What is the term used to describe an environment with low light levels?

The term that describes an environment with low light levels is scotopic. Scotopic vision refers to the capabilities of the retina under low-light conditions, where rod cells in the retina are primarily responsible for vision. This is distinct from photopic vision, which occurs in well-lit conditions and relies on cone cells.

In scotopic conditions, the ability to perceive shapes and movement is enhanced, while color perception diminishes since rods are not sensitive to wavelength differences like cones. This makes scotopic vision crucial for animals, including many nocturnal species, that are active during the night and must rely on their ability to see in dim settings.

The other terms, such as photopic and mesopic, refer to conditions of bright light and intermediate light conditions, respectively. Nyctopic is not commonly recognized in scientific literature to describe light levels and is thus not applicable here. Therefore, scotopic is the most accurate term to describe environments with minimal illumination.