From Sciencedaily.com
"In order to study past environmental changes scientists typically acquire samples from deposits laid down in bogs or lakes, within which organic matter, which can be dated is preserved," explains Dr Carr. "But in dryland environments such as southern Africa this isn't possible. Fortunately it seems that hyrax urine preserves organic matter over timescales of tens of thousands of years, which provides remarkable insights into past environmental changes within the hyrax habitat."
Obtaining the material is not easy and Dr Chase is an experienced rock- climber, which allows him to reach middens that are often otherwise inaccessible. The middens form extremely tough deposits, which have to then be cut from the rocks with an angle grinder.