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Figure 3. A scientist playing with kinetic sand that makes a dynamic seafloor map. As the sand is piled and dug into, it uses color to create a representation of a topographic map in real time.
midwater zone of entire ocean basins. Each night, these ani- mals migrate hundreds of meters upward to hunt for food under the cover of darkness. This active conveyer belt of life plays an important role in the carbon pump that regulates the climate, and the animals serve as a critical food resources for many of the fish, including tuna and salmon, that end up on your dinner plate as well as for seabirds, seals, whales, and dolphins. Despite the large number of animals in these midwater layers, currently estimated at 10 billion tons, the mesopelagic zone is among the least investigated components of the open ocean ecosystem, largely due to the challenges of working in this deep, dark alien world. My colleagues and I developed a new approach, integrating traditional ship- based echosounders into a deep-diving autonomous vehicle that could take us into the layers to give us a fish eye or ear view (Moline et al., 2015). This allowed us to observe how animals were organized in midwater and, ultimately, to use sound to understand how predators find and use midwater resources while the mesopelagic zone animals avoid being
eaten. We learned that animals form groups to hide in open water (Benoit-Bird et al., 2017). This strategy is key to their survival but will also have large impacts on how impending fishing pressures impact the ecosystem. Through work like this, we are developing a better understanding of how ani- mals and humans may compete for fish in the ocean in order to guide sustainable management.
To tell our story, the exhibit team developed a pod of sorts that welcomes the visitor with a model of our bright yellow underwater robot. On a scrim screen below the robot, a short video narrated by me explains the problem, how we came to a technical solution, the challenges we faced in the process, and the importance of the results. Dots rep- resenting animals rearrange themselves on the screen to show how our data has changed the view of organization in midwater as the back wall of the installation glows brightly, immersing you in our pointillist view of the mesopelagic zone (Figure 4). I was overwhelmed at seeing my research come to life in this multidimensional form. Experiencing my data in a way reminiscent of Tom Cruise’s character in Minority Report interacting with complex information was remarkable and perspective altering. Thinking in four dimensions in a featureless environment is always a chal- lenge for us terrestrial mammals as we venture into the ocean to understand its mysteries and, for just a second, I
Figure 4. The installation lights up with dots that represent animals measured in our data, dynamically illustrating how our view of the organization of animals in the mesopelagic zone has been dramatically changed through measurements with new technologies, including the autonomous underwater vehicle represented by the model.
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