ABSTRACT
Explanation. Although survival of the fittest in nature does involve a lot of confrontation, competition, prédation, and other kinds of violent behavior, there is also a lot of peaceful cooperation, not only between individuals, but between species as well, for mutual benefit. Ecologists use the term mutualism when the partnership between unrelated species is so strong that neither partner can survive without the other. Mutualism very often develops between two organisms that have something that the other needs, so that forming a partnership is mutually beneficial. For example, there are numerous cases where animals and non-green plants, such as fungi and many bacteria, form mutualistic partnerships with green plants that provide food in return for the mineral nutrients or protection that the non-green organisms can provide.
