The structure and dimensions of the lumbar vertebrae from 18 genera of African bovids (with a body weight range of 4–900 kg) were studied with reference to allometric and biomechanical factors. Centrum height scales with body weight according to McMahon's elastic similarity theory, but centrum width scales geometrically with body weight. Thus, the dimensions of bones need not scale according to a single principle. Transverse process orientation, as measured in two planes, varies allometrically with body weight; this trend may reflect size‐related differences in abdominal girth and spinal musculature. Bovids exhibit decreasing lumbar mobility in the sagittal plane with increasing body size, a phenomenon related to an increase in centrum height and the appearance of interlocking mechanisms (postzygapophysial ridges and prezygapophysial labra). Geometric scaling of centrum width and zygapophysial curvature is evidence that lateral flexion of the spine occurs throughout the family. In all taxa examined, the last lumbar vertebra exhibits an absolutely wider centrum and straight postzygapophyses, thus reducing lateral mobility at the lumbosacral joint. In heavier bovids, the observed restriction of lumbar flexion and extension to the lumbosacral joint is a consequence of the distribution of the shapes of the centra and the interlocking mechanisms of the zygapophyses.

All mammals have the same divisions of cyclic movement of tongue and hyoid during mastication: a protraction or forward phase that begins at minimum gape, and a retraction or return phase. Nonanthropoid mammals transport food from the oral cavity to the oropharynx during the return phase; food on the dorsal surface of the tongue moves distally while the tongue is retracted. Macaques, however, transport food during the protraction phase of tongue/hyoid movement. Food is squeezed posteriorly by contact between the tongue surface and the palate anterior to the food. This mechanism of transport is occasionally seen in nonanthropoid mammals when they are transporting liquids from the oral cavity to the oropharynx. It has, however, not been seen when these mammals transport solid food. One morphological basis for this difference is the reduction in height of the rugae of the palate of macaques. In most mammals these rugae are pronounced ridges that are able to hold food in place during protraction as the tongue slides forward beneath the food. Anthropoids and other mammals differ in the way they store food prior to swallowing. When macaques transport food to the oropharynx, usually they swallow in the next cycle, but always in the next 2 or 3 cycles. Most mammals transport and store food in the oropharynx for several cycles before a swallow clears that region of food. This behavior is correlated with differences in morphology of the oropharynx; anthropoids have reduced valleculae, the area in which other mammals store food prior to swallowing.

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The anatomical structures used during mammalian feeding are morphologically linked by their connecting musculature, suggesting a predictable timing relationship among their movements. Cine-x-ray (100 frames per second) was used to record feeding behavior in four adult hyraxes (Procavia syriacus), herbivores. Movement of jaws, tongue, and hyoid bone was cyclic, and prior to the first swallow cycle, cycle duration was constant through time for all structures. Minimum gape, beginning of forward movement of the tongue and hyoid, and beginning of intrinsic tongue expansion occurred simultaneously over a large number of cycles. However, maximum gape, maximum protrusion of hyoid, and maximum forward position of the tongue happened at statistically different points in time. After the first swallow, cycle duration increased. Most of the variation in cycle duration can be explained by variation in the opening or forward phase of movement; the closing and return phases are constant in duration. These results are a quantitative description of the coordination that exists during different feeding behaviors (ingestion, intraoral transport, mastication, and swallowing) in normal, freely functioning hyraxes. The patterns of phase duration differ from some results obtained by using anesthetized animals.