. The brain in hominid evolution. Human evolution; Brain; Fossil hominids. tissue: estimates of this proportion vary. On the one hand we have Wingate Todd's (1923, p. 265) statement, "Of course it is impossible to ascertain how fully the brain ever occupies the total possible space at its ; On the other hand figures are cited ranging from 10 per cent (Brandes 1927) to as high as 33% per cent (cited by Mettler in his 1955 James Arthur Lecture). Cranial capacity is therefore only an approximation to the size of the brain itself. It might be deemed that we could simply apply a
. The brain in hominid evolution. Human evolution; Brain; Fossil hominids. tissue: estimates of this proportion vary. On the one hand we have Wingate Todd's (1923, p. 265) statement, "Of course it is impossible to ascertain how fully the brain ever occupies the total possible space at its ; On the other hand figures are cited ranging from 10 per cent (Brandes 1927) to as high as 33% per cent (cited by Mettler in his 1955 James Arthur Lecture). Cranial capacity is therefore only an approximation to the size of the brain itself. It might be deemed that we could simply apply a correction factor to the determined capacity in order to ascertain the brain size. Un- fortunately, the wide discrepancy between the 2 extreme figures cited—10 per cent and 33% per cent—would vitiate such a correction. Furthermore, the ratio is not a constant figure within the adult lifetime of any one individual, for the brain shrinks with age, in certain illnesses, and under some other. Figure 8: Antero-superior view of a natural endocast of a presumed Austra- lopithecus africanus from Sterkfontein. The pointers indicate a pair of localized impressions where the surface of the endocast drops below the surrounding intact surface, consequent upon a doubly indented de- pressed fracture of the cranium. All trace of bone has since disappeared, leaving only the indented surface of the endocast. 9^. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Tobias, Phillip V. New York : Columbia University Press
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Keywords: ., boo, bookcentury1900, booksubjectbrain, booksubjecthumanevolution
