I. Bees and flowers: This is a very common example of mutualism. In this mutual relationship bees receive food i.e nectar and pollen where as the plants get benefited by dispersing their pollen. Flowers and bees have coevolved i.e. evolved together for millions of years.
2. Cichlid and fishes : Adaptive radiation/adaptive evolution
3. Flying squirrel and flying phalanger: it is an example of convergent evolution as they don't have recent common ancestor but still share many common characteristics.
It's a cell wall, common to some types of cells, like plant cells (one notable component of the cell wall is <span>cellulose, which is exactly where we obtain it from</span>).
