IB 173/173L 


Handout materials for lecture topic on the transition from reptiles to mammals, including reference list, mammalian ordinal classifications following Simpson (1945) and McKenna and Bell (1997), and  illustrations of transitional steps.

Figure - Phylogeny of amniotes and cladogram of synapsids (mammal-like reptiles and mammals)

individual articles:
  • Ruben, J.A., A.F. Bennett, and F.L. Hisaw. 1987. Selective factors in the origin of the mammalian diaphram. Paleobiology 13:54-59. 
  • Hopson, J.A. 1987. The mammal-like reptiles. The American Biology Teacher 49(1):16-26. 
  • Jenkins, F.A., Jr. 1990. Monotremes and the biology of Mesozoic mammals. Netherlands Journal of Zoology 40(1-2):5-31. 
  • Smith, K.K. 1992. The evolution of the mammalian pharynx. Zoological Journal of the Linnean Society 104:313-349. 
  • Kielan-Jaworowska, Z. 1992. Interrelationships of Mesozoic mammals. Historical Biology 6:185-202. 
  • Zimmer, C. 1994. The importance of noses. Discover Magazine, August 1994. 
  • Hillenius, W.J. 1994. Turbinates in Therapsids: evidence for Late Permian origins of mammalian endothermy. Evolution 48:207-229. 
  • Ruben, J.A. 1995. The evolution of endothermy in mammals and birds: from physiology to fossils. Ann Review of Physiology 57: 69-95. 
  • Hayes, J.P., and T. Garland, Jr. 1995. The evolution of endothermy: testing the aerotic capacity model. Evolution 49: 836-847. 
  • Rowe, T. 1996. Coevolution of the mammalian middle ear and neocortex. Science 273: 651-654. 
edited volumes:
 1. Lillegraven, J.A., Z. Kielan-Jaworowska, and W.A. Clemens (eds.). 1979. Mesozoic mammals. The first two-thirds of mammalian history. University of California Press, Berkeley. 
    a) Crompton, A.W., and F.A. Jenkins, Jr. 1979. Origins of mammals. 
    b) Lillegraven, J.A. 1979. Reproduction in Mesozoic mammals. 
2. Schmidt-Nielsen, K., L. Bolis, and C.R. Taylor (eds.). 1980. Comparative physiology: primitive mammals. Cambridge University Press, London. 
a) Crompton, A.W. 1980. Biology of the earliest mammals. 
b)Taylor, C.R. 1980. Evolution of mammalian homeothermy: a two-step process? 
3. Hotton, N., III, P.D. MacLean, J.J. Roth, and E.C. Ruth (eds.). 1986. The ecology and biology of mammal-like reptiles. Smithsonian Press, Washington D.C. 
a) Ulinski, P.S. 1986. Neurobiology of the therapsid-mammal transition. 
b) Bennett, A.F., and J.A. Reuben. 1986. The metabolic and thermoregulatory status of therapsids. 
c) Duval, D. 1986. A new question of pheromones: aspects of possible chemical signaling and reception in the mammal-like reptiles. 
d) Guillette, L.J., Jr., and N. Hotton, III. 1986. The evolution of mammalian reproductive characteristics in therapsid reptiles. 
4. Szalay, F.S., M.J. Novacek, and M.C. McKenna (eds.). 1993. Mammal Phylogeny. Mesozoic differentiation, multituberculates, monotremes, early therians, and marsupials. Springer-Verlag, New York. 
a) Rowe, T. 1993. Phylogenetic systematics and the early history of mammals. 
b) Luckett, W.P. 1993. An ontogenetic assessment of dental homologies in therian mammals. 
c) Cifelli, R.L. 1993. Theria of metatherian-eutherian grade and the origin of marsupials. 


Ordinal Classification of Mammals (from Simpson, 1945)


Subclass Prototheria

          1.Order Monotremata - platypus, echidna (M Cret - Recent)
Subclass Allotheria
          2. Order Multituberculata* (U Jur - Eoc) incertae sedis
          3. Order Triconodonta* (U Tri - L Cret) 
          4. Order Docodonta* (U Tri? - U Jur)
Subclass Theria 
    Infraclass Pantotheria
          5. Order Symmetrodonta* (U Tri - L Cret) 
          6. Order Pantotheria (=Eupantotheria)* (U Jur - L Cret)
    Infraclass Metatheria 
          7. Order Marsupialia - marsupials (U Cret - Recent)
    Infraclass Eutheria 
      Cohort Unguiculata 
          8.Order Insectivora - shrews, moles, etc. (U Cret - Recent) 
          9. Order Dermoptera - colugos (Paleo - Recent) 
          10. Order Chiroptera - bats (Eoc - Recent) 
          11.Order Primates - lemurs, tarsiers, monkeys (Paleo - Recent) 
          12. Order Tillodontia* - (Paleo - Eoc) 
          13. Order Taeniodonta* - (Paleo - Eoc) 
          14.Order Edendata (=Xenarthra) - sloths, anteaters, armadillos (Paleo - Recent) 
          15. Order Pholidota - pantolin (Pleisto - Recent)
      Cohort Glires 
          16. Order Rodentia - rodents (Paleo - Recent) 
          17.Order Lagomorpha - pikas, rabbits, hares (Eoc - Recent)
      Cohort Mutica 
          18. Order Cetacea - whales, porpoises (Eoc - Recent)
      Cohort Ferungulata 
        Superorder Ferae 
          19.Order Carnivora - dogs, cats, hyaenas, etc. (Paleo - Recent) 
          20.Order Pinnipedia - seals, sealions, etc. (Mio - Recent)
        Superorder Protoungulata 
          21. Order Condylarthra* - (Paleo - Eoc) 
          22. Order Litopterna* - (Paleo - Pleisto) 
          23. Order Notoungulata* - (Paleo - Pleisto) 
          24. Order Astrapotheria* - (Eoc - Mio) 
          25. Order Tubulidentata - aardvark (Eoc? - Recent)
        Superorder Paenungulata 
          26. Order Pantodonta* - (Paleo - Oligo) 
          27. Order Dinocerata* - (Paleo - Eoc) 
          28. Order Xenungulata* - (Paleo) 
          29. Order Pyrotheria* - (Eoc - Oligo) 
          30. Order Proboscidea - elephants (Eoc - Recent) 
          31. Order Embrithopoda* - (Oligo) 
          32.Order Hyracoidea - hyraxes or conies (Oligo - Recent) 
          33. Order Desmostyliformes* - (Mio - Plio) 
          34. Order Sirenia - sea cows, dugongs (Eoc - Recent)
        Superorder Mesaxonia 
          35.Order Perissodactyla - horses, tapirs, rhinos (Eoc - Recent)
        Superorder Paraxonia 
          36.Order Artiodactyla - pigs, hippos, camels, deer, antelopes, cows, goats, etc. (Eoc - Recent)
* = extinct 

Ordinal Classification of Mammals (from McKenna and Bell, 1997)
[equivalents to Simpson's Orders are in all caps]


Class Mammalia 

    Subclass PROTOTHERIA 
      Order Platypoda 
      Order Tachyglossa
    Subclass Theriiformes 
      Infraclass Allotheria 
      Infraclass TRICONODONTA 
      Infraclass Holotheria 
        Superlegion Kuehneotheria 
        Superlegion Trechnotheria 
           Legion SYMMETRODONTA 
           Legion Cladotheria 
        Supercohort Theria 
          Cohort MARSUPIALIA 
            Magnaorder Australidelphia 
            Magnaorder Ameridelphia
          Cohort Placentalia 
            Magnorder XENARTHRA (=EDENTATA) 
              Order Cingulata 
              Order Pilosa 
            Magnorder Epitheria 
               Grandorder Anagalida 
              Mirorder Macroscelidea
              Mirorder Duplicidentata 
                Order LAGOMORPHA
              Mirorder Simplicidentata 
                Order RODENTIA 
               Grandorder Ferae 
              Order Cimolesta 
                Suborder PHOLIDOTA 
              Order CARNIVORA 
                Suborder Feliformia 
                Suborder Caniformia 
               Grandorder Lipotyphla 
              Order Chrysochloridea 
              Order Erinaceomorpha 
              Order Soricomorpha 
               Grandorder Archonta 
              Order CHIROPTERA 
              Order PRIMATES 
                Suborder DERMOPTERA 
                Suborder Euprimates 
              Order Scandentia 
               Grandorder Ungulata 
              Order TUBULIDENTATA 
              Order Cete (includes CETACEA) 
              Order ARTIODACTYLA 
              Order PERISSODACTYLA 
              Order Uranotheria 
                Suborder HYRACOIDEA 
                Suborder Tethytheria 
                  Infraorder SIRENIA 
                  Infraorder Behemota (includes PROBOSCIDEA) 

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