Our Director of Artistic Administration Eric Mathis, who also plays trombone with the orchestra, has the answer for this one!
Often at the end of a piece, the conductor will single out one or more individual musicians to stand and accept the audience’s applause. At times, it will be really obvious that at some point in the piece the individual performed an important solo, but sometimes the conductor might want to acknowledge a musician who didn’t necessarily have a solo, but still had a particularly demanding individual part that they performed exceptionally well. Often, part of an orchestral musician’s challenge is to play a difficult part while NOT standing out from the crowd! In other cases, the conductor might indicate for a full section to stand for a “solo bow” when they performed a challenging work really well as a unit.