Why it evolved

To exploit a mutualistic relationship, the Cooperative Gulpfish has evolved bioluminescent lures on its fins, attracting smaller organisms that may offer services or become food. This adaptation is driven by the PRESSURE to form partnerships. The increased mouth size aids in consuming these attracted organisms. However, the reduced scale density makes it more vulnerable to predation by larger species like the Mud-Stalker and Famine Fins, and the increased metabolic cost of bioluminescence is offset by the energy-rich food sources attracted in the warm Tethys Shallows.