. Guide leaflet. Johns HopkinsUniversity and described by him in his book on The Evolution of FacialMusculature and Facial Expression (1931). C44: EVOLUTION OF THE HUMAN SKI I I. (CASKS \\, XlIA AM) 20) During the evolution of the skull from rhar of a priniirivc lol)c-finnc(] fishto that of man (Fig. 23), many changes have taken place in the number,proportions and relations of the bones. In the skull of the primitive Devonian fish, Eustbcnopteron, there areabout 145 bones, while in man (Fig. 22) the number is reduced to 27 orfewer. In the living codfish the skull is made up of 68 bones, not in
. Guide leaflet. Johns HopkinsUniversity and described by him in his book on The Evolution of FacialMusculature and Facial Expression (1931). C44: EVOLUTION OF THE HUMAN SKI I I. (CASKS \\, XlIA AM) 20) During the evolution of the skull from rhar of a priniirivc lol)c-finnc(] fishto that of man (Fig. 23), many changes have taken place in the number,proportions and relations of the bones. In the skull of the primitive Devonian fish, Eustbcnopteron, there areabout 145 bones, while in man (Fig. 22) the number is reduced to 27 orfewer. In the living codfish the skull is made up of 68 bones, not includingthe hvoid and branchial arches. This reduction in number, as \\ ell as the striking great increase in thesize of the brain-case and the reduction in the size of the jaws, well illus-trates the principle recognized bv Stromer and Williston, that as we passfrom primitive to specialized vertebrates the number of primary skull ele-ments is reduced, \\ hile those that remain become more highl\- Fig. 22. DISARTICULATED HUiVIAN SKULL, EXCLUSI\^E OF HYOIDAND LARYNGEAL ELEMENTS 1:453 ( r •mi
Size: 1609px × 1552px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1900, bookdecade1900, booksubjectnatural, bookyear1901
