"The circularity of the ‘Ancestral North Indians’ (ANI) vs ‘Ancestral South Indians’ (ASI) concept is another case in point. Reich (2018) admits that he thought it up overnight simply to avert serious differences with his Indian collaborators. No precise definition was ever given to these two supposedly highly distinct groups; they were simply stated to be ‘genetically divergent’ (Reich et al. 2009) and were used in several subsequent studies as though they had been rigorously established. Elsewhere (Danino 2014), I showed that the populations sampled were very seriously restricted, since 18 states of India had either no representation or only one group represented in the 2009 study. Despite such a skewed distribution, Reich et al. exuded confidence in the newly coined terms and found it ‘tempting to assume that the population ancestral to ANI and CEU [Europeans] spoke ‘‘Proto-Indo-European’’ … ’ (Reich et al. 2009, p. 492) – a gratuitous association built, again, on circularity."