California performance artist Bonnie Ora Sherk built a career out of inserting herself, quietly and deliberately, into everyday life. A recent survey of her early work returns to the performances that made her reputation in the 1970s, when she treated the city itself as a stage and the boundary between art and ordinary behaviour as something to be tested rather than observed.

The best-known of those works is Sitting Still, a 1970 series in which Sherk placed herself in ordinary chairs in unremarkable San Francisco locations, from a flooded building site to the Financial District and the Golden Gate Bridge. Dressed formally, she sat for about an hour at a time, changing the atmosphere of a place simply by being unexpectedly present in it, while drivers and pedestrians became an accidental audience.

The series reached its most startling point with Public Lunch in 1971, when Sherk ate an elaborately catered meal inside an empty cage at the San Francisco Zoo's Lion House, next to big cats in a neighbouring enclosure, during public feeding time. Visitors watched both the artist and the animals pace, nap, and eat, a doubling that collapsed the distinction between spectator and spectacle and asked who, exactly, was on display.

Sherk went on to develop that interest in shared space through Portable Parks, pop-up green spaces installed above highway overpasses and in downtown alleyways, and through Crossroads Community, also known as The Farm, which she ran from 1974 to 1980 as a place for urban farming, animal husbandry, and experimental performance. Together, the works present an artist who treated ecology, community, and performance as a single practice, decades before those concerns became common currency in contemporary art.