title: Humidity as a source of measurement error in osteometrics.
abstract: A simple experiment was conducted to test the hypothesis that variation in humidity causes expansion of bone and, thereby, affects measurements of dried, preserved skulls. The experiment consisted of subjecting ten macaque skulls to increased humidity for 24 hours. Measurements of nine skull dimensions taken immediately before and after humidification revealed a statistically significant treatment effect of increased skull size with increased humidity. The length of the molar tooth row increased by about 0.1 mm (0.50%) while the greatest length of the skull increased by about 0.9 mm (0.57%). The specimens returned to their original dimensions within 1-2 days after being removed from the humidity chamber. These results confirm the impression gained by the practical experience of measuring museum specimens in different locations and environments. It appears that bony changes associated with humidity differences represent a real, though minor, source of measurement error in osteometrics.
mesh_terms: D000818:Animals; D002508:Cephalometry / Q000379:methods*; D005260:Female; D006813:Humidity; D008251:Macaca; D008254:Macaca nemestrina; D008297:Male; D012886:Skull / Q000033:anatomy & histology; D013045:Species Specificity