Double helix stairs
Taken on Treasure Island in the San Francisco Bay of California, this image titled “Double helix stairs” by photographer Jef Poskanser is composed of strong sun on a man-made spiral access stairway paired with its natural shadow on the wall of a nondescript tank.
Our banner is a remix of this image found using the search term “double helix” over at Google Images. A second page search result yielded an image file named Double helix over at Wikimedia Commons.
Originally posted in a Flickr photostream on October 20, 2006, the file was was transferred to Commons in the Category: Spiral stairs on March 25, 2008 and graciously released into the public domain through Creative Commons Attribution 2.0 Generic.
Here, perhaps, is visual evidence, that both man-made and natural elements can mimic each other.