So what is 'proof'? We have to remember that on the ground these are nothing but a series of open water wet spots in a marsh, and appear to have no meaning. But from the air they make a pattern of an unmistakable message. Surely salt marshes are alive and growing, and the width of these lines narrows as plants expand; but even with what is left, this is a spectacular site. Also, rising sea levels may have overtaken and obscured many sections of the 'message' but THIS IS NOT NATURAL.