Over vast expanses of time, powerful tectonic forces have massaged the western edge of the continent, smashing together a seemingly endless number of islands to produce what we now know as North America and the Pacific Northwest. Intuition tells us that the earth’s crust is a permanent, fixed outer shell – terra firma. Aside from the rare event of an earthquake or the eruption of Mount St. Helen’s, our world seems unchanging, the landscape constant. In fact, it has been on the move for billions of years and continues to shift each day.

Co-ordination of flight requires tremendous brainpower, and co-ordination of active flight, with the constant shift in the shape and location of massive wings, even more so. Nature is extremely parsimonious, not frittering away investment in any organ where it is not needed.