XVI International Botanical Congess

The biogeography of SE Asia and the W Pacific is complicated by the fact that these are regions on the border of two palaeocontinents that have been separated for a considerable period of time. Thus, two general patterns can be expected to occur: a pattern of Laurasian elements expanding into former Gondwanan areas (i.e. from SE Asia into Australia), and a reverse pattern for Gondwanan elements. On top of this, both elements occur in the Pacific, having arrived there as the Pacific plate moved westward, bringing the different islands within reach of SE Asia and Australia. In order to reconstruct the biotic history of these areas, two large data sets were generated, one for each pattern, which were analysed using cladistic methods. Because biotas consist of both plants and animals, which can be expected to have reacted to the same events, and because the number of suitable phylogenies available is limited, the data sets consist of both plant and animal groups.