Even chickens form complex social relationships. Within a few days of socializing, chickens establish a stable social group with a clear hierarchy. In fact, we owe the expression “pecking order” to studies of the social relations among chickens by the Norwegian zoologist Thorleif Schjelderup-Ebbe, who found that pecking orders are ladderlike, with the top rung conferring great privilege in the form of food and safety, and the bottom rung fraught with vulnerability and risk.
