Shapes in Nature

I've always been drawn to the relationship between shapes and the environment and how they interact with, or relate to, each other.  It amazes me how such diametrically opposed shapes can work so well together.

Here are some examples of what I mean.

The softness of the clouds seem to match the curves of the rolling hills while the contrasting rough shapes of the chopped wood add a bit of tension, breaking up the scene's uniformity.  But it all seems to work.  This is nothing new to photography.  People have been composing images (paintings as well as photographs) like this for years.  From what I've noticed in many photo annuals (CA, PDN) there is a new resurgence of this style - minimalism that incorporates contrasting shapes.  It is actually everywhere, both in nature and man-made.

Here's another example.