Department of Geology and Geophysics, University of Utah, Salt Lake City, UT 84112.
School of Biological Sciences, University of Utah, Salt Lake City, UT 84112.
Proc Natl Acad Sci U S A. 2022 Nov;119(44):e2211550119. doi: 10.1073/pnas.2211550119. Epub 2022 Oct 17.
The 14-carbon in animal tissues records the time that the tissues are formed; since the 1960s, using the "bomb curve" for C, the age of animal death can be determined accurately. Using animal tissue samples of known collection and formation dates for calibration, we determine the age of ivory samples from four ivory seizures made by law enforcement agencies between 2017 and 2019. The C measurements from these seizures show that most ivory in the illegal wildlife trade is from animals from recent poaching activities. However, one seizure has a large fraction of ivory that is more than 30 y old, consistent with markings on the tusks indicating they were derived from a government stockpile.
动物组织中的 14 碳记录了组织形成的时间；自 20 世纪 60 年代以来，通过使用 C 的“炸弹曲线”，可以准确确定动物的死亡时间。我们使用已知采集和形成日期的动物组织样本进行校准，确定了 2017 年至 2019 年执法机构查获的四起象牙样本的年龄。这些查获样本的 C 测量结果表明，非法野生动植物贸易中的大多数象牙来自最近的偷猎活动的动物。然而，有一起查获的象牙中有很大一部分超过 30 年，与象牙上的标记一致，表明它们来自政府的库存。
