This video describes the technology of metabarcoding, which allows scientists to determine herbivore diets based on the sequences of plant DNA extracted from animal dung.

Ecologist Robert Pringle describes how he uses DNA metabarcoding in his research. He sequences segments of DNA (the barcodes) from animal dung and matches them to sequences found in a reference library of plant DNA, in order to identify the plant species that the animal ate. This technique has allowed Pringle and colleagues to determine that not all grazers or browsers eat the same plants and to obtain a more accurate picture of how herbivores partition ecological niches by diet.

This clip is from a 2015 Holiday Lecture Series, Patterns and Processes in Ecology.