Neogene marine ostracod diversity and faunal composition in Java, Indonesia: Indo-Australian Archipelago biodiversity hotspot and the Pliocene diversity jump

Abstract

Neogene diversity history in the world center of biodiversity known as the Indo-Australian Archipelago (IAA) or the Coral Triangle remains poorly understood. Of particular interest is the recently reported Pliocene diversity jump that is considered to have established the present-day biodiversity level of the region needs rigorous inspections. We investigated Neogene fossil marine ostracods from Java, Indonesia and evaluate and test the Pliocene Diversity Jump hypothesis. We found a significant diversity increase from the late Miocene to the Pliocene, supporting the hypothesis. At the same time, there are considerable differences in depositional environments between the Miocene and Pliocene samples. Although it is unlikely that the main reason of the diversity increase is due to this paleoenvironmental difference, further samples and data from the IAA hotspot region are needed for more rigorous inspections. Our comparison between species-level and genus-level data indicated that species-level data are better to detect detailed macroevolutionary diversity histories, and genus level data are more useful for paleoenvironmental and paleoceanographic reconstructions.