Evolution What the Fossils Say and Why it Matters

FIGURE 13.9. The skulls of some of the better known Mesozoic mammals. (A) Early Jurassic Sinoconodon. (B)
Early Jurassic Morganucodon. (C) Early Cretaceous Vincelestes. (D) The Paleocene multituberculate Ptilodus,
representative of the long-lived Mesozoic radiation of multituberculates. Abbreviations: sq-den jt, squamosal-
dentary joint; ref lam, reflected lamina; art, articular bone; m1, first lower molar; p4, fourth lower premolar.
(From Hopson 1994: fig. 9; courtesy J. Hopson)

(A) (B)

(C) (D)

sq-den jt

m1

art

sq-den jt

ref lam

p4

m1

m1

FIGURE 13.10. The beautifully preserved complete fossil of the oldest known marsupial, Sinodelphys szalayi, from
the Lower Cretaceous of China. (A) The complete skeleton of the type specimen. (B) Artistic reconstruction by
Carl Buell of the appearance of Sinodelphys. See Luo et al. (2003: 1934–1940). (Courtesy Zhexi Luo/Carnegie
Museum of Natural History)

(A)

http://www.ebook3000.com