The Pacific area is generally acknowledged to manifest great linguistic diversity. Such diversity is generally assumed to be dysfunctional, an obstacle to efficient functioning of society. Such diversity must, however, have its functions at least in the circumstances in which it arose. It is also generally assumed that such diversity is the result of a communication density too slight to permit uniformity to be maintained. However, in numerous actual cases, feeble communication density seemingly cannot be the explanation for persistent diversity. Therefore two assumptions can be made: (1) an ongoing process of diversification led gradually to the present level of diversity, and (2) this diversification cannot reasonably be attributed to isolation. It can therefore be assumed that diversity itself may in some circumstances offer selective advantages. Only some very inconclusive suggestions concerning such advantages can be made at present. However, it also seems that different kinds of diversity should be distinguished, and that some may not be as onerous as has been assumed. (Author/AM)