Oceanography SeminarFebruary 14, 3:00pm - 4:15pm
Mānoa Campus, MSB 100
Hawai'i Institute of Marine Biology
University of Hawai'i
"Comparative Evolutionary Ecology and Next-Generation Genomics Reveal Patterns of Selection in Deep Sea Urchins and Over-heated Reef Corals"
Abstract: Recent advances in nucleic acid sequencing have brought the full power of genomic analysis into "non-model" systems, and thereby have empowered evolutionary biologists to deeply query systems that pose fundamentally interesting questions about the process of adaptation. In this seminar I will focus on two such systems: first, closely related shallow and deep-sea urchins, and second, reef corals living near their critical thermal thresholds.
First, we compare three Strongylocentrotid urchins, one of which has recently diverged from the ancestral habit of a shallow-water lifestyle, and adapted to survive in the deep sea (~1000 m). Here we ask if adaptation to a novel habitat can leave patterns discernable at the whole-genome scale. We compare thousands of genes across these species (9,258 - 14,543 genes) that differ in stage and tissue-specific expression, and we examine patterns of purifying & positive selection as indicated by patterns of substitution in protein-coding regions. By using traditional non-synonymous/synonymous substitution indices (dN/dS) as well as a maximum likelihood branch-specific model (HYPHY), we show that all species show predictable differences in tissue/stage specific selective constraint, but the recent deep-sea invader shows elevated rates of adaptive evolution. These elevated rates are particularly high in genes associated with biomineralization, a function challenged by the low carbonate saturation environment of the deep sea.
Second, we will explore an on-going research program investigating thermally tolerant reef corals in American Samoa. Here we will first cover spatial patterns of thermally resistant coral symbionts both locally in a back-reef pool system and across the Indo-Pacific. Then we will turn to experimental evidence of elevated thermal tolerance associated with both hosting such symbionts, and acclimatization to high-temperature habitats. Finally we will turn to whole-transcriptome expression data highlighting the apparent mechanism behind this acclimatization - front-loading of stress mitigating genes.
Oceanography, Mānoa Campus
Thursday, February 14
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Condom Fair 2013Mānoa Campus, Campus Center
Pacific Connections Seminar SeriesMānoa Campus, 3121/3125 John Burns Hall (East-West Center)
The Making of The Glades ProjectMānoa Campus, 325 Henke Hall
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One Billion Rising at UHMMānoa Campus, Campus Center, 2500 Campus Road
Political Science Final OralMānoa Campus, Saunders 624
Stephen Wilcox, baritoneMānoa Campus, Orvis Auditorium
Oceanography SeminarMānoa Campus, MSB 100
Chess Club at UH Manoa MeetingMānoa Campus, Campus Center Room 310