Fig. 2

REIMS discrimination of faecal pellets from 5 rodent species under laboratory conditions. REIMS data were collected for faecal pellets from 16 to 20 individuals (including both sexes) for 5 different rodent species. All animals were fed the same base laboratory diet, but wood mice and voles also received supplements. Mass spectra were collected, binned and averaged per individual. a Spectra averaged across individuals of the 5 different species. b Discriminant function analysis of the top 12 principal components for classification of bank voles (BV, orange points), field voles (FV, green points), house mice (HM, purple points), wood mice (WM, blue points) and Wistar × Brown Norway rats (R, red points). c Random forest confusion matrix for species classification, using all data, expressed as the percentage of each species classified correctly or incorrectly (highlighted in blue)