Evolving between land and water: Key questions on the emergence and history of the hippopotamidae (hippopotamoidea, cetancodonta, cetartiodactyla)

Biological Reviews

Volumn 86, Issue 3, 2011, Pages 601-625

  Boisserie, Jean Renaud ^a,b   Fisher, Rebecca E ^c,d   Lihoreau, Fabrice ^e   Weston, Eleanor M ^f  

^a Centre National de la Recherche Scientifique Unité de Service et de Recherche 3137   (Ethiopia)

^b UNIVERSITÉ DE POITIERS   (France)

^c UNIVERSITY OF ARIZONA COLLEGE OF MEDICINE   (United States)

^d ARIZONA STATE UNIVERSITY   (United States)

^e UNIV MONTPELLIER   (France)

^f DEPARTMENT OF LIFE SCIENCES   (United Kingdom)

Author keywords

Africa; Artiodactyl paraphyly; Biogeography; Environmental changes; Insular evolution; Neogene; Parallelism; Phylogeny; Semiaquatic adaptations

Indexed keywords

ANIMAL; ARTICLE; ARTIODACTYLA; CLASSIFICATION; ECOSYSTEM; EVOLUTION; FOSSIL; GENETICS; HISTOLOGY;

ANIMALS; ARTIODACTYLA; BIOLOGICAL EVOLUTION; ECOSYSTEM; FOSSILS;

ANTHRACOTHERIIDAE; ARTIODACTYLA; CETACEA; CETARTIODACTYLA; HIPPOPOTAMIDAE; MAMMALIA;

EID: 79960434258     PISSN: 14647931     EISSN: 1469185X     Source Type: Journal    
DOI: 10.1111/j.1469-185X.2010.00162.x     Document Type: Article

References (233)

1. Agnarsson, I. & May-Collado, L. J. (2008). The phylogeny of Cetartiodactyla: the importance of dense taxon sampling, missing data, and the remarkable promise of cytochrome b to provide reliable species-level phylogenies. Molecular Phylogenetics and Evolution 48, 964-985.
2. Agustí, J., Garcés, M. & Krijgsman, W. (2006). Evidence for African-Iberian exchanges during the Messinian in the Spanish mammalian record. Palaeogeography, Palaeoclimatology, Palaeoecology 238, 5-14.
3. Alemseged, Z. (1998). L'hominidé Omo-323: sa position phylétique et son environnement dans le cadre de l'évolution des communautés de mammifères du Plio-Pléistocène dans la basse vallée de l'Omo (Ethiopie). Thèse NC thesis, Muséum National d'Histoire Naturelle.
4. Andrews, C. W. (1906). A descriptive catalogue of the Tertiary Vertebrata of the Fayûm, Egypt. British Museum (Natural History), London.
5. Arnason, U., Gullberg, A. & Janke, A. (2004). Mitogenomic analyses provide new insights into cetacean origin and evolution. Gene 333, 27-34.
6. Arnason, U., Gullberg, A., Solweig, G., Ursing, B. & Janke, A. (2000). The mitochondrial genome of the sperm whale and a new molecular reference for estimating eutherian divergence rate. Journal of Molecular Evolution 50, 569-578.
7. Badgley, C. (2009). Tectonic history and mammalian diversity. Journal of Vertebrate Paleontology 29, 57.
8. Bajpai, S. & Gingerich, P. D. (1998). A new Eocene archaeocete (Mammalia, Cetacea) from India and the time of origin of whales. Proceedings of the National Academy of Sciences of the United States of America 95, 15464-15468.
9. Behrensmeyer, A. K. (2006). Climate change and human evolution. Science 311, 476-478.
10. Behrensmeyer, A. K., Bobe, R. & Alemseged, Z. (2007). Approaches to the analysis of faunal change during the East African Pliocene. In Hominin Environments in the East African Pliocene (ed. R. Bobe, Z. Alemseged and A. K. Behrensmeyer), pp. 1-24. Springer, Dordrecht.
11. Behrensmeyer, A. K., Deino, A. L., Hill, A., Kingston, J. D. & Saunders, J. J. (2002). Geology and geochronology of the middle Miocene Kipsaramon site complex, Muruyur Beds, Tugen Hills, Kenya. Journal of Human Evolution 42, 11-38.
12. Benton, M. J., Donoghue, P. C. J. & Asher, R. J. (2009). Calibrating and constraining molecular clocks. In The Timetree of Life (ed. S. B. Hedges and S. Kumar), pp. 35-86. Oxford University Press, Oxford.
13. Black, C. A. (1978). Anthracotheriidae. In Evolution of African Mammals (ed. V. J. Maglio and H. B. S. Cooke), pp. 423-434. Harvard University Press, Cambridge.
14. Bobe, R., Alemseged, Z. & Behrensmeyer, A. K. (2007). Hominin environments in the East African Pliocene. Springer, Dordrecht.
15. Boekschoten, G. J. & Sondaar, P. Y. (1972). On the fossil Mammalia of Cyprus. Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen 75, 306-338.
16. Boisserie, J.-R. (2005). The phylogeny and taxonomy of Hippopotamidae (Mammalia: Artiodactyla): a review based on morphology and cladistic analysis. Zoological Journal of the Linnean Society 143, 1-26.
17. Boisserie, J.-R. (2006). Langebaanweg: a unique window on early hippopotamid evolution in southern Africa. African Natural History 2, 181-182.
18. Boisserie, J.-R. (2007). Family Hippopotamidae. In The evolution of artiodactyls (ed. D. R. Prothero and S. E. Foss), pp. 106-119. Johns Hopkins University Press, Baltimore.
19. Boisserie, J.-R. & Lihoreau, F. (2006). Emergence of Hippopotamidae: new scenarios. Comptes Rendus Palevol 5, 749-756.
20. Boisserie, J.-R., Lihoreau, F. & Brunet, M. (2005a). Origins of Hippopotamidae (Mammalia, Cetartiodactyla): towards resolution. Zoologica Scripta 34, 119-143.
21. Boisserie, J.-R., Lihoreau, F. & Brunet, M. (2005b). The position of Hippopotamidae within Cetartiodactyla. Proceedings of the National Academy of Sciences of the United States of America 102, 1537-1541.
22. Boisserie, J.-R., Lihoreau, F., Orliac, M., Fisher, R. E., Weston, E. M. & Ducrocq, S. (2010). Morphology and phylogenetic relationships of the earliest known hippopotamids (Cetartiodactyla, Hippopotamidae, Kenyapotaminae). Zoological Journal of the Linnean Society 158, 325-366.
23. Boisserie, J.-R., Likius, A., Vignaud, P. & Brunet, M. (2005c). A new late Miocene hippopotamid from Toros-Ménalla, Chad. Journal of Vertebrate Paleontology 25, 665-673.
24. Boisserie, J.-R. & White, T. D. (2004). A new species of Pliocene Hippopotamidae from the Middle Awash, Ethiopia. Journal of Vertebrate Paleontology 24, 464-473.
25. Boisserie, J.-R., Zazzo, A., Merceron, G., Blondel, C., Vignaud, P., Likius, A., Mackaye, H. T. & Brunet, M. (2005d). Diets of modern and late Miocene hippopotamids: evidence from carbon isotope composition and micro-wear of tooth enamel. Palaeogeography, Palaeoclimatology, Palaeoecology 221, 153-174.
26. Bonarelli, G. (1946). Dinosauro fossile del Sahara Cirenaico. Rivista di Biologia Coloniale 7, 23-33.
27. Bouvrain, G. & Bonis, L. d. (1999). Suoidea du Miocène inférieur de Laugnac (Lot-et-Garonne, France). Paläontologische Zeitschrift 73, 167-178.
28. Brown, P., Sutikna, T., Morwood, M. J., Soejono, R. P., Jatmiko, Wayhu, S. E. & Due, R. A. (2004). A new small-bodied hominin from the late Pleistocene of Flores, Indonesia. Nature 431, 1055-1061.
29. Calandra, I., Göhlich, U. B. & Merceron, G. (2008). How could sympatric megaherbivores coexist? Example of niche partitioning within a proboscidean community from the Miocene of Europe. Naturwissenschaften 95, 831-838.
30. Caloi, L. & Palombo, M. R. (1994). Functional aspects and ecological implications in Pleistocene endemic herbivores of mediterranean islands. Historical Biology 8, 151-172.
31. Cerling, T. E., Harris, J. M., Hart, J. A., Kaleme, P., Klingel, H., Leakey, M. G., Levin, N. E., Lewison, R. L. & Passey, B. H. (2008). Stable isotope ecology of the common hippopotamus. Journal of Zoology 276, 204-212.
32. Cerling, T. E., Harris, J. M. & Leakey, M. G. (2003). Isotope paleoecology of the Nawata and Nachukui Formations at Lothagam, Turkana Basin, Kenya. In Lothagam. The dawn of humanity in eastern Africa (ed. J. M. Harris and M. G. Leakey), pp. 587-597. Columbia University Press, New York.
33. Chorowicz, J. (2005). The East African rift system. Journal of African Earth Sciences 43, 379-410.
34. Clementz, M. T., Goswami, A., Gingerich, P. D. & Koch, P. L. (2006). Isotopic records from early whales and sea cows: contrasting patterns of ecological transition. Journal of Vertebrate Paleontology 26, 355-370.
35. Clementz, M. T., Holroyd, P. A. & Koch, P. L. (2008). Identifying aquatic habits of herbivorous mammals through stable isotope analysis. PalaÏos 23, 574-585.
36. Colbert, E. H. (1935). The phylogeny of the Indian Suidae and the origin of the Hippopotamidae. American Museum Novitates 799, 1-24.
37. Colosimo, P. F., Hosemann, K. E., Balabhadra, S., Villarreal, G. J., Dickson, M., Grimwood, J., Schmutz, J., Myers, R. M., Schluter, D. & Kingsley, D. M. (2005). Widespread parallel evolution in sticklebacks by repeated fixation of ectodysplasin alleles. Science 307, 1928-1933.
38. Coombs, M. C. & Coombs, W. P. Jr (1977). Dentition of Gobiohyus and a reevaluation of the Helohyidae (Artiodactyla). Journal of Mammalogy 58, 291-308.
39. Coombs, W. P. Jr & Coombs, M. C. (1977). The origin of anthracotheres. Neues Jahrbuch für Geologie und Paläontologie, Monatshefte 10, 584-599.
40. Coryndon, S. C. (1971). Evolutionnary trends in East African Hippopotamidae. Bulletin de l'Association française pour l'Etude du Quaternaire, 473-478.
41. Coryndon, S. C. (1972). Hexaprotodont Hippopotamidae of East Africa and the phylogeny of the family. In Actes du 6°Congrès Panafricain de Préhistoire, Dakar 1967, pp. 350-352. Les imprimeries réunies, Chambéry.
42. Coryndon, S. C. (1978). Hippopotamidae. In Evolution of African Mammals (ed. V. J. Maglio and H. B. S. Cooke), pp. 483-495. Harvard University Press, Cambridge.
43. Coryndon, S. C. & Coppens, Y. (1975). Une espèce nouvelle d'hippopotame nain du Plio-Pléistocène du bassin du lac Rodolphe (Ethiopie, Kenya). Comptes Rendus de l'Académie des Sciences 280, 1777-1780.
44. Cuvier, G. (1822). Recherches sur les ossemens fossiles. Edmond d'Ocagne éditeur, Paris.
45. de Queiroz, A. & Gatesy, J. (2007). The supermatrix approach to systematics. Trends in Ecology and Evolution 22, 34-41.
46. Dennell, R. W. (2005). Early Pleistocene hippopotamid extinctions, monsoonal climates, and river system histories in South and South-West Asia: comment on Jablonski (2004) Quaternary International 117, 119-123. Quaternary International 126-128, 283-287.
47. Denys, C., Chorowicz, J. & Tiercelin, J. J. (1986). Tectonic and environmental control on rodent diversity in the Plio-Pleistocene sediments of the African Rift system. In Sedimentation in the African rifts, vol. 25 (ed. L. E. Frostick, R. W. Renaut, I. Reid and J. J. Tiercelin), pp. 363-372.
48. Deocampo, D. M. (2002). Sedimentary structures generated by Hippopotamus amphibius in a lake-margin wetland, Ngorongoro Crater, Tanzania. PalaÏos 17, 212-217.
49. Domning, D. P. (2001). The earliest known fully quadrupedal sirenian. Nature 413, 625-627.
50. Drake, N. A., El-Hawat, A. S. & Salem, M. J. (2008). The development, decline and demise of the As Sahabi river system over the last seven million years. In Circum-Mediterranean geology and biotic evolution during the Neogene period: the perspective from Libya, vol. Special Issue 5 (ed. N. T. Boaz, A. El-Arnauti, P. P. Pavlakis and M. J. Salem), pp. 95-109. University of Garyounis G. S. P. L. A. J., Benghazi.
51. Ducrocq, S. (1999). The late Eocene Anthracotheriidae (Mammalia, Artiodactyla) from Thailand. Palaeontographica Abteilung A 252, 93-140.
52. Ducrocq, S., Chaimanee, Y., Suteethorn, V. & Jaeger, J.-J. (1997). First discovery of Helohyidae (Artiodactyla, Mammalia) in the Late Eocene of ThaÏland: a possible transitional form for Anthracotheriidae. Comptes Rendus de l'Académie des Sciences 325, 367-372.
53. Ducrocq, S., Chaimanee, Y., Suteethorn, V. & Jaeger, J. J. (2003). Occurrence of the anthracotheriid Brachyodus (Artiodactyla, Mammalia) in the early Middle Miocene of Thailand. Comptes Rendus Palevol 2, 261-268.
54. Ellery, W. N., Dahlberg, A. C., Strydom, R., Neal, M. J. & Jackson, J. (2003). Diversion of water flow from a floodplain wetland stream: an analysis of geomorphological setting and hydrological and ecological consequences. Journal of Environmental Management 68, 51-71.
55. Eltringham, S. K. (1999). The hippos. Academic Press, London.
56. Eronen, J. T., Mirzale Ataabadi, M., Micheels, A., Karme, A., Bernor, R. L. & Fortelius, M. (2009). Distribution history and climatic controls of the late Miocene Pikermian chronofauna. Proceedings of the National Academy of Sciences of the United States of America 106, 11867-11871.
57. Falconer, H. & Cautley, P. T. (1836). Note on the fossil hippopotamus of the Siwalik Hills. Asiatic Research Calcutta 19, 39-53.
58. Falconer, H. & Cautley, P. T. (1847). Fauna antiqua sivalensis, London.
59. Faure, M. (1994). Les Hippopotamidae (Mammalia, Artiodactyla) du rift occidental (bassin du lac Albert, Ouganda). Etude Préliminaire. In Geology and Paleobiology of the Albertine Rift Valley, Uganda-ZaÏre. II: Paleobiology., vol. 2 (ed. B. Senut and M. Pickford), pp. 321-337. Cifeg, Orléans.
60. Fisher, R. E., Scott, K. M. & Adrian, B. (2010). Hind limb myology of the common hippopotamus, Hippopotamus amphibius (Artiodactyla: Hippopotamidae). Zoological Journal of the Linnean Society 158, 661-682.
61. Fisher, R. E., Scott, K. M. & Naples, V. L. (2007). Forelimb myology of the pygmy hippopotamus (Choeropsis liberiensis). The Anatomical Record 290, 673-693.
62. Foss, S. E. (2007). Family Helohyidae. In The evolution of artiodactyls (ed. D. R. Prothero and S. E. Foss), pp. 85-88. The Johns Hopkins University Press, Baltimore.
63. Foss, S. E. & Prothero, D. R. (2007). Introduction. In The evolution of artiodactyls (ed. D. R. Prothero and S. E. Foss), pp. 1-3. The Johns Hopkins University Press, Baltimore.
64. 4 grassland expansions during the early Pliocene at Langebaanweg, South Africa. Paleobiology 28, 378-388.
65. Gatesy, J. (1997). More DNA support for a Cetacea/Hippopotamidae clade: the blood-clotting protein gene y-fibrinogen. Molecular Biology and Evolution 14, 537-543.
66. Gatesy, J. (1998). Molecular evidence for the phylogenetic affinities of Cetacea. In The emergence of whales (ed. J. G. M. Thewissen), pp. 63-111. Plenum Press, New York.
67. Gatesy, J. (2009). Whales and even-toed ungulates (Cetartiodactyla). In The Timetree of Life (ed. S. B. Hedges and S. Kumar), pp. 511-515. Oxford University Press, Oxford.
68. Gatesy, J., Matthee, C., Desalle, R. & Hayashi, C. (2002). Resolution of a supertree/supermatrix paradox. Systematic Biology 51, 652-664.
69. Gatesy, J. & O'Leary, M. A. (2001). Deciphering whale origins with molecules and fossils. Trends in Ecology and Evolution 16, 562-570.
70. Gaziry, A. W. (1987). Hexaprotodon sahabiensis (Artiodactyla, Mammalia): a new hippopotamus from Libya. In Neogene paleontology and geology of Sahabi (ed. B. N. T., A. El-Arnauti, A. W. Gaziry, J. d. Heinzelin and D. Dechant Boaz), pp. 303-315. Alan R. Liss, Inc., New York.
71. Geisler, J. (2001). New morphological evidence for the phylogeny of Artiodactyla, Cetacea, and Mesonychidae. American Museum Novitates 40, 1-53.
72. Geisler, J. & Bolortsetseg, M. (2009). Linking character states: a means to achive progressive morphological phylogenetics. Journal of Vertebrate Paleontology 29, 103-104.
73. Geisler, J. H. & Luo, Z. (1998). Relationships of Cetacea to terrestrial ungulates and the evolution of cranial vasculature in Cete. In The emergence of whales (ed. J. G. M. Thewissen), pp. 163-212. Plenum Press, New York.
74. Geisler, J. H. & Theodor, J. M. (2009). Hippopotamus and whale phylogeny. Nature 458, E1-E4.
75. Geisler, J. H., Theodor, J. M., Uhen, M. D. & Foss, S. E. (2007). Phylogenetic relationships of cetaceans to terrestrial artiodactyls. In The evolution of artiodactyls (ed. D. R. Prothero and S. E. Foss), pp. 19-31. The Johns Hopkins University Press, Baltimore.
76. Geisler, J. H. & Uhen, M. D. (2003). Morphological support for a close relationship between hippos and whales. Journal of Vertebrate Paleontology 23, 991-996.
77. Geisler, J. H. & Uhen, M. D. (2005). Phylogenetic relationships of extinct cetartiodactyls: results of simultaneous analyses of molecular, morphological, and stratigraphic data. Journal of Mammalian Evolution 12, 145-160.
78. Gentry, A. W. & Hooker, J. J. (1988). The phylogeny of the Artiodactyla. In The phylogeny and classification of the Tetrapods, Volume 2: Mammals, vol. 35B. Systematics Association Special Volume (ed. M. J. Benton), pp. 235-272. Clarendon Press, Oxford.
79. Gèze, R. (1980). Les Hippopotamidae (Mammalia, Artiodactyla) du Plio-Pléistocène de l'Ethiopie. Thèse de 3° cycle NC thesis, Université Pierre et Marie Curie - Paris VI.
80. Gèze, R. (1985). Répartition paléoécologique et relations phylogénétiques des Hippopotamidae (Mammalia, Artiodactyla) du néogène d'Afrique Orientale. In L'environnement des hominidés au Plio-Pléistocène (ed. M. Beden, A. K. Behrensmeyer, N. T. Boaz, R. Bonnefille, C. K. Brain, B. Cooke, Y. Coppens, R. Dechamps, V. Eisenmann, A. W. Gentry, D. Geraads, R. Gèze, C. Guérin, J. M. Harris, J. Koeniguer, F. Letouzey, G. Petter, A. Vincens and E. Vrba), pp. 81-100. Fondation Singer-Polignac Masson, Paris.
81. Gingerich, P. D. (2003). Land-to-sea transition in early whales: evolution of Eocene Archaeoceti (Cetacea) in relation to skeletal proportions and locomotion of living semiaquatic mammals. Paleobiology 29, 429-454.
82. Gingerich, P. D., Haq, M. U., Zalmout, I. S., Hussain, K. I. & Malkani, M. S. (2001). Origin of whales from early artiodactyls: hand and feet of Eocene Protocetidae from Pakistan. Science 293, 2239-2242.
83. Gingerich, P. D. & Russell, D. E. (1981). Pakicetus inachus, a new archaeocete (Mammalia, Cetacea) from the Early-Middle Eocene Kuldana formation of Kohat (Pakistan). Contributions from the Museum of Paleontology 25, 235-246.
84. Gingerich, P. D., ul-Haq, M., von Koenigswald, W., Sanders, W. J., Smith, B. H. & Zalmout, I. S. (2009). New protocetid whale from the middle Eocene of Pakistan: birth on land, precocial development, and sexual dimorphism. Plos One 4, 1-20.
85. Ginsburg, L. (1980). Xenohyus venitor, suidé nouveau (Mammalia, Artiodactyla) du Miocène inférieur de France. Géobios 13, 861-877.
86. Gould, S. J. (1975). On the scaling of tooth size in mammals. American Zoologist 15, 351-362.
87. Gould, S. J. (2002). The structure of evolutionary theory. Harvard University Press, New York.
88. Gratiolet, L. P. (1867). Recherches sur l'anatomie de l'hippopotame. Victor Masson et fils, Paris.
89. Gray, J. E. (1821). On the natural arrangement of vertebrose animals. London Medical Repository 15, 296-310.
90. Grey, J. & Harper, D. M. (2002). Using stable isotope analyses to identify allochthonous inputs to lake Naivasha mediated via the hippopotamus gut. Isotopes in Environmental and Health Studies 38, 245-250.
91. Griffin, D. L. (2002). Aridity and humidity: two aspects of the late Miocene climate of North Africa and the Mediterranean. Palaeogeography, Palaeoclimatology, Palaeoecology 182, 68-91.
92. Harris, J. M. (1991). Family Hippopotamidae. In Koobi Fora Research Project, vol. 3 (ed. J. M. Harris), pp. 31-85. Clarendon Press, Oxford.
93. Harris, J. M., Cerling, T. E., Leakey, M. G. & Passey, B. H. (2008). Stable isotope ecology of fossil hippopotamids from the Lake Turkana Basin of East Africa. Journal of Zoology 275, 323-331.
94. Harris, J. M. & Liu, L. (2007). Superfamily Suoidea. In The evolution of artiodactyls (ed. D. R. Prothero and S. E. Foss), pp. 130-150. The Johns Hopkins University Press, Baltimore.
95. Harrison, T. (1997). The anatomy, paleobiology, and phylogenetic relationships of the Hippopotamidae (Mammalia, Artiodactyla) from the Manonga Valley, Tanzania. In Neogene Paleontology of the Manonga Valley, Tanzania. Topics in Geobiology (ed. T. Harrison), pp. 137-190. Plenum Press, New York.
96. Hermsen, E. J. & Hendricks, J. R. (2008). W(h)ither fossils? Studying morphological character evolution in the age of molecular sequences. Annals of the Missouri Botanical Garden 95, 72-100.
97. Hooijer, D. A. (1950). The fossil Hippopotamidae of Asia, with notes on the recent species. Zoologische Verhandelingen 8, 123.
98. Houtemaker, J. L. & Sondaar, P. Y. (1979). Osteology of the fore limb of the Pleistocene dwarf hippopotamus from Cyprus with special reference to phylogeny and function. Palaeontology B, 82, 411-448.
99. Hunt, G. & Roy, K. (2006). Climate change, body size evolution, and Cope's Rule in deep-sea ostracodes. Proceedings of the National Academy of Sciences of the United States of America 103, 1347-1352.
100. Inuzuka, N. (2000). Aquatic adaptations in desmostylians. Historical Biology 14, 97-113.
101. Jablonski, N. (2003). The hippo's tale: how the anatomy and physiology of late Neogene Hexaprotodon shed light on Late Neogene environmental change. Quaternary International 117, 119-123.
102. Janis, C. M. (1986). An estimation of tooth volume and hypsodonty indices in ungulate mammals, and the correlation of these factors with dietary preference. In Teeth Revisited, vol. 53. Sciences de la terre (ed. D. E. Russell, J. P. Santoro and D. Sigogneau-Russell), pp. 367-387, Paris.
103. Joyce, D. A., Lunt, D. H., Bills, R., Turner, G. F., Katongo, C., Duftner, N., Sturmbauer, C. & Seehausen, O. (2005). An extant cichlid fish radiation emerged in an extinct Pleistocene lake. Nature 435, 90-95.
104. Kingdon, J. (1979). Artiodactyls. Pigs. Hippopotamids. In East African mammals. An atlas of evolution in Africa, vol. III B (large mammals) (ed. J. Kingdon), pp. 180-277. Academic Press, London.
105. Kingston, J. D., Marino, B. D. & Hill, A. (1994). Isotopic evidence for Neogene hominid paleoenvironments in the Kenya Rift Valley. Science 264, 955-959.
106. Kivell, T. L. & Schmitt, D. (2009). Independent evolution of knuckle-walking in African apes shows that humans did not evolve from a knuckle-walking ancestor. Proceedings of the National Academy of Sciences of the United States of America 106, 14241-14246.
107. Krijgsman, W., Hilgen, F. J., Raffi, I., Sierro, F. J. & Wilson, D. S. (1999). Chronology, causes and progression of the Messinian salinity crisis. Nature 400, 652-655.
108. Kubitzki, K., Sengbusch, P. v. & Poppendieck, H. H. (1991). Parallelism, its evolutionary origin and systematic significance. Aliso 13, 191-206.
109. Kulemzina, A. I., Trifonov, V. A., Perelman, P. L., Rubtsova, N. V., Volobuev, V., Ferguson-Smith, M. A., Stanyon, R., Yang, F. & Graphodatsky, A. S. (2009). Cross-species chromosome painting in Cetartiodactyla: Reconstructing the karyotype evolution in key phylogenetic lineages. Chromosome Research 17, 419-436.
110. Langer, P. (2001). Evidence from the digestive tract on phylogenetic relationships in ungulates and whales. 39, 77-90.
111. Leakey, M. G. & Harris, J. M. (2003). Summary. In Lothagam. The dawn of humanity in Eastern Africa (ed. J. M. Harris and M. G. Leakey), pp. 609-648. Columbia University Press, New York.
112. Leidy, J. (1852). [Attribution of Hippopotamus liberiensis to a new genus]. Proceedings of the National Academy of Sciences, Philadelphia 6, 52.
113. Lewison, R. & Oliver, W. (2009a). Choeropsis liberiensis In IUCN Red List of Threatened Species (ed. IUCN 2009).
114. Lewison, R. & Oliver, W. (2009b). Hippopotamus amphibius In IUCN Red List of Threatened Species (ed. IUCN 2009).
115. Lihoreau, F. (2003). Systématique et paléoécologie des Anthracotheriidae [Artiodactyla; Suiformes] du Mio-Pliocène de l'Ancien Monde: implications paléobiogéographiques. Thèse NC thesis, Université de Poitiers.
116. Lihoreau, F., Barry, J., Blondel, C., Chaimanee, Y., Jaeger, J.-J. & Brunet, M. (2007). Anatomical revision of the genus Merycopotamus (Artiodactyla; Anthracotheriidae): its significance for late Miocene mammal dispersal in Asia. Palaeontology 50, 503-524.
117. Lihoreau, F., Boisserie, J.-R., Viriot, L., Coppens, Y., Likius, A., Mackaye, H. T., Tafforeau, P., Vignaud, P. & Brunet, M. (2006). Anthracothere dental anatomy reveals a late Miocene Chado-Libyan bioprovince. Proceedings of the National Academy of Sciences of the United States of America 103, 8763-8767.
118. Lihoreau, F. & Ducrocq, S. (2007). Family Anthracotheriidae. In The evolution of artiodactyls (ed. D. R. Prothero and S. E. Foss), pp. 89-105. The Johns Hopkins University Press, Baltimore.
119. Linné, C. v. (1758). Systema naturae per regna tria naturae, secundum classes, ordines, genera, species, cum characteribus, differentiis, synonymis, locis. Laurentii Salvii Holmiae, Stockolm.
120. Liu, A. G. S. C., Seiffert, E. R. & Simons, E. L. (2008). Stable isotope evidence for an amphibious phase in early proboscidean evolution. Proceedings of the National Academy of Sciences of the United States of America 105, 5786-5791.
121. Liu, L. (2003). Chinese fossil Suoidea. Systematics, evolution, and paleocology. Ph. D. dissertation NC thesis, University of Helsinki.
122. Lock, J. M. (1972). The effects of hippopotamus grazing on grasslands. Journal of Ecology 60, 445-467.
123. Lomolino, M. V. (2005). Body size evolution in insular vertebrates: generality of the island rule. Journal of Biogeography 32, 1683-1699.
124. Lomolino, M. V., Sax, D. F., Riddle, B. R. & Brown, J. H. (2006). The island rule and a research agenda for studying ecogeographical patterns. Journal of Biogeography 33, 1503-1510.
125. Louchart, A. (2008). Emergence of long distance bird migrations: a new model integrating global climate changes. Naturwissenschaften 95, 1109-1119.
126. Lovejoy, C. O. (2009). Reexamining human origins in light of Ardipithecus ramidus. Science 326, 74e1-74e8.
127. Luckett, W. P. & Hong, N. (1998). Phylogenetic relationships between the orders Artiodactyla and Cetacea: a combined assessment of morphological and molecular evidence. Journal of Mammalian Evolution 5, 127-182.
128. Lusseau, D. (2003). The emergence of cetaceans: phylogenetic analysis of male social behaviour supports the Cetartiodactyla clade. Journal of Evolutionary Biology 16, 531-535.
129. Lydekker, R. (1876). Notes on the osteology of Merycopotamus dissimilis. Records of the Geological Survey of India 9, 144-153.
130. MacFadden, B. J. (1998). Tales of two rhinos: isotopic ecology, paleodiet, and niche differenciation of Aphelops and Teleoceras from the Florida Neogene. Paleobiology 24, 274-286.
131. MacFadden, B. J. (2005). Diet and habitat of toxodont megaherbivores (Mammalia, Notoungulata) from the late Quaternary of South and Central America. Quaternary Research 65, 113-124.
132. Madar, S. I. (2007). The postcranial skeleton of early Eocene pakicetid cetaceans. Journal of Paleontology 81, 176-200.
133. Marcot, J. D. (2007). Molecular phylogeny of terrestrial artiodactyls: conflicts and resolution. In The evolution of artiodactyls (ed. D. R. Prothero and S. E. Foss), pp. 4-18. The Johns Hopkins University Press, Baltimore.
134. Marques, A. C. & Gnaspini, P. (2001). The problem of characters susceptible to parallel evolution in phylogenetic reconstructions: suggestion of a practical method and its application to cave animals. Cladistics 17, 371-381.
135. Martin, R. D., MacLarnon, A. M., Phillips, J. L., Dussubieux, L., Williams, P. R. & Dobyns, W. B. (2006). Comment on "The brain of LB1, Homo floresiensis". Science 312, 999b.
136. Maslin, M. M. & Christensen, B. (2007). Tectonics, orbital forcing, global climate change, and human evolution in Africa: introduction to the African paleoclimate special volume. Journal of Human Evolution 53, 443-464.
137. Matthew, W. D. (1929). Critical observations upon Siwalik mammals. Bulletin of the American Museum of Natural History 56, 437-560.
138. May-Collado, L. & Agnarsson, I. (2006). Cytochrome b and Bayesian inference of whale phylogeny. Molecular Phylogenetics and Evolution 38, 344-354.
139. Mayr, E. & O'Hara, R. J. (1986). The biogeographic evidence supporting the Pleistocene forest refuge hypothesis. Evolution 40, 55-67.
140. McCarthy, T. S., Ellery, W. N. & Bloem, A. (1998). Some observations on the geomorphological impact of hippopotamus (Hippopotamus amphibius L.) in the Okavango Delta, Botswana. African Journal of Ecology 36, 44-56.
141. McKee, J. K. (2001). Faunal turnover rates and mammalian biodiversity of the late Pliocene and Pleistocene of eastern Africa. Paleobiology 27, 500-511.
142. McNaughton, S. J., Tarrants, J. L., McNaughton, M. M. & Davis, R. H. (1985). Silica as a defense against herbivory and a growth promotor in African grasses. Ecology 66, 528-535.
143. Meehan, T. J. & Martin, L. D. (2003). Extinction and re-evolution of similar adaptive types (ecomorphs) in Cenozoic North American ungulates and carnivores reflect van der Hammen's cycles. Naturwissenschaften 90, 131-135.
144. Meisner, A. D., Klaus, A. V. & O'Leary, M. A. (2005). Sperm head morphology in 36 species of artiodactylans, perissodactylans, and cetaceans (Mammalia). Journal of Morphology 263, 179-202.
145. Merceron, G., Blondel, C., Brunet, M., Sen, S., Solounias, N., Viriot, L. & Heintz, E. (2004). The Late Miocene paleoenvironment of Afghanistan as inferred from dental microwear in artiodactyls. Palaeogeography, Palaeoclimatology, Palaeoecology 207, 143-163.
146. Meulenkamp, J. E. & Sissingh, W. (2003). Tertiary palaeogeography and tectonostratigraphic evolution of the Northern and Southern Peri-Tethys platforms and the intermediate domains of the African-Eurasian convergent plate boundary zone. Palaeogeography, Palaeoclimatology, Palaeoecology 196, 209-228.
147. Montgelard, C., Catzeflis, F. M. & Douzery, E. (1997a). Phylogenetic relationships of artiodactyls and cetaceans as deduced from the comparison of cytochrome b and 12s rRNA mitochondrial sequences. Molecular Biology and Evolution 14, 550-559.
148. Montgelard, C., Ducrocq, S. & Douzery, E. (1997b). What is a suiforme (Artiodactyla)? contribution of cranioskeletal and mitochondrial DNA data. Molecular Phylogenetics and Evolution 9, 528-532.
149. Moore, J. W. (2006). Animal ecosystem engineers in streams. Bioscience 56, 237-246.
150. 4 plants in the Neogene from Pakistan and Kenya Nature 367, 162-165.
151. Morton, S. G. (1849). Additional information on a new living species of Hippopotamus. Journal of the Academy of Natural Sciences of Philadelphia 2, 231-239.
152. Muizon, C. D. & McDonald, H. G. (1995). An aquatic sloth from the Pliocene of Peru. Nature 375, 224-227.
153. Naylor, G. J. P. & Adams, D. C. (2001). Are the fossil data really at odds with the molecular data? Morphological evidence for Cetartiodactyla phylogeny reexamined. Systematic Biology 50, 444-453.
154. Naylor, G. J. P. & Adams, D. C. (2003). Total evidence versus relevant evidence: a response to O'Leary et al. (2003). Systematic Biology 52, 865-868.
155. Nikaido, M., Rooney, A. P. & Okada, N. (1999). Phylogenetic relationships among cetartiodactyls based on insertions of short and long interpersed elements: hippopotamuses are the closest extant relatives of whales. Proceedings of the National Academy of Sciences of the United States of America 96, 10261-10266.
156. Nomura, O. & Yasue, H. (1999). Genetic relationships among hippopotamus, whales, and bovine based on SINE insertion analysis. Mammalian Genome 10, 526-527.
157. O'Brien, E. M. & Peters, C. R. (1999). Landforms, climate, ecogeographic mosaics, and the potential for hominine diversity in Pliocene Africa. In African biogeography, climate change and Human evolution (ed. T. G. Bromage and F. Schrenk), pp. 115-137. Oxford University Press, Oxford.
158. Okello, J. B. A., Nyakaana, S., Masembe, C., Siegismund, H. R. & Arctander, P. (2005). Mitochondrial DNA variation of the common hippopotamus: evidence for a recent population expansion. Heredity 95, 206-215.
159. O'Leary, M., Gatesy, J. & Novacek, M. J. (2003). Are the dental data really at odds with the molecular data?Morphological evidence for whale phylogeny (re)reexamined. Systematic Biology 52, 853-864.
160. O'Leary, M. A. (1999). Parsimony analysis of total evidence from extinct and extant taxa and the cetacean-artiodactyl question (Mammalia, Ungulata). Cladistics 15, 315-330.
161. O'Leary, M. A. (2001). The phylogenetic position of cetaceans: further combined data analyses, comparisons with the stratigraphic record and a discussion of character optimization. American Zoologist 41, 487-506.
162. O'Leary, M. A. (2009). "Artiodactylans": phylogeny and the fossil record. Journal of Mammalian Evolution 16, 65-67.
163. O'Leary, M. A. & Gatesy, J. (2008). Impact of increased character sampling on the phylogeny of Cetartiodactyla (Mammalia): combined analysis including fossils. Cladistics 24, 397-442.
164. O'Leary, M. A. & Geisler, J. H. (1999). The position of Cetacea within Mammalia: phylogenetic analysis of morphological data from extinct and extant taxa. Systematic Biology 48, 455-490.
165. Olivier, R. C. D. (1975). Aspects of skin physiology in the pygmy hippopotamus Choeropsis liberiensis. Journal of Zoology 176, 211-213.
166. Orliac, M., Antoine, P.-O. & Duranthon, F. (2006). The Suoidea (Mammalia, Artiodactyla), exclusive of Listriodontinae, from the early Miocene of Béon 1 (Montréal-du-Gers, SW France, MN4). Geodiversitas 28, 685-718.
167. Orliac, M., Boisserie, J.-R., Lihoreau, F. & MacLatchy, L. (2010). Early Miocene hippopotamids (Cetartiodactyla) constrain the phylogenetic and spatiotemporal settings of hippopotamid origin. Proceedings of the National Academy of Sciences of the United States of America 107, 11871-11876.
168. Otero, O., Pinton, A., Mackaye, H. T., Likius, A., Vignaud, P. & Brunet, M. (2009). Fishes and palaeogeography of the African drainage basins: relationships between Chad and neighbouring basins throughout the Mio-Pliocene. Palaeogeography, Palaeoclimatology, Palaeoecology 274, 134-139.
169. Pearson, H. S. (1927). On the skulls of early Tertiary Suidae, together with an account of the otic region in some other primitive Artiodactyla. Philosophical Transactions of the Royal Society of London 215, 389-460.
170. Pickford, M. (1983). On the origins of Hippopotamidae together with descriptions of two species, a new genus and a new subfamily from the Miocene of Kenya. Géobios 16, 193-217.
171. Pickford, M. (1989). Update on hippo origins. Comptes Rendus de l'Académie des Sciences 309, 163-168.
172. Pickford, M. (1991). Revision of the Neogene Anthracotheriidae of Africa. The Geology of Libya 4, 1491-1525.
173. Pickford, M. (1993). Old World suoid systematics, phylogeny, biogeography and biostratigraphy. Paleontologia i Evolució 26-27, 237-269.
174. Pickford, M. (1997). Lower Miocene suiformes from the northern Sperrgebiet, Namibia, including new evidences for the systematic position of the Sanitheriidae. Comptes Rendus de l'Académie des Sciences 325, 285-292.
175. Pickford, M. (2007a). A new suiform (Artiodactyla, Mammalia) from the Early Miocene of East Africa. Comptes Rendus Palevol 6, 221-229.
176. Pickford, M. (2007b). Suidae and Hippopotamidae from the middle Miocene of Kipsaraman, Kenya and other sites in East Africa. Paleontological Research 11, 85-105.
177. Pickford, M. (2008). The myth of the hippo-like anthracothere: the eternal problem of homology and convergence. Revista Española de Paleontología 23, 31-90.
178. Pickford, M. & Morales, J. (2003). New Listriodontinae (Mammalia, Suidae) from Europe and a review of listriodont evolution, biostratigraphy and biogeography. Geodiversitas 25, 347-404.
179. Pickford, M. & Tsujikawa, H. (2005). A partial cranium of Diamantohyus nadirus from the Aka Aiteputh Formation (16-15 Ma), Kenya. Paleontological Research 9, 319-328.
180. Price, S. A., Bininda-Emonds, O. R. P. & Gittleman, J. L. (2005). A complete phylogeny of the whales, dolphins and even-toed hoofed mammals (Cetartiodactyla). Biological Reviews 80, 445-473.
181. Prothero, D. R. (2004). Did impacts, volcanic eruptions, or climate change affect mammalian evolution? Palaeogeography, Palaeoclimatology, Palaeoecology 214, 283-294.
182. Reyment, R. A. (1983). Palaeontological aspects of island biogeography: colonization and evolution of mammals on Mediterranean islands. Oikos 41, 299-306.
183. Robinson, P. T. (in press). Choeropsis liberiensis (Morton). In The Mammals of Africa, vol. Vol. 6. Pigs, Deer, Giraffe, Bovids, and Hippos., pp. 244-254. Academic Press, Amsterdam.
184. Sanchez-Villagra, M. R., Aguilera, O. & Horovitz, I. (2003). The anatomy of the world's largest extinct rodent. Science 301, 1708-1710.
185. Sanson, G. D., Kerr, S. A. & Gross, K. A. (2007). Do silica phytoliths really wear mammalian teeth? Journal of Archaeological Science 34, 526-531.
186. Scholz, C. A., Johnson, T. C., Cohen, A. S., King, J. W., Peck, J. A., Overpeck, J. T., Talbot, M. R., Brown, E. T., Kalindekafe, L., Amoako, P. Y. O., Lyons, R. P., Shanahan, T. M., Castañeda, I. S., Heil, C. W., Forman, S. L., McHargue, L. R., Beuning, K. R., Gomez, J. & Pierson, J. (2007). East African megadroughts between 135 and 75 thousand years ago and bearing on early-modern human origins. Proceedings of the National Academy of Sciences of the United States of America 104, 16416-16421.
187. 4 grass expansion across sub-Saharan Africa. Journal of Human Evolution 53, 549-559.
188. Senut, B., Pickford, M. & Ségalen, L. (2009). Neogene desertification of Africa. Comptes Rendus Geoscience 341, 591-602.
189. Sepulchre, P., Ramstein, G., Fluteau, F., Schuster, M., Tiercelin, J. J. & Brunet, M. (2006). Tectonic uplift and eastern Africa aridification. Science 313, 1419-1423.
190. Shapiro, M. D., Bell, M. A. & Kingsley, D. M. (2006). Parallel genetic origins of pelvic reduction in vertebrates. Proceedings of the National Academy of Sciences of the United States of America 103, 13753-13758.
191. Shubin, N., Tabin, C. & Carroll, S. (2009). Deep homology and the origins of evolutionary novelty. Nature 457, 818-823.
192. Solounias, N. & Semprebon, G. (2002). Advances in the reconstruction of ungulate ecomorphology with the application to early fossil equids. American Museum Novitates 3366, 1-49.
193. Sondaar, P. Y. (1977). Insularity and its effect on mammal evolution. In Major patterns in Vertebrate evolution (ed. M. K. Hecht, P. C. Goody and B. M. Hecht), pp. 671-707. Plenum publishing corporation, New York.
194. Spaulding, M., O'Leary, M. A. & Gatesy, J. (2009). Relationships of Cetacea (Artiodactyla) among mammals: increased taxon sampling alters interpretations of key fossils and character evolution. Plos One 4, 1-10.
195. Spoor, F., Leakey, M. G., Gathogo, P. N., Brown, F. H., Antón, S. C., McDougall, I., Kiarie, C., Manthi, F. K. & Leakey, L. N. (2007). Implications of new early Homo fossils from Ileret, east of Lake Turkana, Kenya. Nature 448, 688-691.
196. Springer, M. S., Stanhope, M. J., Madsen, O. & de Jong, W. W. (2004). Molecules consolidate the placental mammal tree. Trends in Ecology and Evolution 19, 430-438.
197. Springer, M. S., Teeling, E. C., Madsen, O., Stanhope, M. J. & de Jong, W. W. (2001). Integrated fossil and molecular data reconstruct bat echolocation. Proceedings of the National Academy of Sciences of the United States of America 98, 6241-6246.
198. Steensma, K. J. & Hussain, S. T. (1992). Merycopotamus dissimilis (Artiodactyla, Mammalia) from the Upper Siwalik Subgroup and its affinities with Asian and African forms. Proceedings of the Koninklijke Nederlandse Akademie van Wetenschappen 95, 97-108.
199. Stewart, K. M. (2001). The freshwater fish of Neogene Africa (Miocene-Pleistocene): systematics and biogeography. Fish and Fisheries 2, 177-230.
200. Stuenes, S. (1989). Taxonomy, habits, and relationships of the subfossil Madagascan hippopotami Hippopotamus lemerlei and H. madagascariensis. Journal of Vertebrate Paleontology 9, 241-268.
201. Su, D. & Harrison, T. (2007). The paleoecology of the Upper Laetolil Beds at Laetoli: a reconsideration of the large mammal evidence. In Hominin Environments in the East African Pliocene (ed. R. Bobe, Z. Alemseged and A. K. Behrensmeyer), pp. 279-313. Springer, Dordrecht.
202. Sudre, J. (1978). Les artiodactyles de l'Eocène moyen et supérieur d'Europe occidentale; systématique et évolution. Mémoires et Travaux de l'Institut de Montpellier de l'Ecole Pratique des Hautes Etudes 7, 1-229.
203. Theodor, J. M. (2004). Molecular clock divergence estimates and the fossil record of Cetartiodactyla. Journal of Paleontology 78, 39-44.
204. Theodor, J. M. & Foss, S. E. (2005). Deciduous dentitions of Eocene cebochoerid artiodactyls and cetartiodactyl relationships. Journal of Mammalian Evolution 12, 161-181.
205. Thewissen, J. G. M., Cooper, L. N., Clementz, M. T., Bajpai, S. & Tiwari, B. N. (2007). Whales originated from aquatic artiodactyls in the Eocene epoch of India. Nature 450, 1190-1195.
206. Thewissen, J. G. M., Cooper, L. N., Clementz, M. T., Bajpai, S. & Tiwari, B. N. (2009). Thewissen et al. reply. Nature 458, E5.
207. Thewissen, J. G. M., Madar, S. I. & Hussain, S. T. (1996). Ambulocetus natans, an Eocene cetacean (Mammalia) from Pakistan. Courier Forschungs Institut Senckenberg 191, 1-86.
208. Thewissen, J. G. M. & Williams, E. M. (2002). The early radiations of Cetacea (Mammalia): evolutionary pattern and developmental correlations. Annual Review of Ecology and Systematics 33, 73-90.
209. Thewissen, J. G. M., Williams, E. M., Roe, L. J. & Hussain, S. T. (2001). Skeletons of terrestrial cetaceans and the relationship of whales to artiodactyls. Nature 413, 277-281.
210. Trauth, M. H., Maslin, M. A., Deino, A. L., Strecker, M. R., Bergner, A. G. N. & Dühnforth, M. (2007). High- and low-latitude forcing of Plio-Pleistocene East African climate and human evolution. Journal of Human Evolution 53, 475-486.
211. Uhen, M. D. (2007). Evolution of marine mammals: back to the sea after 300 Million Years. The Anatomical Record 290, 514-522.
212. Ursing, B. M. & Arnason, U. (1998). Analyses of mitochondrial genomes strongly support a hippopotamus-whale clade. Proceedings of the Royal Society of London B 265, 2251-2255.
213. van Tuinen, M. & Hadly, E. A. (2004). Calibration and error in placental molecular clocks: a conservative approach using the cetartiodactyl fossil record. Journal of Heredity 95, 200-208.
214. Verheyen, R. (1954). Monographie éthologique de l'hippopotame (Hippopotamus amphibius Linné). Institut des Parcs nationaux du Congo belge, Morges.
215. Verweij, R. J. T., Verrelst, J., Loth, P. E., Heitkönig, I. M. A. & Brunsting, A. M. H. (2006). Grazing lawns contribute to the subsistence of mesoherbivores on dystrophic savannas. Oikos 114, 108-116.
216. Vignaud, P., Duringer, P., Mackaye, H. T., Likius, A., Blondel, C., Boisserie, J.-R., Bonis, L. d., Eisenmann, V., Etienne, M. E., Geraads, D., Guy, F., Lehmann, T., Lihoreau, F., Lopez-Martínez, N., Mourer-Chauviré, C., Otero, O., Rage, J.-C., Schuster, M., Viriot, L., Zazzo, A. & Brunet, M. (2002). Geology and palaeontology of the upper Miocene Toros-Ménalla hominid locality, Chad. Nature 418, 152-155.
217. Waddell, P. J., Okada, N. & Hasegawa, M. (1999). Towards resolving the interordinal relationships of placental mammals. Systematic Biology 48, 1-5.
218. Wall, W. P. (1983). The correlation between high limb-bone density and aquatic habits in recent mammals. Journal of Paleontology 57, 197-207.
219. Wall, W. P. & Heinbaugh, K. L. (1999). Locomotor adaptations in Metamynodon planifrons compared to other amynodontids (Perissodactyla, Rhinocerotoidea). National Park Service Paleontological Research 4, 8-17.
220. Weston, E. M. (2000). A new species of hippopotamus Hexaprotodon lothagamensis (Mammalia: Hippopotamidae) from the late Miocene of Kenya. Journal of Vertebrate Paleontology 20, 177-185.
221. Weston, E. M. (2003a). Evolution of ontogeny in the hippopotamus skull: using allometry to dissect developmental change. Biological Journal of the Linnean Society 80, 625-638.
222. Weston, E. M. (2003b). Fossil Hippopotamidae from Lothagam. In Lothagam. The dawn of humanity in eastern Africa (ed. J. M. Harris and M. G. Leakey), pp. 380-410. Columbia University Press, New York.
223. Weston, E. M. & Boisserie, J.-R. (2010). Chapter 17. Hippopotamidae. In Cenozoic Mammals of Africa (ed. L. Werdelin and W. Sanders), pp. 853-871. University of California Press.
224. Weston, E. M. & Lister, A. M. (2009). Insular dwarfism in hippos and a model for brain size reduction in Homo floresiensis. Nature 459, 85-88.
225. Weston, E. M., Madden, R. H. & Sánchez-Villagra, M. R. (2004). Early Miocene asthrapotheres (Mammalia) from northern South America. Special Papers in Paleontology 71, 81-97.
226. White, T. D. (1995). African omnivores: global climatic change and Plio-Pleistocene hominids and suids. In Paleoclimate and evolution with emphasis on Human origins (ed. E. S. Vrba, G. H. Denton, T. C. Partridge and L. H. Burckle), pp. 369-384. Yale University Press, New Haven.
227. White, T. D., Asfaw, B., Beyene, Y., Haile-Selassie, Y., Lovejoy, C. O., Suwa, G. & WoldeGabriel, G. (2009). Ardipithecus ramidus and the paleobiology of early hominids. Science 326, 75-86.
228. Wolanski, E. & Gereta, E. (1999). Oxygen cycle in a hippo pool, Serengeti National Park, Tanzania. African Journal of Ecology 37, 419-423.
229. Wolanski, E. & Gereta, E. (2001). Water quantity and quality as the factors driving the Serengeti ecosystem, Tanzania. Hydrobiologia 458, 169-180.
230. Wolfenden, E., Ebinger, C., Yirgu, G., Deino, A. & Ayalew, D. (2004). Evolution of the northern Main Ethiopian rift: birth of a triple junction. Earth and Planetary Science Letters 224, 213-228.
231. Woodburne, M. O., Gunnell, G. F. & Stucky, R. K. (2009). Climate directly influences Eocene mammal faunal dynamics in North America. Proceedings of the National Academy of Sciences of the United States of America 106, 13399-13403.
232. Wright, D. E. (1998). Tayassuidae. In Evolution of Tertiary mammals of North America. Volume1: terrestrial carnivores, ungulates and ungulatelike mammals (ed. C. M. Janis, K. M. Scott and L. L. Jacobs), pp. 389-401. Cambridge University Press, Cambridge.
233. Zachos, J., Pagani, M., Sloan, L., Thomas, E. & Billups, K. (2001). Trends, rhythms, and aberrations in global climate 65 Ma to present. Science 292, 686-693.