Over time, they have evolved to be able sustain their population in changing and difficult environments. These adaptations have allowed earthworms to be an important and popular organism across the globe.
To begin with, one of the most important earthworm phenotypes is its bristles, which are integral in allowing the earthworm to move. These bristles are referred to as setae. The purpose of this phenotype is to provide traction for the worms to move freely through soil. This is quite advantageous as the worms are able to have greater mobility in their environment which allows which makes it easier for them to find food and travel. Another phenotype which proves advantageous for worms is their lack of a backbone or vertebrates leading to a streamlined body. They also do not have other body parts such as antennas or legs which also contribute to their flexible body structure. This allows the earthworm to move in narrow or tight spaces in the soil, which otherwise would be impossible with the body parts previously