They say everybody needs a hobby, and for the past six months, mine has been taking videos and photographs of slime molds in the oak and redwood forests near my home in California. Perhaps we’ve met somewhere on the trail? I was the guy on the ground with a lens clipped to his iPhone, the patient wife, the children asking worriedly from a distance whether a plant was poison oak. Perhaps you may have recognized my “slime-molding outfit”: the frayed Y2K jacket and Old Navy cargo pants caked with mud of many vintages. Perhaps, if you dared ask what I was doing, I popped up and (in those days when strangers stood close to one