A longitudinal study on hand and wrist skeletal maturation in chimpanzees ( Pan troglodytes ), with emphasis on growth in linear dimensions

Abstract

Skeletal maturation in the chimpanzee hand and wrist (the RUS system; radius, ulna, and short bones) was studied both longitudinally and cross-sectionally. Maturity states were evaluated in each of the 13 bones of the RUS system based on the TW2 method (Tanner and Whitehouse method), and the RUS score was calculated by the summation of scores for these bones. Individual variation was examined by means of residual curves and pseudo-velocity curves of RUS score and anterior trunk length (ATL). Norms of the age change pattern in RUS skeletal maturation and the growth of ATL were determined for each sex, and the relationships among ATL growth and skeletal and reproductive maturation were examined. We found a fairly good relationship between ATL growth and RUS skeletal maturation. Comparison of growth and development between humans and chimpanzees showed that growth characteristics are coupled with each other at puberty in male chimpanzees and in both sexes of humans. Although nutritional condition influenced ATL growth in infancy, it had no effect on the RUS maturational process. Social relationships appeared to influence both ATL growth and RUS maturation. Analyses on relationships between RUS skeletal maturation, ATL growth, and reproductive maturation, showed that RUS skeletal maturation is a good indicator of "physiological age".

Reconstruction of periodicity of repetitive linear enamel hypoplasia from perikymata counts on imbricational enamel among dry‐adapted chimpanzees (Pan troglodytes verus) from Fongoli, Senegal

“…The last event, aggression on him by an adult male, occurred just months before his death and so cannot be linked to the stress recorded on his canine crown which formed earlier in life. Using maturity indicators provided for captive or wild chimpanzees of known age (Nissen and Riesen, 1964;Conroy and Mahoney, 1991;Hamada et al, 1998;Hamada et al, 2003;Zihlman et al, 2007), Frito at the time of his death in 2010 must have been older than 8 years and younger than 13.5. There were times when he spent half an hour whimpering and/or screaming for either his mother or others to wait for him or simply because it hurt to walk.…”

“…After Frito's death, a video recording was made of his exhumed skeleton. Using maturity indicators provided for captive or wild chimpanzees of known age (Nissen and Riesen, 1964;Conroy and Mahoney, 1991;Hamada et al, 1998;Hamada et al, 2003;Zihlman et al, 2007), Frito at the time of his death in 2010 must have been older than 8 years and younger than 13.5. His lower third molar was still deep in its crypt and partially overhung by bone indicating an age of \9.0-11.1 years (Nissen and Riesen, 1964 captives) while his canines were partially erupted suggesting an age [10.5-13.5 (Zihlman et al, 2007 wild animals).…”

Effects of aging on hematology and serum clinical chemistry in chimpanzees (Pan troglodytes)

“…To further evaluate the relationship to age, the mean values for each age year (up to 46 years in females and up to 36 years in males) were compared with the mean at age 11 years. This age (11 years) was chosen as it represents the median age of skeletal [Gavan, 1953;Hamada et al, 2003], dental [Anemone et al, 1991;Kuykendall & Conroy, 1996;Smith et al, 1994], body weight [Leigh & Shea, 1996], and reproductive [Littleton, 2005;Marson et al, 1991;Roof et al, 2005] maturity for captive chimpanzees. The data were pooled across individuals, however, all ages contained a minimum of five datapoints per sex (females 5 25.9713.7 datapoints per age year, males 5 19.0711.9 datapoints per age year).…”

The postcranial skeletal maturation ofAustralopithecus sediba

“…The correlation between skeletal age and body length of chimpanzees is not known. Hamada et al () studied RUS development in seven female and five male captive chimpanzees. They write that they, “…found a fairly good relationship between…” anterior trunk length (measured as the distance from the cranial tip of the sternum to the cranial tip of the pubic symphysis) and RUS score, but they do not provide the statistical strength of the relationship.…”