New Zealand offers an ideal setting in which to combine the study of evolution and biogeography - the distribution of living beings in space. The archipelago has been shaped by isolation from other landmasses since it split from Gondwana approximately 80 million years ago, followed by drastic flooding during the Oligocene, massive mountain building during the formation of the Southern Alps, and changing climate during the Last Glacial Maximum, all of which have left a signature on its biota. This research aims to study these historical processes while conducting a revision of a unique group of arachnids (order Opiliones - harvestmen or daddy long-legs) of ancient origin and that therefore have witnessed these geological changes through their evolutionary history. For this, the research team will combine classic taxonomic methods with cutting-edge molecular approaches to understand the diversity and evolutionary history of this under-studied group of arachnids. The research will also contribute to disseminating evolutionary research in islands through museum exhibits and broad initiatives and to train the next generation of evolutionary biologists able to combine genomics with biodiversity discovery and analysis. This will constitute the first comprehensive taxonomic treatment of an arachnid order in New Zealand, an area of unique species composition and a biodiversity hotspot for conservation priorities due to the degradation of many natural habitats. Postdoctoral researchers and and many students at three US institutions will receive extensive training and be heavily involved in the research effort.
This research will focus on the order Opiliones represented in New Zealand by 223 named species in five native families. Contemporary approaches to species discovery may revise this total number, which is already expected to increase by approximately 20%. With the large existing collections at the Museum of Comparative Zoology, and the availability of most types (original specimens used to describe and name species) in New Zealand museums, this research aims to tackle this fauna and study the evolutionary processes that shaped it at different time-scales and at an unprecedented level. A rigorous estimate of the Opiliones species diversity in New Zealand will be provided by using a combination of next-generation sequence data and cutting edge morphological techniques, serving as an example applicable to other regions of the world. The research will use transcriptomic data from 200 individuals to generate phylogenies of three southern Hemisphere lineages that will allow testing of biogeographic hypotheses related to paleo-endemism and ancient Gondwanan breakup events. Selected genera will then be used to test biogeographic hypotheses related to post-Gondwanan geological history, including Oligocene marine transgressions, Southern Alps orogeny and Last Glacial Maximum refugia, using a RAD-sequencing NGS approach. Finally the research aims to produce taxonomic monographs treating all the species of New Zealand Opiliones while developing new standards for linking biodiversity data, including images, videos, and genomic data, to specimen records through the centralized database MCZbase, publicly available online.
This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.