Twenty-five years ago, artist Theo Jansen built a new life-form. Made of PVC pipes and zip ties, his strandbeest (Dutch for "beach beast") walked along a beach under wind propulsion. Since then, Jansen has created many more beests and inspired a small army of imitators. "The perfect strandbeest is a specimen that lives on its own," he says, "so I don't have to think about it anymore." Some of his strandbeests, and other makers' so-called hackbeests (see the image gallery below), will begin their first-ever tour of U.S. museums this fall. They will be on view at their first stop, Salem's Peabody Essex Museum, through January.