by Aaron G. Filler, MD, PhD
Figure 10-3 - Lumbar X-rays in Chimpanzee and Humans.
A – Adult chimpanzee spine demonstrating “ultra-short” free lumbar region with four lumbar vertebrae. The ribs approach the iliac crests. L2, L3 and L4 are between the elongated iliac crests (see also figure 12-4) .
B – Human with four lumbar vertebrae showing an effective long flexible lumbar spine despite decreased number of lumbar vertebrae. This individual has had a surgical technical error with unintended and unproductive placement of an anterior surgical fusion plate between S1 and S2 .
C & D - Humans with six lumbar vertebrae including partial or “transitional” L1 bearing unilateral small rib on the right in (C).
A - Photography from: Filler, A. G. (1979). Functional and Evolutionary Perspectives on Chimpanzee Thoracolumbar Musculature. Masters Thesis, unpublished. Department of Anthropology. Chicago, Illinois, University of Chicago.
B - Photograph from: Filler, A. G. (2007a). Homeotic evolution in the Mammalia: Diversification of therian axial seriation and the morphogenetic basis of human origins. (forthcoming).
C/D - Photographs by Aaron G. Filler © Copyright Aaron G. Filler (2007) The Upright Ape: A New Origin of the Species. Franklin Lakes, New Jersey; New Page Books.