If you watch backyard birds for even a few minutes, you will likely see some characteristic behaviors.
One example is "foraging" styles – the behaviors a given type of bird uses to find its food. Some types of birds, such as sparrows, are famous for their "double-scratch" behavior. This is a maneuver in which the sparrow jumps forward and back, quite quickly...twice.
In each forward jump, the bird lightly hooks leaf litter with its toes. Each return jump pulls the litter aside, exposing, perhaps, seeds underneath. Other species of birds, however, like robins, might be too big to pull off this sleight-of-foot and instead use their bill to simply grab any leaf litter and toss it aside. Two strategies, one goal: expose and grab that food!