Pecking order

Pecking order is a system of organization among a flock of poultry. In this system, a bird pecks another bird who is of lower rank, and submits to pecking from a bird of higher rank.

The basic concept behind the establishment of the pecking order among, for example, chickens, is that it is necessary to determine who is the 'top chicken,' the 'bottom chicken' and where all the rest fit in between. Consequently, this also determines which chicken gets to eat first or which chicken gets to peck on any other chickens they want. The top chicken is one which can peck any chicken it wants. The bottom chicken is one that lets all the other chickens peck on it and stands up to none. There are chickens in the middle, who peck on certain chickens but are, in turn, pecked on by other chickens higher up on the scale.

It is a basic psychological concept that has its counterpart in other animal species as well, including humans. Among mammals and other animals, the term "dominance hierarchy" is used.