Although wooly mammoths are long gone, their recovered ivory lives on as a legal alternative to banned elephant ivory. Scientists can now use lasers to differentiate between the two materials, hopefully reducing the revenue stream for poachers.
In order to protect dwindling elephant populations, the international trade in ivory was banned in 1990. Given the fact that the trade in extinct mammoth ivory remained legal, however, some people began commercially harvesting mammoth tusks from the Arctic tundra.
The problem is, many poachers who live far from the Arctic continue to hunt and kill elephants. Sometimes the animals' ivory is sold on the black market as elephant ivory. Other times, however, it gets carved into the form of figurines or other products, then fraudulently sold through legitimate channels as mammoth ivory.
Unfortunately for customs officials, analyzing ivory to determine which species it comes from is a complex and time-consuming task, plus it involves destroying a sample of the material. That's where the lasers come in.
Led by the University of Bristol's Dr. Rebecca Shepherd, scientists from that institution and the University of Lancaster set out to see if a non-destructive technique known as Raman spectroscopy could be utilized.
Putting it simply, Raman spectroscopy involves shining monochromatic laser light onto a sample of material. The molecules in that substance vibrate in response, scattering the light in a unique manner. Therefore, by analyzing that scattered light, it's possible to ascertain which chemicals are present in the sample.
In lab tests, the scientists scanned samples of mammoth and elephant ivory provided by the Natural History Museum in London. The process took just a few minutes, and proved capable of detecting small biochemical differences that could reliably be used to tell the two types of ivory apart.
"Raman spectroscopy can provide results quickly […] and is easier to use than current methods, making it easier to determine between illegal elephant ivory and legal mammoth tusk ivory," says Shepherd. "Increased surveillance and monitoring of samples passing through customs worldwide using Raman spectroscopy could act as a deterrent to those poaching endangered and critically endangered species of elephant."
A paper on the research was recently published in the journal PLOS ONE.
Source: University of Bristol