The Answer Lies in the Soils?

Applying DNA 'bar coding' to the faeces of animals, facilitates identifying the host's DNA as well as its diet, gut bacterial flora and its parasite load. The technique has been recently used to differentiate between 3 species of Banded langurs (https://www.theguardian.com/environment/2020/nov/05/how-poo-analysis-could-help-save-endangered-species-aoe). These monkeys generally stay in the tree tops, where they are difficult to observe. Analysis of their faecal droppings has confirmed, however, that two of what were formerly regarded as regional sub-species, are actually distinct species. This now means that these populations can be properly identified as 'at risk' species and resources can be directed to their conservation.