In other places there must also be special indicators of summer, but in Durham, it is the annual opening of the American Dance Festival that marks the season. Through July, slender dancers of all ages and nationalities will appear like exotic flowers in the cityscape; the gaily-painted “dance buses” will ply between studios on Duke’s campus and the theaters, and a parade of great dance troupes will imprint audiences with their kinetic aesthetics. 2012 is the 79th year for the venerable festival (although not all of those have been in Durham), and the first with Jodee Nimerichter as director-on-her-own, following the retirement of long-time director Charles Reinhart last year. Nimerichter has chosen to begin with a frolic of laughs: tonight’s opening performance will be by Doug Elkins & Friends, who will reprise their take-off on The Sound of Music in the Durham Performing Arts Center (DPAC). Look for my review here tomorrow.