Date/Time
Date(s) - Fri 6 November
12:00 - 13:00
Abstract:
Microbial communities are highly responsive to environmental change and play fundamental roles in driving ecosystem functioning, this makes them powerful systems for understanding evolutionary and ecological processes. However, a focus on contemporary microbial dynamics means that very long-term processes can be challenging to study in a tractable way. In this seminar Dr William Pearman will outline how sediment cores can act as natural archives of these processes over decades to centuries. First, he will demonstrate how sediment core metagenomics can enable us to reconstruct historic microbial communities and their responses to different phases of human occupation of Aotearoa-New Zealand. Shifting from long-term processes in free-living systems, Dr Pearman will move to focusing on the freshwater zooplankton Daphnia. Sediment cores act as seed banks for Daphnia, preserving dormant resting eggs that can remain viable for decades. He will discuss our recent work that shows that key members of the Daphnia microbiome are vertically inherited and are consistently associated with resting eggs, suggesting these structures function not only as dispersal stages for their hosts but also as reservoirs of host-associated microbes. Finally, he will show how combining these microbial time capsules with resurrection ecology provides a unique opportunity to investigate how host-microbiome associations respond to environmental change and enable us to explore patterns of host-microbiome co-evolution across historical timescales.
Biography:
William Pearman is an inaugural Tawhia Te Mana Tūāpapa Fellow at the University of Auckland. His research combines population genomics and microbial ecology to better understand how hosts and their microbiomes interact over both short term ecological and long term evolutionary timescales. William has a long-standing interest in resolving methodological challenges so that techniques developed for model organisms can be applied to more recalcitrant ones. He completed his PhD at the University of Otago in 2023 in marine science studying how kelp biogeographic processes shape the kelp microbiome.