William Theurkauf

between sound and meaning within vast possible variations in the items under comparison, reducing the possibility of chance similarity. In contrast, there is a 'poverty of choice' of some other language features. " For example there are only six permutations for the ordering of the subject, object and verb that a language can use. Accordingly, there is a one in six chance that any two languages share the same ordering — in fact, since some configurations are much more likely than others, even this probability is an underestimate, " they write. This means that, even for a given rate of change, shared features like this " are a less reliable indication of common ancestry than shared basic vocabulary, and are more likely to produce spurious relationships. " A second stumbling block in looking for language features beyond vocabulary is the historical contact between populations speaking different languages leading to a 'diffusion' between the two. This can occur through language shift — where speakers of one language change to another owing to social influences, yet retain morphology or phonology from their original language. Or it can occur where a language rearranges some aspects of structure " without explicit borrowing between the languages, usually as an outcome of intimate cultural contact, " they write. In one cluster in their analyses, Hindi does not group correctly with Indo-European but is located with its geographical neighbour, the Dravidian language, Kannada, suggesting the similarities seen here may indeed be due to diffusion. Likewise a grouping of Indonesian, Thai, Vietnamese and Mandarin may be the result of diffusion in the southeast Asian region. While the team were unable to identify a set of consistently stable structural features, rates of word evolution in Indo-European were a good predictor of rates in the Austronesian group. But the researchers believe deeper structures may yet be revealed. The WALS database is currently " unfortunately sparse " , they write. More data on more languages could reveal greater insight into language evolution. " Our findings highlight how little we know about the shape and tempo of language change. " cellular changes at the midblastula stage' (Cell 30, 675–686); and 'A major developmental transition in early Xenopus embryos II: control of the onset of transcription' (Cell 30, 687–696). I was a first year graduate student when these papers came out, and had a very strong bias toward hard core biochemistry and molecular …