How can injury or illness affect an animal's rank in a dominance hierarchy?

In the context of animal social behavior, a dominance hierarchy is a structured ranking system where individuals hold specific positions based on their ability to compete for resources and mates. While these hierarchies are generally stable, an individual’s rank is not necessarily permanent.1

When an animal is weakened by injury, disease, or senility, it typically experiences a decline in its social standing, moving downward in the hierarchy. This shift occurs because dominance is often maintained through the ability to win competitive interactions or successfully defend one's status against challengers. An animal that is physically compromised may no longer be able to bear the energetic costs of fighting or successfully defend its position against rivals, leading to a loss of status.123

Conversely, younger or subordinate individuals may wait for a dominant animal to become weakened by such factors before attempting to challenge them for a higher rank, as the risks of fighting a healthy, superior opponent often outweigh the potential benefits.3