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Andrew Thurber did his undergraduate work at Hawaii Pacific University where he received a Bachelor’s of Science in Marine Biology and minored in Mathematics.  During this time he worked at University of Hawaii, Manoa under the guidance of Dr. Craig Smith who introduced him to deep-sea infauna and invertebrate biology – two foci of his research ever since. He then went to Moss Landing Marine Laboratories, where he received a Master’s of Science in Marine Science by studying the role of the pelagic microbial loop in the diet of Antarctic sponges.  He completed his PhD at Scripps Institution of Oceanography where he studied deep-sea reducing ecosystems in the lab of Dr. Lisa Levin.  He is now a researcher at Florida International University where he will continue to pursue his studies of the interactions between soft-sediment metazoan and microbial assemblages and the impact this has on biogeochemical cycling and ecosystem function.

ABSTRACT:

Bacteria and Archaea are often ignored or treated as a single “microbial box” in metazoan food-web studies.  With our new found understanding of how Bacteria and Archaea impact global biogeochemical cycling, the differential role of divergent microbial metabolisms and lineages in food webs must be addressed. Deep-sea methane seeps provide a model habitat to study these cross-domain trophic interactions due to their high density of Bacteria, Archaea and Metazoans. During the discovery of New Zealand’s methane seeps, an unexpectedly dense habitat of heterotrophic infauna, dominated by ampharetid polychaetes, was found to co-occur with incredibly high methane emission.  Through mass-balance calculations, based on isotopic mixing models and fatty-acid analysis, we were able to identify that aerobic methanotrophic bacterial biomass fuels this community.  This is in sharp contrast to the current paradigm of archaeal methane oxidation being the dominant sink of methane in marine sediments. We hypothesize that top-down forcing, exerted by this metazoan fauna, shifts the dominant domain responsible for methane oxidation off New Zealand’s coast leading to increased emission of a green house gas.

In addition to unique heterotrophic relationships, novel symbiotic relationships are often discovered during exploration of deep-sea habitats.  A charismatic example of this was a recent discovery of the second species of Yeti crab, a species which waves its bacteria-laden claws (chelipeds) in methane-seep fluid.  We show through molecular, behavioral, and morphological analysis that this species farms its chemosynthetic bacteria in a novel form of symbiosis.