Determining bat relatedness using PCR

Within the past few years, biologists have begun to look for noninvasive techniques for studying bat genetics.  One of the methods that was considered was the use of PCR.  A study by Puechmaille et al., showed that by collecting bat droppings and extracting their DNA, PCR techniques could be used to study the genetic relatedness of individual bats within a large colony in a noninvasive matter.  One challenge with this technique is that dropping samples must be collected on a relatively clean surface.  So in their study, Puechmaille and colleagues removed a layer of soil and placed newspaper under a roosting bat colony.  In an effort to retrieve accurate data, the papers had to be checked and retrieved often so as not to become too densely populated with fecal material, thus compromising individual results.