Question

Substantiate with the help of one example that in an ecosystem mutualists 

tend to co-evolve and 

Answer 1

In nature, mutualists often co-evolve such as in Mediterranean orchid Ophrys. Ophrys employs sexual deceit to get pollinated by a species of bee. One petal of the flower resembles the female bee. If female bee changes its color pattern ever slightly the success of pollination will be reduced unless orchid flower co-evolves to maintain resemblance with the female bee.