Why is mutualism also known as co-evolution.

Explanation

In mutualism both the interactive species are benefitted. This system can also be safe guarded against cheaters.
In many species of fig tree, there is tight one two one relationship with pollinator species of wasp. The female wasp uses the fruit not only as oviposition site but also uses the developing seed within the fruit for nourishing its larvae. Plant also get pollinated. Thus, mutualism is known as coevolution.