What is co-evolution?

Explanation

The interaction between organisms, when continues for generations, involves reciprocal changes in genetic and morphological characters of both organisms. This type of evolution is called co-evolution. It is a kind of co-adaptation and mutual change among interactive species.
Examples:
(i) Corolla length and proboscis length of butterflies and moths (Habenaria and Moth).
(ii) Bird's beak shape and flower shape and size.
More examples: Horn bills and birds of Scrub jungles, Slit size of pollinia of Apocynaceae members and leg size of insects. It is an inter specific interaction.