For decades, Woods Hole Oceanographic Institution (WHOI) has studied the ways large marine predators (LMPs), like sharks, use the mesopelagic zone or middle layer of the ocean, better known as the ocean’s twilight zone (TZ). There could be reasons other than food that marine animals visit the twilight zone. Unlike other large filter-feeders (like the basking shark), the whale shark actively vacuums up water by rapidly opening and closing its mouth and expelling water through its gills. Sharks have adapted to the conditions and environment of the twilight zone, using anatomical structures and physiological characteristics to access this region to forage. He and his team study the ocean’s top predators and how they use the ocean’s twilight zone.