Bone histomorphology of the Dederiyeh Neanderthal child

Abstract

To clarify bone formation and growth in Neanderthal children, we prepared a femoral midshaft cross-section of the Dederiyeh 1 Neanderthal child (ca. 2 years old) discovered in Syria, and compared its bone histomorphology with that of modern children aged 0-6 years. Bone histomorphometry was performed with regard to six parameters, i.e. cortical width, percent osteonal bone, osteon population density, non-Haversian canal population density, secondary osteon area, and Haversian canal area. Dederiyeh 1 had thick cortical bone similar to the mean of modern children aged 5-6 years, and advanced secondary bone formation, which was represented by greater percent osteonal bone and osteon population density than in 2-year-old modern children. However, primary bone configuration scarcely differed between Dederiyeh 1 and modern 1-to 2-year-olds. The histomorphology of the Dederiyeh 1 femur can be characterized as a complex of features seen in modern children at different ages, which suggests that cortical bone formation in Dederiyeh 1 was different from that in modern children. A variety of causes, such as mechanical loading, genetic control, and abnormal metabolism, are plausible, but it is not possible to determine which of these factors most affected bone formation in Dederiyeh 1.

The Neandertals of northeastern Iberia: New remains from the Cova del Gegant (Sitges, Barcelona)

“…Although Neandertal humeri from children of similar age as the Gegant-4 specimen are rare, the present results agree with previous studies suggesting that the thick cortical bone characteristic of adult Neandertal humeri is also present at an early ontogenetic age (Ruff et al, 1994;Sawada et al, 2004;Arsuaga et al, 2007;Cowgill, 2010). Whether this is caused by mechanical loading, genetic control, or metabolic differences between populations is currently unclear.…”

“…Adult Neandertal long bones are characterized by a pronounced hypertrophy of the cortical bone (Trinkaus, 1983), and this feature is known to appear relatively early in ontogeny (Ruff et al, 1994;Cowgill, 2010). For example, in the Dederiyeh 1 Neandertal infant, whose age at death has been estimated at around 2 years based on dental formation, the cortical bone thickness is similar to the mean of modern human children aged 5e6 years (Sawada et al, 2004). It is not surprising, then, that the cortical thickness in the Gegant-4 humerus appears elevated for its age, compared with recent humans.…”

Secondary osteon and Haversian canal dimensions as behavioral indicators

“…The LSA values for On.Ar are smaller than those that were published for adult femora from Pecos Pueblo (males, 41,328 lm 2 ; females, 35,288.9 lm 2 ) (Abbott et al, 1996), and are much smaller than values from a small number of secondary osteons measured in 15 modern juvenile femora (with values ranging from approximately 35,000-45,000 lm 2 ) (Sawada et al, 2004). Given the large amount of variability in On.Ar at the levels of the bone, the individual, and the group, we may be some distance from having a firm sense of its central tendency in human cortical tissue.…”

“…However, as osteon and Haversian canal areas were reported from a number of more recent samples, the reported variance among modern humans increased substantially, and the Late Pleistocene values were no longer distinct (Pfeiffer, 1998). A recent study of femoral cortical bone from a Neanderthal child of about 2 years of age reported secondary osteons and Haversian canals that were comparable in size to those of a small sample of cortical tissue from modern children (Sawada et al, 2004).The potential existence of patterned differences in osteon size has been a concern to researchers developing histological methods of estimating age at death. Bones with generally larger or smaller osteons may demonstrate different osteon population densities, and would therefore reach asymptotes at different ages.…”

Tubular anomalous bones found in both thighs of a long-tailed macaque (Macaca fascicularis)

“…Micrographs were taken using a microscopic digital camera (Pro-600ES, Pixera), and histomorphometry was performed using image-analysis software (Image J, US National Institutes of Health). Based on the methods of Pfeiffer (1998) and Sawada et al (2004), the osteon and the Haversian canal areas were measured in the secondary osteon region, which is devoid of deformation by remodeling.…”