Are plant adaptations to growing on serpentine soil rare or common? A few case studies from New Caledonia

The relative commonness of a shift in soil preference (from non serpentine to serpentine soils and vice versa) in the New Caledonian flora is examined. A number of phanerogam genera occurring on the island of which modern phylogenies are available are used in this study (Acianthus, Cupaniopsis, Guioa, Morinda and in particular Oxera). It is concluded that the ability to grown on serpentine soil is either a plesiomorphic or a very homoplasious character for most groups in this study and that therefore the hypothesis that serpentine soils preserve the indigenous flora against competition with immigrant species can not be supported for these groups.