The international ivory trade was banned in 1989, but estimates are that about 30,000 elephants are still killed each year for their tusks. It can be difficult for anti-poaching workers to figure out whether ivory was obtained legally before the ban or if it's newer. Researchers have developed a way to carbon-date the tusks that might be able to help pinpoint the illegal ivory.
As researcher Kevin Uno explains in Mother Jones, "new tissue forms every day in the elephant's tusk as it eats, with the base containing the newest tissue. Because the carbon absorbed by plants contains radiocarbon from the atmosphere, researchers can match the radiocarbon level in the tissue."
An international team of scientists, including Dr. Uno, determined that the answer can be found with a test measuring the level of radioactive carbon in a piece of ivory.
Atmospheric radiocarbon has been at an especially high level since nuclear weapons testing by the United States and Soviet Union in the 1950s. The radioactive element has been degrading ever since. By matching the amount of radiocarbon in a tusk with the amount in the atmosphere at a given time, the researchers can tell when the tusk grew - and when the elephant was killed.
The findings were published in the Proceedings of the National Academy of Sciences (PNAS). VOA reports that the technique can also be used on other materials, such as rhinoceros horns. The article states that elephants and rhinoceroses are both at risk of becoming extinct due to poaching.
This week, the Obama Administration announced an executive order that VOA reports dedicates $10 million to benefit anti-poaching efforts in sub-Saharan Africa.
Photo credit: Elephant statue at the National Zoo in Washington, D.C. by sharowitz