Growth process in an elephant tusk: Age estimations based on temporal variations in bomb-radiocarbon content

Abstract In this study, 14 C analysis by accelerator mass spectrometry (AMS) was applied to age estimation based on temporal variations in bomb-produced- 14 C contents of a full elephant tusk registered at Kyushu University. The tusk measured 175 cm long and 13.8 cm in diameter at the root. Thirty tusk-fragment samples were used for 14 C analysis with AMS to estimate the formation ages of different positions according to catalogued global 14 C contents (F 14 C). The F 14 C value of the tip of the tusk suggested that the elephant was born around 1980, while that of the root suggested death around 1994, a lifespan of at least 14 years, rather shorter period than the average lifetime of an elephant (ca. 80 years). In addition, the F 14 C values of fragments collected along a cross-sectional line suggested that the outer part of the tusk formed first with inner parts being deposited gradually with growth.