Symmetry breaking in herding behavior

Asymmetric aggregation of animals under panic conditions has been observed in many species, including humans, mice, and ants. Theoretical models have demonstrated symmetry breaking similar to observations in empirical studies. For example when panicked individuals are confined to a room with two equal and equidistant exits, a majority will favor one exit while the minority will favor the other.

Possible mechanisms:

• Hamilton’s selfish herd theory
• byproduct of communication skill of social animal or runaway positive feedback
• neighbor copying

Escape panic characteristics

• individuals trying to move faster than normal
• individuals push; interactions become physical
• arching and clogging observed at exits
• escape slowed by fallen or dead individuals serving as obstacles
• tendency toward mass or copied behavior
• alternative or less used exits are overlooked