Function for maximising rank correlation between environmental and compositional differences

As a follow-on from the post on scaling environmental variables before calculating distances, there is this function ('bioenv') in the vegan package which can be used to find the set of variables for which (scaled) environmental distances are the most rank-correlated with compositional dissimilarity. This could be useful for some analyses- i.e. if you want to know what environmental changes are the most important for turnover in the system.