A small piece of ivory, about the size of the first digit of your baby finger, is placed in a glass tube, along with a strong magnet. Each end of the tube is plugged with a stainless steel cap, and the assembly is lowered into a vat of liquid nitrogen, which freezes ivory to about minus 240 degrees Celsius. The tube is placed in a machine that shifts a strong magnetic field right and left, causing the magnet in the tube to slide back and forth, smashing the ivory into a fine powder.
"The DNA is perfectly preserved in that process," Wasser says.
The researchers were able to isolate 16 different genes found in each tusk, thus creating a genetic profile of representative samples from a huge seizure of ivory. But where did the ivory come from?
For years the researchers have collected elephant feces from across Africa and extracted the DNA in an effort to produce a genetic map of the continent's elephants. But the computer models used for that sort of mapping have assumed that animals found in adjacent areas would be no more similar to each other than animals found on opposite sides of Africa.
"That's very unrealistic," Wasser says, because animals found nearby are more likely to be closely related so a more generalized map would be more effective. The researchers combined the samples in a new technique, called smoothing, which produce a genetic profile across the entire continent in much less time and with satisfactory precision.
"Once we did that we were able to say for the first time ever where in Africa a DNA sample came from," Wasser says. "That was a huge, huge leap forward."
The result was quite startling. Some 532 tusks seized in Singapore in 2002 did not come from all over Africa, as most people had assumed. All of them came from one relatively small region, centered on Zambia. But even though law enforcement officials now have a specific "hot spot" to concentrate on, not one single person has been prosecuted for poaching.
That has to improve dramatically, Wesser says, or this "keystone species" is doomed.
But at least the research by Wesser's team has shown the way to narrow the battle against killers of endangered species, from tigers to whales. One of the hurdles is it can take years to create a genetic map, and that period needs to be shortened. So the researchers turned to man's best friend for help.
"We train essentially narcotics dogs to find feces of endangered species," he says. They make frequent visits to the dog pound, looking for pooches with a love of tennis balls. They teach the dog to lead them to the desired fecal matter in exchange for a tennis ball.
"Our dogs can find samples from up to 18 different species at once," Wesster says. "And they can smell a sample over a half mile away. We've even trained them to ride on the bow of a boat and to smell killer whale and right whale feces, and direct us to the sample."
When the whale defecates, the smell eventually floats up to the surface, and when the dog smells it he "gets really excited" in anticipation of getting a tennis ball. The dog even shows them the way to find the excrement, because if the boat isn't on the right course the dog loses interest, and the boat is steered one way or the other until the dog is, once again, really happy.
The dogs are a great resource, but they weren't used in Africa.
"Those fecal samples weight 25 pounds," Wasser says, so who needs help?
But for other species, he adds, "dogs have become great partners. They love their job. They spend their day roaming through the woods, smelling poop. What could be better?"