalayas, organic carbon burial, and climate in the Miocene Paleogeography 9: 352 404 Roă ssner GE and Heissig K (eds.) (1999) The Miocene Land Mammals of Europe Munich: Verlag Dr Friedrich Pfeil Scotese CR, Gahagan LM, and Larson RL (1989) Plate tectonic reconstructions of the Cretaceous and Cenozoic ocean basins Tectonophys 155: 27 48 Vickers Rich P, Monaghan JM, Baird RF, and Rich TH (eds.) (1991) Vertebrate Paleontology of Australasia Melbourne: Pioneer Design Studio Woodburne MO (ed.) (1987) Cenozoic Mammals of North America: Geochronology and Biostratigraphy Berkeley: University of California Press Zachos JC, Pagani M, Sloan L, Thomas E, and Billups K (2001) Trends, rhythms, and aberrations in global cli mate 65 Ma to present Science 292: 686 693