Faunal evolution and patterns of endemism on Sulawesi, a geologically composite island

• Applicant: Dr. Alexander Riedel
• Subject Area: Systematics and Morphology (Zoology)
• Term: since 2020
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 439196708

The Indonesian island of Sulawesi is the product of well-documented terrane-amalgamation, comprising fragments of two separate continental plates plus an old volcanic arc. However, there is still much uncertainty concerning their subaerial (above-water) history and the extent of these areas over time. Both factors determine the development of autochthonous terrestrial biota, their in-situ diversification leaving a phylogenetic signature. The ancestral areas of less dispersive taxa can thus be assigned to specific geological terranes. We will study the evolution of two independent clades of wingless weevils having different life histories, and comprising more than150 species each. Expedition work will lead to the discovery of numerous undescribed endemic species and cover all relevant terranes adequately. We will use “genome skimming” to obtain mitochondrial genomes and nuclear tandem arrays of histones and ribosomal genes. These data will allow us to construct robust phylogenies. These will be time-calibrated and used for an ancestral area analysis comprising the geological terranes of Sulawesi and their source areas. We anticipate congruent patterns for our two model taxa. Their in-situ diversification will coincide or somewhat predate 23 Mya, the collision of the Sula spur of the Australian plate with the North Sulawesi volcanic arc. We will compare different geological scenarios with the timing suggested by our phylogenies. Areas with a longer above-sea history have probably accumulated more endemic biodiversity than areas emerged from the sea recently. A higher conservation value should be attributed to the former.

• DFG Programme: Research Grants