  Word order evolution has been hypothesized to be constrained by a word order
permutation ring: transitions involving orders that are closer in the
permutation ring are more likely. The hypothesis can be seen as a particular
case of Kauffman's adjacent possible in word order evolution. Here we consider
the problem of the association of the six possible orders of S, V and O to
yield a couple of primary alternating orders as a window to word order
evolution. We evaluate the suitability of various competing hypotheses to
predict one member of the couple from the other with the help of information
theoretic model selection. Our ensemble of models includes a six-way model that
is based on the word order permutation ring (Kauffman's adjacent possible) and
another model based on the dual two-way of standard typology, that reduces word
order to basic orders preferences (e.g., a preference for SV over VS and
another for SO over OS). Our analysis indicates that the permutation ring
yields the best model when favoring parsimony strongly, providing support for
Kauffman's general view and a six-way typology.
