Upside down, hanging flower

These flowers hang upside down.  My own assumption, which is not supported by any knowledge of botany, is that this is an example of evolution in plant life.  These flowers grow in the cloud forest and rain forest highland areas of Costa Rica.  If these large bell shaped flowers grew right side up, they would fill will water many times heavier than their ability to remain upright.

This week we have photos of the Patagonia region of Argentina posted on our Viva la Voyage travel photo site.