Time Calibration of Linguistic Phylograms: A Molecular Clock for Historical Linguistics
Evolutionary patterns of languages and organisms have surprising similarity, as Darwin famously captured by what he termed as “Curious Parallelism.” While traditional comparative and historical linguistic methods such as detailed analysis of cognate correspondences reveal similarities between languages and group them into linguistic families like how Carl Linnaeus grouped organisms into taxonomical hierarchies based on overall similarity-an approach known as phenetic clustering, this will not help to answer such as “when did Proto-Dravidian split to Proto-South Dravidian and Proto-South-Central Dravidian?” and so on. Conventional methods for dating linguistic trees such as glottochronology are severely flawed such that these have now been largely discredited. Proposed in this invited editorial is the direct extension of the molecular clock hypothesis and time-calibration techniques of molecular phylogenetics to the field of phylolinguistics. For ‘calibration checkpoints’, ancient dated texts, as well as dated and reliable historical information (such as Cro-Magnon migration to Europe, etc.), can be employed. Also deliberated here is a call to make use of Maximum Parsimony-based approaches for the ancient character-state reconstruction, for reconstructing long-lost languages.