Giles Ross
Candidature
PhD Candidate
Thesis Title
Phylogeographic Analysis of Antarctic Soil Invertebrates
Research summary
Antarctica’s terrestrial ecosystems are populated by diverse yet understudied invertebrate communities, essential for healthy ecosystem functioning. My project aims to expand our knowledge of their distribution and response to environmental change. Mite, springtail and nematode samples collected from the islands off the Antarctic Peninsula along a 10º latitudinal transect will be analysed using comparative phylogeography to discern evolutionary histories of the endemic fauna. Contemporary distribution patterns are highly influenced by climatic changes that have occurred since the end of the Last Glacial Maximum (LGM) that led to melting ice-sheets and rising sea-levels. To determine the principle factors shaping soil invertebrate communities, temperate Australian ecosystems with similar dispersal limitations are compared with the Antarctic communities. Biogeographic events that enable dating of isolation periods can improve the timing of speciation events and generating dispersal models for specific invertebrate groups. By studying Antarctic fauna using a combination of approaches, I hope to reveal the fundamental drivers of their distribution at the a) local scale; environmental and biotic variables, b) regional scale; climatic influences and gene flow; and, c) temporal scale; evolution and dispersal. This project will contribute towards establishing baseline biodiversity for these vital ecosystem operators, and advance our ability to manage invertebrate biodiversity under accelerating environmental change.
Research images
3 x Oribatid mite morphotypes
Antarctic Peninsula sample sites
Invertebrate sample workflow from soil sampling to sequence analysis
Publications
Ross GM, Berg MP, Salmon S, Nielsen UN, (2022) 'Phylogenies of traits and functions in soil invertebrate assemblages', Austral Ecology, vol.47, no.3, pp 465-481
Ross GM, Horn S, Macdonald CA, Powell JR, Reynolds JK, Ryan MM, Cook JM, Nielsen UN, (2020) 'Metabarcoding mites: Three years of elevated CO2 has no effect on oribatid assemblages in a Eucalyptus woodland', Pedobiologia, vol.81-82, Article no.150667
Supervisors
A/Professor Uffe Nielsen, Dr Paul Rymer, Professor James Cook