Dutch engineer Theo Jansen builds complex walking sculptures from PVC pipe and turns them loose on the beaches of the Netherlands, where they have been evolving (with his help) for 20 years.

“Over time,” he says, “these skeletons have become increasingly better at surviving the elements such as storms and water, and eventually I want to put these animals out in herds on the beaches, so they will live their own lives.”

“I’ve seen a lot of mechanical sculpture, and Jansen’s animari are the finest I’ve seen by far in the ‘low-tech clockwork’ mechanism category,” robotic designer Carl Pisaturo told Wired in 2005. “These are amazing creations, and the simplicity of the technology and the fact that they are wind-powered only makes their poetic motions more impressive.”