Interrelationships Among the Liliatae: a Graph Theory Approach

Abstract

The interrelationships of the families of Liliatae were investigated by using a network generating program (NETS) which, unlike minimum spanning tree programs, considers both first and second nearest neighbours. Within the resultant network the distribution of families reflects many traditionally accepted assemblages, including the Zingiberales and Alismatales. The affinities of the Arecaceae in particular suggests that the observed similarities between some families may be due to evolutionary convergence rather than to a shared ancestry. This fact, plus the tendency of the network to branch rather than to form loops, helps to account for the difficulty in classifying the class.