Exploring life in the deep sea earns top dissertation award
Gabrielle Ellis
Groundbreaking research uncovering life in one of Earth’s most mysterious environments—the deep sea—has earned Gabrielle Ellis, a University of Hawaiʻi at Mānoa graduate, the 2024–25 Dr. Clifford K. Mirikitani, MD, JD & John M. Mirikitani, JD, PhD Outstanding Dissertation Award from the UH Mānoa Graduate Division.
Ellis, who earned her PhD from the Department of Oceanography, focused her research on tiny deep-sea animals living more than two miles below the ocean surface in the Clarion-Clipperton Zone, a vast area between Hawaiʻi and Mexico. The region holds valuable mineral deposits important for renewable energy, but is also home to fragile and little-known marine life.
Her dissertation looked at how deep-sea communities change over time and across different habitats, from the smallest larvae to adult animals. By studying thousands of samples, Ellis created one of the most complete pictures so far of deep-sea biodiversity in an untouched environment.
“The award of the Mirikitani Outstanding Dissertation Award is an absolute honor both for me as an emerging scientist, as well as for the recognition of deep-sea ecology as a field,” Ellis said. “Despite increased attention to the deep sea emerging with discussions around deep-sea mining, more than 99.9% of the deep-sea is unexplored, and so many foundational questions are unaddressed. Working in the deep sea is inherently collaborative; we work on ships in the middle of the ocean for long periods of time and often rely on each other for ideas, data and support. As such, credit is also due to my collaborators, including my labmates and advisors, who have really inspired me throughout the years and are absolutely instrumental in the success of my research.”
Her findings include one of the largest collections of deep-sea larvae ever gathered and some of the first detailed information about how these species grow and survive. The work helps scientists and policymakers better understand how deep-sea mining and climate change could affect ocean ecosystems and what steps can be taken to protect them.
- Related story: Rare glimpse at understudied ecosystem prompts caution on deep-sea mining, October 1, 2025
Ellis is now teaching environmental science at Georgetown University, continuing her mission to share the importance of ocean research and inspire the next generation of scientists.
The Mirikitani Outstanding Dissertation Award is given each year to one UH Mānoa PhD student whose dissertation demonstrates exceptional originality, significance and scholarly achievement.
The Department of Oceanography is housed in UH Mānoa’s School of Ocean and Earth Science and Technology.
Read also on UH News.