Large scale biogeographic relationships in demosponge species assemblage in 3° by 3° grid cells from the Southern Ocean and neighbouring regions.

Each grid cell contains 3 or more species of demosponge. (a) Geographic representation of the relationships shown in c. (b) A simplified representation of the biogeographic relationships found in a. (c) Cluster analysis of the percentage faunal similarity between grid cells. The colours represent each geographic region: Antarctica (blue), South America (red), South Africa (purple), sub-Antarctic (yellow), New Zealand temperate (orange), New Zealand tropical (green), Southern Australia (dark pink), Tasmania (light blue), and SE Australia (light pink).