commensalism defines the coactions in which two or more species are associated and one species (commensal) at least, bencfits from the association while the other associate(s) is/ are neither benefited nor harmed. Example includes: lianas, which are vascular plant rooted in the ground but which climb up with the support of other trees and reach almost to the top of the forest canopy; epiphytes which grow on other plants for support and not for water or food supply.xamples of epiphytes include mosses, ferns etc.