Plants (But are there any?)
Actually, plants are not able to grow in the twilight zone. As you probably know, sunlight is a vital ingredient needed in the process of growing a plant. Unfortunately, there is very little sunlight penetrating through to the twilight zone, so plants are not able to grow down there. Therefore, photosynthesis cannot occur either. Photosynthesis is the process by which plants use the sunlight to make their own food. Creatures that live in the twilight zone also have to adapt to living without much sunlight, but they are mostly bioluminescent creatures, so it is possible for them to live.