DOCUMENTARY MINISERIES PREMIERE: Michael Pollan is the host of this four-part documentary series, which, like his book, is divided into four parts: “Fire, Water, Air, and earth. “We are the species who cooks, he begins. “No other species cooks.” All four parts are streamed beginning today, starting with the premiere, “Fire,” which includes a midpoint surprise appearance by James Taylor. Why? Ah, there’s the rub. Although, when discussing pigs in this documentary, the rub, and the ritualistic cooking, surfaces elsewhere.