Outer bark variation

[QDurham]

>
>I don't know of any adaptations shown by bark.  Variation in bark character=
> is one of god's gifts to botanists.
>
>Eucalyptus trees show great variation within a locality: gums, boxes,=
> stringybarks, peppermints and iron-barks can all grow close together,=
> though they are different species of course.  Conversely, one type of bark=
> can be found in very different environments - again on different species.
>

These aren't adaptations?