Journal of Mammalian Evolution

, Volume 13, Issue 3–4, pp 171–210 | Cite as

Cretaceous Therian Tarsals and the Metatherian-Eutherian Dichotomy

Original Paper


Diverse metatherian and eutherian tarsal remains from the Late Cretaceous (middle-late Turonian) Bissekty Formation, Kyzylkum Desert, Uzbekistan (ca 90 MYA) are described. Their functional and taxonomic properties, along with those of other tarsal evidence, led to a reassessment of polarity hypotheses of therian, metatherian, and eutherian cruropedal attributes, and the consequences of this for phylogeny of taxa. There are calcaneal remains of several types of marsupials, and a single astragalus that probably belongs to one of these. This represents greater taxonomic diversity than the dental record suggests. Exceptionally large and distally extending peroneal processes, and small and steeply angled calcaneocuboid articulations facing mediodistally, as seen in the Early Cretaceous Sinodelphys and other Cretaceous and Paleogene taxa, attest not only to the metatherian status of these specimens, but also to the retention of many ancestral therian features, even more so than in both the Tiupampa and Itaboraí marsupials of the South American Paleocene (both the calcanea and the astragalus suggest therian traits that are decidedly unlike those of symmetrodonts). Calcanea allocated to the deltatherioid species at Bissekty testify unequivocally to their metatherian affinity. The morphology of the best represented sample of eutherian calcanea from Bissekty, presumably of a number of zhelestid species, appears to be more derived than that of the Late Cretaceous/Paleocene Protungulatum in having a much more reduced peroneal process and a calcaneocuboid articulation that faces distally, oriented nearly at a 90° angle to the long axis of the calcaneus. In fact, this distally facing facet, common in later eutherians (except for lineages in the Paleogene record, and various Carnivora), may not be diagnostic of either the protoeutherian, or even of the protoplacentalian, in spite of its presence in Eomaia. Many putatively “basal” lineages have derived characters, hence such outgroups should not be considered the unequivocal repositories of only ancestral character states.


Mammalia Tarsals Character analysis Phylogeny Late Cretaceous Uzbekistan 

Institutional abbreviations


Uzbek/Russian/British/American/Canadian Joint Paleontological Expedition specimens currently at San Diego State University, San Diego


Zoological Institute, Russian Academy of Sciences, Saint Petersburg

Literature cited

  1. Archibald JD, Averianov AO (2003) The Late Cretaceous eutherian mammal Kulbeckia. J Vertebr Paleontol 23:404–419CrossRefGoogle Scholar
  2. Archibald JD, Averianov AO (2005) Mammalian faunal succession in the Cretaceous of the Kyzylkum Desert. J Mamm Evol 12:9–22CrossRefGoogle Scholar
  3. Archibald JD, Averianov AO, Ekdale EG (2001) Late Cretaceous relatives of rabbits, rodents, and other extant eutherian mammals. Nature 414:62–65PubMedCrossRefGoogle Scholar
  4. Asher RJ (2005) Insectivoran-grade placentals. In: Rose KD, Archibald JD (eds) The rise of placental mammals: Origins and relationships of the major extant clades. The John Hopkins University Press, Baltimore and London, pp 50–70Google Scholar
  5. Asher RJ, Novacek MJ, Geisler JH (2003) Relationships of endemic African mammals and their fossil relatives based on morphological and molecular evidence. J Mamm Evol 10:131–194CrossRefGoogle Scholar
  6. Averianov AO, Archibald JD (2003) Mammals from the Upper Cretaceous Aitym Formation, Kyzylkum Desert, Uzbekistan. Creteceous Res 24:171–191CrossRefGoogle Scholar
  7. Bergqvist LP (1996) Reassociação do pós-crânio às espécies de ungulados da bacia de S. J. de Itaboraí (Paleoceno), estado do Rio de Janeiro, e filogenia dos “Condylarthra” e ungulados Sul-Americanos com base no pós-crânio. Ph.D. dissertation, Universidade Federal do Rio Grande do Sul, Porto Alegre, p 407Google Scholar
  8. Bock WJ (1981) Functional-adaptive analysis in evolutionary classification. Am Zool 21:5–20Google Scholar
  9. Cifelli RL (1983) Eutherian tarsals from the late Paleocene of Brazil. Am Mus Novitates 2761:1–31Google Scholar
  10. Ekdale EG, Archibald JD, Averianov AO (2004) Petrosal bones of placental mammals from the Late Cretaceous of Uzbekistan. Acta Paleontol Polon 49:161–176Google Scholar
  11. Horovitz I (2000) The tarsus of Ukhaatherium nessovi (Eutheria, Mammalia) from the Late Cretaceous of Mongolia: An appraisal of the evolution of the ankle in basal therians. J Vertebr Paleontol 20:547–560CrossRefGoogle Scholar
  12. Horovitz I (2003) Postcranial skeleton of Ukhaatherium nessovi (Eutheria, Mammalia) from the Late Cretaceous of Mongolia. J Vertebr Paleontol 23:857–868CrossRefGoogle Scholar
  13. Horovitz I, Sánchez-Villagra MR (2003) A morphological analysis of marsupial mammal higher-level phylogenetic relationships. Cladistics 19:181–212CrossRefGoogle Scholar
  14. Hurum JH, Luo Z-X, Kielan-Jaworowska Z (2006) Were mammals originally venomous? Acta Palaeontol Polon 51:1–11Google Scholar
  15. Ji Q, Luo Z-X, Yuan C-X, Wible JR, Zhang JP, Georgi JA (2002) The earliest known eutherian mammal. Nature 416:816–822PubMedCrossRefGoogle Scholar
  16. Kemp TS (1982) Mammal-like reptiles and the origin of mammals. Academic Press Inc., LondonGoogle Scholar
  17. Kielan-Jaworowska Z (1977) Evolution of the therian mammals in the Late Cretaceous of Asia. Part II. Postcranial skeleton in Kennalestes and Asioryctes. Palaeontol Polon 37:65–83Google Scholar
  18. Kielan-Jaworowska Z (1978) Evolution of the therian mammals in the Late Cretaceous of Asia. Part III. Postcranial skeleton in Zalambdalestidae. Palaeontol Polon 38:5–41Google Scholar
  19. Kielan-Jaworowska Z, Gambaryan PP (1994) Postcranial anatomy and habits of Asian multituberculate mammals. Fossils Strata 36:1–92Google Scholar
  20. Kielan-Jaworowska Z, Cifelli RL, Luo Z-X (2004) Mammals from the age of dinosaurs. Origins, evolution, and structure. Columbia University Press, New YorkGoogle Scholar
  21. Li G, Luo Z-X (2006) A Cretaceous symmetrodont therian with some monotreme-like postcranial features. Nature 439:195–200PubMedCrossRefGoogle Scholar
  22. Luo Z-X, Ji Q, Wible JR, Yuan C-X (2003) An Early Cretaceous tribosphenic mammal and metatherian evolution. Science 302:1934–1940PubMedCrossRefGoogle Scholar
  23. Luo Z-X, Ji Q (2005) New study on dental and skeletal features of the Cretaceous “symmetrodontan” mammal Zhangheotherium. J Mamm Evol 12:337–357CrossRefGoogle Scholar
  24. Luo Z-X, Wible JR (2005) A Late Jurassic digging mammal and early mammalian diversification. Science 308:103–107PubMedCrossRefGoogle Scholar
  25. Matthew WD (1937) Paleocene faunas of the San Juan Basin, New Mexico. Trans Am Philos Soc 30:1–510CrossRefGoogle Scholar
  26. McKenna MC, Bell SK (1997) Classification of mammals above the species level. Columbia University Press, New YorkGoogle Scholar
  27. Mickevich MF, Weller SJ (1990) Evolutionary character analysis: Tracing character change on a cladogram. Cladistics 6:137–170Google Scholar
  28. Miyamoto MM (1996) A congruence study of molecular and morphological data for eutherian mammals. Mol Phylogen Evol 6:373–390CrossRefGoogle Scholar
  29. Murray P, Wells R, Plane M (1987) The cranium of the Miocene thylacoleonid marsupial Wakaleo vanderleuri: click go the shears—a fresh bite at thylacoleonid systematics. In: Archer M (ed) Possums and opossums: studies in evolution, vol 2. Surrey Beatty and Sons, Sydney, pp 433–466Google Scholar
  30. Nessov LA, Archibald, JD, Kielan-Jaworowska Z (1988) Ungulate-like mammals from the Late Cretaceous of Uzbekistan and a phylogenetic analysis of Ungulatomorpha. In: CK Beard, MR Dawson (eds), Dawn of the Age of Mammals in Asia, Bull. Carnegie Mus Nat Hist 34:40–88Google Scholar
  31. Simmons NB (1993) The importance of methods: Archontan phylogeny and cladistic analysis of morphological data. In: MacPhee RDE (ed) Primates and their relatives in phylogenetic perspective. Plenum Press, New York, pp 1–61Google Scholar
  32. Springer MS, Murphy WJ, Eizirik E, O’Brien SJ (2005) Molecular evidence for major placental clades. In: Rose KD, Archibald JD (eds) The rise of placental mammals: Origins and relationships of the major extant clades. The John Hopkins University Press, Baltimore and London, pp 37–49Google Scholar
  33. Szalay FS (1984) Arboreality: Is it homologous in metatherian and eutherian mammals? Evol Biol 18:215–258Google Scholar
  34. Szalay FS (1993) Pedal evolution of mammals in the Mesozoic. In: Szalay FS, Novacek MJ, McKenna MC (eds) Mammalian phylogeny. Mesozoic differentiation, multituberculates, monotremes, early therians and marsupials. Springer-Verlag, New York, pp 108–128Google Scholar
  35. Szalay FS (1994) Evolutionary history of the marsupials and an analysis of osteological characters. Cambridge University Press, New YorkGoogle Scholar
  36. Szalay FS (2000) Function and adaptation in paleontology and phylogenetics: Why do we omit Darwin? Palaeontologia Electronica 3:25 pp., 366KB. Scholar
  37. Szalay FS, Bock WJ (1991) Evolutionary theory and systematics: Relationships between process and patterns. Zeitschrift für Zoologie, Systematik und Evolutionsforschung 29:1–39Google Scholar
  38. Szalay FS, Decker RL (1974) Origins, evolution, and function of the tarsus in late Cretaceous eutherians and Paleocene primates. In: Jenkins Jr FA (ed) Primate locomotion. Academic Press, New York, pp 223–254Google Scholar
  39. Szalay FS, Sargis EJ (2001) Model-based analysis of postcranial osteology of marsupials from the Paleocene of Itaboraí, Brazil, and the phylogenetics and biogeography of Metatheria. Geodiversitas 203:139–302. Scholar
  40. Szalay FS, Schrenk F (1998) The middle Eocene Eurotamandua and a Darwinian phylogenetic analysis of “edentates.” Kaupia 7:97–186Google Scholar
  41. Szalay FS, Trofimov BA (1996) The Mongolian late Cretaceous Asiatherium, and the early phylogeny and paleobiogeography of Metatheria. J Vertebr Paleontol 16:474–509CrossRefGoogle Scholar
  42. Wible JR, Rougier GW, Novacek MJ (2005) Anatomical evidence for superordinal/ordinal eutherian taxa in the Cretaceous. In: Rose KD, Archibald JD (eds) The rise of placental mammals: origins and relationships of the major extant clades. The John Hopkins University Press, Baltimore and London, pp 15–36Google Scholar

Copyright information

© Springer Science+Business Media, LLC 2006

Authors and Affiliations

  1. 1.Department of BiologyUniversity of New MexicoAlbuquerqueUSA
  2. 2.Department of AnthropologyYale UniversityNew HavenUSA

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