Animals inhabiting the darkness of caves are generally blind and de-pigmented, regardless of the phylum they belong to. The eyes are also well-adapted for use under very low light. This is due to both genetic drift (neutral hypothesis) and direct and indirect selection (selective hypothesis) occurred together during the loss of eyes in cave animals like lions cubs(Rétaux). Solution Animals inhabiting the darkness of caves are generally blind and de-pigmented, regardless of the phylum they belong to. The eyes are also well-adapted for use under very low light. This is due to both genetic drift (neutral hypothesis) and direct and indirect selection (selective hypothesis) occurred together during the loss of eyes in cave animals like lions cubs(Rétaux)..