How should a dendrogram-based measure of functional diversity function? A rejoinder to Petchey and Gaston

Abstract

This paper is a response to Petchey and Gaston's criticism of our previous paper on the measurement of dendrogram-based functional diversity. In contrast to their suggestions, we insist that Euclidean distance is unsuitable to the analysis of variables with mixed scale types and maintain our earlier view that both the distance function and the clustering method can influence the dendrogram-based measure of functional diversity. We propose an extension of Gower's formula to accommodate nominal traits with non-exclusive categories and emphasize the necessity of the methodological standardization of functional diversity measures. © Oikos.