Author: Andrea Corpolongo
Sunlight does not reach the deepest parts of the ocean, but life still thrives in the darkness. Below depths of 200 meters, where sunlight cannot reach, some organisms eat organic material that falls from the sunlit zone. For these organisms, photosynthetic organisms, such as phytoplankton and algae, form the basis of the food web. Other deep-sea organisms depend on a process called chemosynthesis, which is growth using energy from chemical reactions, rather than from the sun, as in photosynthesis.