Baker, M. L., Wares, J. P., Harrison, G. A., and Miller, R. D. (2004). Relationships among the families and orders of marsupials and the major mammalian lineages based on recombination activating gene-1. Journal of Mammalian Evolution, 11, 1–16.CrossRefGoogle Scholar

Belov, K., Hellman, L., and Cooper, D. W. (2002). Characterization of echidna IgM provides insights into the divergence of extant mammals. Developmental and Comparative Immunology, 26, 831–9.CrossRefGoogle Scholar

Butler, P. M. and Hooker, J. J. (2005). New teeth of allotherian mammals from the English Bathonian, including the earliest multituberculates. Acta Palaeontologica Polonica, 50, 185–207.Google Scholar

Case, J. A. and Woodburne, M. O. (1986). South American marsupials: a successful crossing of the Cretaceous–Tertiary boundary. Palaios, 1, 413–16.CrossRefGoogle Scholar

Case, J. A., Goin, F. J., and Woodburne, M. O. (2005). “South American” marsupials from the Late Cretaceous of North America, and the origin of marsupial cohorts. Journal of Mammalian Evolution, 12, 461–94.CrossRefGoogle Scholar

Cifelli, R. L. (1993). Theria of metatherian–eutherian grade and the origin of marsupials. In Mammal Phylogeny: Mesozoic Differentiation, Multituberculates, Monotremes, Early Therians and Marsupials, ed. Szalay, F. S., Novacek, M. J., and McKenna, M. C., pp. 205–15. New York: Springer-Verlag.Google Scholar

(1999). Tribosphenic mammal from the North American early Cretaceous. Nature, 401, 363–6.CrossRef

Cifelli, R. L. and Muizon, C. (1997). Dentition and jaw of Kokopellia juddi, a primitive marsupial or near-marsupial from the medial Cretaceous of Utah. Journal of Mammalian Evolution, 4, 241–58.CrossRefGoogle Scholar

Cope, E. D. (1884). Second addition to the knowledge of the Puerco fauna. Proceedings of the American Philosophical Society, 21, 309–24.Google Scholar

Crochet, J.-Y. (1979). Les Marsupiaux du Tertiare d'Europe. Paris: Éditions de la Foundation Singer-Polignac.Google Scholar

Eizirik, E., Murphy, W. J., and O'Brien, S. J. (2001). Molecular dating and biogeography of the early placental mammal radiation. Journal of Heredity, 92, 212–19.CrossRefGoogle ScholarPubMed

Gilbert, N. and Labuda, D. (2000). Evolutionary inventions and continuity of CORE-SINES in mammals. Journal of Molecular Biology, 298, 365–77.CrossRefGoogle ScholarPubMed

Gill, T. (1872). Arrangement of the families of mammals with analytical tables. Smithsonian Miscellaneous Collections, 11, 1–98.Google Scholar

Goin, F. J. (2003). Early marsupial radiations in South America. In Predators with Pouches: The Biology of Carnivorous Marsupials, ed. Jones, M., Dickman, C., and Archer, M., pp. 30--42. Collingwood, Australia: CSIRO.Google Scholar

Gregory, W. K. (1947). The monotremes and the palimpsest theory. Bulletin of the American Museum of Natural History, 88, 1–52.Google Scholar

Haeckel, E. (1898). Ueber unsere gegenwärtige Kenntniss vom Ursprung des Menschen. Bonn: Vortrag gehalten auf dem 4en Internationalen Zoologen-Congress, Cambridge.

Hedges, S. B., Parker, P., Sibley, G., and Kumar, S. (1996). Continental breakup and ordinal diversification of birds and mammals. Nature, 381, 226–8.CrossRefGoogle ScholarPubMed

Hunter, J. P. and Janis, C. M. (2006). Spiny Norman in the “Garden of Eden”? Ausktribosphenos and the geography of placental mammalian origins. Journal of Mammalian Evolution, 8, 107–24.Google Scholar

Hurum, J. H., Luo, Z.-X., and Kielan-Jaworowska, Z. (2006). Were mammals originally venomous?Acta Palaeontologica Polonica, 51, 1–11.Google Scholar

Huxley, T. H. (1880). On the application of the laws of evolution to the arrangement of Vertebrata, and more particularly of the Mammalia. Proceedings of the Zoological Society of London, 1880, 649– 62.Google Scholar

Janke, A., Xu, X., and Arnason, U. (1997). The complete mitochondrial genome of the wallaroo (Macropus robustus) and the phylogenetic relationship among Monotremata, Marsupialia and Eutheria. Proceedings of the National Academy of Sciences, USA, 94, 1276–81.CrossRefGoogle ScholarPubMed

Janke, A., Magnell, O., Wieczorek, G., Westerman, M., and Arnason, U. (2002). Phylogenetic analysis of 18S RNA and the mitochondrial genomes of the wombat, Vombatus ursinus, and the spiny anteater, Tachyglossus aculeatus: increased support for the Marsupionta hypothesis. Journal of Molecular Evolution, 54, 71– 80.CrossRefGoogle ScholarPubMed

Jenkins, F. A., Gatesy, S. M., Shubin, N. H., and Amaral, W. W. (1997). Haramiyids and Triassic mammalian evolution. Nature, 385, 715–18.CrossRefGoogle ScholarPubMed

Ji, Q., Luo, Z.-X., Yuan, C.-X., et al. (2002). The earliest known eutherian mammal. Nature, 416, 816–22.CrossRefGoogle ScholarPubMed

Kielan-Jaworowska, Z. (1971). Skull structure and affinities of the Multituberculata. Acta Paleontologia Polonica, 25, 5–41.Google Scholar

Kielan-Jaworowska, Z., Cifelli, R. L., and Luo, Z.-X. (2004). Mammals from the Age of Dinosaurs: Origins, Evolution, and Structure. New York: Columbia University Press.CrossRefGoogle Scholar

Killian, J. K., Buckley, T. R., Stewart, N., Munday, B. L., and Jirtle, R. L. (2001). Marsupials and eutherians reunited: genetic evidence for the Theria hypothesis of mammalian evolution. Mammalian Genome, 12, 513–17.CrossRefGoogle ScholarPubMed

Kirsch, J. A. W. (1977). The six percent solution: second thoughts about the adaptiveness of marsupials. American Scientist, 65, 276–88.Google Scholar

Kirsch, J. A. W. and Mayer, G. C. (1998). The platypus is not a rodent: DNA hybridization, amniote phylogeny and the palimpsest theory. Philosophical Transactions of the Royal Society London, B, 353, 1221–37.CrossRefGoogle Scholar

Kirsch, J. A. W., Dickerman, A. A., Reig, O. A., and Springer, M. S. (1991). DNA hybridization evidence for the Australasian affinity of Dromiciops australis. Proceedings of the National Academy of Sciences, USA, 88, 10465–9.CrossRefGoogle ScholarPubMed

Kirsch, J. A. W., Lapointe, F.-J., and Springer, M. S. (1997). DNA-hybridisation studies of marsupials and their implications for metatherian classification. Australian Journal of Zoology, 45, 211–80.CrossRefGoogle Scholar

Kitazoe,, Y., Hirohisa,, H., Waddell,, P. J., et al. (2007). Robust time estimate reconciles views of the antiquity of placental mammals. PLoS Online, 2, e384. doi: 10.1371/journal.pone.0000384.

Krause, D. W. (1982). Jaw movement, dental function, and diet in the Paleocene multituberculate Ptilodus. Paleobiology, 8, 265–81.CrossRefGoogle Scholar

Krause, D. W., Rogers, R. R., Forster, C. A., et al. (1999). The Late Cretaceous vertebrate fauna of Madagascar: implications for Gondwanan paleobiogeography. GSA Today, 9, 1–7.Google Scholar

Kullander, K., Carlson, B., and Hallbrook, F. (1997). Molecular phylogeny and evolution of the neurotropins from monotremes and marsupials. Journal of Molecular Evolution, 45, 311–21.CrossRefGoogle Scholar

Kumar, S. and Hedges, S. B. (1998). A molecular timescale for vertebrate evolution. Nature, 392, 917–20.CrossRefGoogle ScholarPubMed

Lee, M.-H., Schroff, R., Cooper, S. J. B., and Hope, R. (1999). Evolution and molecular characterization of a β-globin gene from the Australian echidna Tachyglossus aculeatus (Monotremata). Molecular Phylogenetics and Evolution, 12, 205–14.CrossRefGoogle Scholar

Lillegraven, J. A. (1975). Biological considerations of the marsupial–placental dichotomy. Evolution, 29, 707–22.CrossRefGoogle ScholarPubMed

(1984). Why was there a “marsupial-placental dichotomy.” [In Mammals: Notes for a Short Course, ed. P. D. Gingerich and C. Badgley.] University of Tennessee, Studies in Geology, 8, 72--86.

Luo, Z.-X., Cifelli, R. L., and Kielan-Jaworowska, Z. (2001). Dual origin of tribosphenic mammals. Nature, 409, 53–7.CrossRefGoogle ScholarPubMed

Luo, Z.-X., Kielan-Jaworowska, Z., and Cifelli, R. L. (2002). In quest for a phylogeny of Mesozoic mammals. Acta Paleontologica Polonica, 47, 1–78.Google Scholar

Luo, Z.-X., Ji, Q., Wible, J. R., and Yuan, C.-X. (2003). An Early Cretaceous tribosphenic mammal and metatherian evolution. Science, 302, 1934–40.CrossRefGoogle ScholarPubMed

Maddison, W. P. (1993). Missing data versus missing characters in phylogenetic analysis. Systematic Biology, 42, 576–81.CrossRefGoogle Scholar

Madsen, O., Scally, M., Douady, C. J., et al. (2001). Parallel adaptive radiations in two major clades of placental mammals. Nature, 409, 610–14.CrossRefGoogle ScholarPubMed

Marsh, O. C. (1880). Notice of Jurassic mammals representing two new orders. American Journal of Science, Series 3, 20, 235–9.CrossRefGoogle Scholar

Marshall,, L. G., Case,, J. A., and Woodburne,, M. O. (1990). Phylogenetic relationships of the families of marsupials. In Current Mammalogy, Vol. 2, ed. Genoways, H., pp. 33–405. New York: Plenum Press.Google Scholar

McKenna, M. C. and Bell, S. K. (1997). Classification of Mammals Above the Species Level. New York: Columbia University Press.Google Scholar

Meng, J. and Wyss, A. R. (1995). Monotreme affinities and low-frequency hearing suggested by multituberculate ear. Nature, 377, 141–4.CrossRefGoogle Scholar

Messer, M., Weiss, A. S., Shaw, D. C., and Westerman, M. (1998). Evolution of the monotremes: phylogenetic relationship to marsupials and eutherians, and estimation of divergence time based on α-lactalbumin amino acid sequences. Journal of Mammalian Evolution, 5, 95–105.CrossRefGoogle Scholar

Miao,, D. (1993). Cranial morphology and multituberculate relationships. In Mammal Phylogeny: Mesozoic Differentiation, Multituberculates, Monotremes, Early Therians and Marsupials, ed. Szalay, F. S., Novacek, M. J., and McKenna, M. C., pp. 63–74. New York: Springer-Verlag.Google Scholar

Murphy, W. J., Eizirik, E., Johnson, W. E., et al. (2001a). Molecular phylogenetics and the origins of placental mammals. Nature, 409, 614–18.CrossRefGoogle Scholar

Murphy, W. J., Eizirik, E., O'Brien, S. J., et al. (2001b). Resolution of the early placental mammal radiation using Bayesian phylogenetics. Science, 294, 2348–51.CrossRefGoogle Scholar

Novacek, M. J., Rougier, G. W., Wible, J. R., et al. (1997). Epipubic bones in eutherian mammals from the Late Cretaceous of Mongolia. Nature, 389, 483–6.CrossRefGoogle ScholarPubMed

Nowak, R. M., and Paradiso, J. L. (1983). Walker's Mammals of the World. Baltimore, MD: Johns Hopkins University Press.Google Scholar

Parker, T. J. and Haswell, W. A. (1897). A Text-book of Zoology. London: Macmillan.CrossRefGoogle Scholar

Penny, D. and Hasegawa, M. (1997). The platypus put in its place. Nature, 387, 549–50.CrossRefGoogle ScholarPubMed

Renfree,, M. R. (1993). Ontogeny, genetic control, and phylogeny of female reproduction in monotreme and marsupial mammals. In Mammal Phylogeny: Mesozoic Differentiation, Multituberculates, Monotremes, Early Therians and Marsupials, ed. Szalay, F. S., Novacek, M. J., and McKenna, M. C., pp. 4–20. New York: Springer-Verlag.Google Scholar

Retief, J. D., Winkfein, R. J., and Dixon, G. H. (1993). Evolution of the monotremes: the sequences of the protamine P1 genes in the platypus and echidna. European Journal of Biochemistry, 218, 457–61.CrossRefGoogle ScholarPubMed

Rich, T. H., Vickers-Rich, P., Constantine, A., et al. (1997). A tribosphenic mammal from the Mesozoic of Australia. Science, 278, 1438–42.CrossRefGoogle Scholar

Rich, T. H., Flannery, T. F., Trusler, P., et al. (2002). Evidence that monotremes and ausktribosphenids are not sister groups. Journal of Vertebrate Paleontology, 22, 466–9.CrossRefGoogle Scholar

Rich, T. H., Hopson, J. A., Musser, A. M., Flannery, T. F., and Vickers-Rich, P. (2005). Independent origins of middle ear bones in monotremes and therians. Science, 307, 910–14.CrossRefGoogle ScholarPubMed

Ride, W. D. L. (1964). A review of Australian fossil marsupials. Journal of the Proceedings of the Royal Society of Western Australia, 46, 97–131.Google Scholar

Ride, W. D. L. (1970). A Guide to the Native Mammals of Australia. Oxford: Oxford University Press.Google Scholar

Rougier, G. W., Wible, J. R., and Novacek, M. J. (1996). Multituberculate phylogeny. Nature, 379, 406–67.CrossRefGoogle Scholar

Rowe, T. (1988). Definition, diagnosis, and origin of Mammalia. Journal of Vertebrate Paleontology, 8, 241–64.CrossRefGoogle Scholar

Sánchez-Villagra, M. R., and Maier, W. (2003). Ontogenesis of the scapula in marsupial mammals, with special emphasis on perinatal stages of Didelphis and remarks on the origin of the therian scapula. Journal of Morphology, 258, 115–29.CrossRefGoogle Scholar

Sears, K. E. (2004). Constraints on the morphological evolution of marsupial shoulder girdles. Evolution, 58, 2535–70.Google ScholarPubMed

Sigogneau-Russell, D. (1991). First evidence of Multituberculata (Mammalia) in the Mesozoic of Africa. Neues Jahrbuch fur Palaontologie, Monatshefte, 1991, 119–25.Google Scholar

Simpson, G. G. (1945). The principles of classification and a classification of mammals. Bulletin of the American Museum of Natural History, 85, 1–350.Google Scholar

Smith, K. K. (1997). Comparative patterns of craniofacial development in eutherian and metatherian mammals. Evolution, 51, 1663–78.CrossRefGoogle ScholarPubMed

Smith, K. K. (2001). The evolution of mammalian development. Bulletin of the Museum of Comparative Zoology, 156, 119–35.Google Scholar

Springer, M. S., Westerman, M., Kavanagh, J. R., et al. (1998). The origin of the Australasian marsupial fauna and the phylogenetic affinities of the enigmatic Monito de Monte and the marsupial mole. Proceedings of the Royal Society of London, B, 265, 2381–6.CrossRefGoogle Scholar

Springer, M. S., DeBry, R. W., Douady, G., et al. (2001). Mitochondrial versus nuclear gene sequences in deep-level mammalian phylogeny reconstruction. Molecular Biology and Evolution, 18, 132–43.CrossRefGoogle ScholarPubMed

Szalay, F. S. (1994). Evolutionary History of the Marsupials and an Analysis of Osteological Characters. Cambridge, UK: Cambridge University Press.Google Scholar

Szalay, F. S. and Sargis, E. J. (2001). Model-based analysis of postcranial osteology of marsupials from the Palaeocene of Itaboraí (Brazil) and the phylogenetics and biogeography of the Metatheria. Geodiversitas, 23, 139–302.Google Scholar

Wible, J. R. (1991). Origin of Mammalia: the craniodental evidence re-examined. Journal of Vertebrate Paleontology, 11, 1–18.CrossRefGoogle Scholar

Wible,, J. R. and Hopson,, J. A. (1993). Basicranial evidence for early mammal phylogeny. In Mammal Phylogeny: Mesozoic Differentiation, Multituberculates, Monotremes, Early Therians, and Marsupials, ed. Szalay, F. S., Novacek, M. J., and McKenna, M. C., pp. 45–62. New York: Springer-Verlag.Google Scholar

Wible,, J. R., Rougier,, G. W., Novacek,, U. J., and Asher,, R. J. (2007). Cretaceous eutherians and Laurasian origin for placental mammals near the K/T boundary. Nature, 447, 1003–6.CrossRefGoogle Scholar

Woodburne, M. O. (2003). Monotremes as pretribosphenic mammals. Journal of Mammalian Evolution, 10, 195–248.CrossRefGoogle Scholar

Woodburne, M. O., Rich, T. H., and Springer, M. S. (2003). The evolution of tribospheny and the antiquity of mammalian clades. Molecular Phylogeny and Evolution, 28, 360–85.CrossRefGoogle ScholarPubMed

Zeller, U. (1999). Phylogeny and systematic relations of the Monotremata: why we need an integrative approach. Courier Forschungsinstitut Senckenberg, 215, 227–32.Google Scholar