Another, more elaborate phylogenetic study on all of the endemic Filipino genera and species of Murinae, of which the large Mindoro forest mouse is a member, produced different results. According to this study, the "Chromotys" division originated some ten million years ago (rather than the estimate of six million years ago from the previous study). It was further calculated that the split between the "Chromotys" division and its closest relatives, a predominantly African group including "Mus", "Otomys" and "Mastomys", had happened about sixteen million years ago. However, since the fossil record of "Murinae" from the Philippines is non-existent, and controversial for Murinae from other areas, these estimates can only be based on the molecular clock, and not on direct paleontological data.