Ryan McGinley's metier is youth. The often smiling, and more often nude men and women cavorting in his photos are like jubilant animals, as untrammeled as their al fresco habitats. But McGinley's subjects are a far cry from Bruce Weber's Abercrombie Amazons and locker-room beefcake, and from the kitschy '70s nudist magazines the photographer cites as an influence. This series of photos culled from several cross-country road trips — McGinley's first West Coast solo show — evokes nothing so much as Thomas Eakins' later American pastorals, in which as much attention is paid to the surrounding landscapes as the bare-bottomed, sun-kissed sylphs who flit through them.