Typically performed by sorority sisters immediately prior to a picture where one or more participants slightly bend their knees and lean on their calves with their arms regardless of whether or not people are behind them in the photo. Possibly used to accentuate the butt. Although scientists have still yet not found the origin or purpose of this tribal ritual, much discussion has been devoted to it's research.
"seriously, Becky is always bent over in all her pictures. You'd think she has scoliosis or something. I guess all those sorority squat pictures add up."