The OJ Simpson trial put DNA testing as a forensics tool in the spotlight. Now DNA's use in identifying criminals is nothing new, but what is new is its use to identify a different kind of criminal--elephant poachers.

In the 1980's, the number of African elephants dropped from 1.3 million to about 500,000. In order to protect the elephants, an international ban on the selling of African ivory was implemented, but that didn't stop poachers.

One difficulty law enforcers face in tracking poachers is that it's difficult to know where exactly poaching is most concentrated. That's where DNA testing comes in.

There are two different species of African elephant, savanna elephants, which inhabit the grassy plains and bushland, and forest elephants, which live in the equatorial forests. DNA testing can distinguish not only the ivory of savanna elephants from that of forest elephants, but it can to a large degree decipher what region an elephant comes from.

All that genetic testing requires is a small sample from the core of an elephant tusk, about the size of a kernel of corn. Ivory tusks are teeth, and they're made of a material called dentin. Because dentin is secreted by cells in the jaws, scientists predicted that DNA from these cells might be found inside the dentin.

They did indeed find DNA in the tusks and by comparing it to a database of elephants from across the continent of Africa, they've been able to locate where the elephant comes from. This enables law enforcers to concentrate their efforts in regions where poaching is most threatening. It's yet another example of DNA's use in solving crimes.