Palaeontology, biogeography and evolution of New Zealand insects

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Terrestrial ecosystems of the long-isolated landmass of New Zealand are modern biodiversity hotspots. Drastic tectonic and climatic events since the separation of New Zealand from Gondwana have resulted in the evolution of a unique insect fauna, which is distinguished from faunas elsewhere by high levels of endemism, gigantism and exceptional ecological interactions. Due to an extremely poor fossil record, the biotic consequences of environmental change over geological time-scales and the role of extinction and transoceanic dispersal in shaping the recent insect fauna are largely unknown. Newly discovered and exquisitely preserved insect faunas from lake sediments and amber offer for the first time the opportunity to reconstruct the palaeo-diversity and evolutionary history of New Zealand insects based on fossil evidence. The palaeo-ecosystems of these faunas are well known from previous studies, enabling the comparison of the diversity (on the order/family level) between the fossil faunas as well as with insects of modern New Zealand ecosystems. This project will investigate the systematics, taphonomy and diversity of fossil insects from four different palaeo-ecosystems: sparsely vegetated floodplains (Manuherikia Group), small volcanic lakes surrounded by Nothofagus/podocarp forest (Hindon Maar fossil Lagerstätte) or Lauraceae-dominated vine forest (Foulden Maar fossil Lagerstätte) and "amber forests" with araucarians (New Zealand amber). Reliably dated as Late-Oligocene to mid-Miocene, these newly recorded insect faunas are of special palaeontological importance as they occur shortly after near-complete marine inundation and reduction of terrestrial diversity in the Oligocene and prior to habitat modifications in the course of mountain building (Southern Alps) and post-Miocene climate cooling. Including selected taxa of the studied insect faunas as fossil calibration points in phylogenetic chronograms will refine the timing of diversification of relevant groups and enable testing of current biogeographical hypotheses.