Poaching of elephants in Africa has surged in recent years, driven by ivory prices that have more than quadrupled since 2004. Bans on killing elephants are difficult to enforce, partly because authorities don't often know where on the vast continent the poaching is happening.
Scientists had previously attempted using DNA analysis to trace the origins of confiscated tusks, but the information was too imprecise to aid law enforcement. Now, scientists have demonstrated that they can trace the ivory to a single country.
In 2002, police seized more than 6.5 tons of illegal ivory in Singapore. Interpol, an organization that coordinates international police forces, asked Samuel K. Wasser of the University of Washington in Seattle to investigate the source of the ivory.
Wasser and his colleagues adapted the existing technique to work for batches of ivory rather than for single tusks. They compared DNA from each of 37 seized tusks with that from the other samples.