Most radiation on the UV spectrum is filtered by the atmosphere. Less than 5% of radiation with less than 300 nm reaches the ground. Also, UV radiation is muta

Most radiation on the UV spectrum is filtered by the atmosphere. Less than 5% of radiation with less than 300 nm reaches the ground. Also, UV radiation is mutagenic. > not enough to make evolutionary pressure At cellular level, plants and animals have several mechanisms to avoid and repair damage caused by UV radiation. Maybe the evolutionary pressure was to NOT see UV light!