The white sand belt of western Madagascar: Evolution in a neglected ecosystem.

• Applicant: Professor Dr. Miguel Vences, since 12/2024
• Subject Area: Ecology and Biodiversity of Animals and Ecosystems, Organismic Interactions ; Evolution, Anthropology ; Systematics and Morphology (Zoology)
• Term: since 2022
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 507825896

Madagascar's extraordinary species richness and endemism is reflected by the presence of various main biomes on the island. One highly distinct ecosystem that has received very little attention, and indeed has not usually been recognized as such, is a system of patches of almost pure white sand (WS), forming both a system of coastal dunes and an enigmatic inland corridor, spanning in a north-south direction in arid western Madagascar. This WS corridor is known to host numerous highly specialized, microendemic animal and plant species but only very few parts of it have been subject of biological exploration and inventory. The project proposed here takes for the first time a holistic, hypothesis-driven view at the biota colonizing Madagascar's WS ecosystem. It will combine (i) a comprehensive diversity assessment for various groups of psammophilous organisms (squamates, arthropods and plants) across the inland and coastal WS corridors by DNA barcoding and environmental DNA analysis, with (ii) in-depth assessment of genetic divergence, phylogeny, phylogeography and demography of selected taxa in the more accessible north-western sub-section of the WS ecosystem, using a genomic (RADseq) approach, and (iii) pilot sedimentological assessments. The data will be used to test temporal and mechanistic hypotheses of the origin and fragmentation of the WS ecosystem (e.g., Middle Miocene paleo-littoral vs. Pleistocene rapid climate oscillations), tempo and pattern of adaptation to this unique environment (e.g., reduction of limbs and eyes in hyper-specialized squamates), besides methodological innovations to reduce detection bias in elusive fossorial species.

• DFG Programme: Research Grants
• Ehemaliger Antragsteller: Dr. Aurélien Miralles, until 12/2024