Two animals want the same resource. Play Hawk (fight for it) or Dove (back off). Two Hawks fight and both get hurt; two Doves share peacefully; a Hawk vs a Dove means the Hawk takes it all.
Round 1: Fight or back down?
No contests yet. Choose your move! 👆
Resource is worth 6, a fight costs 8.
In nature, a whole population plays this game repeatedly. Click "Run Generation" to simulate how the percentage of Hawks in the population changes over time, based on which strategy earns more points on average.
With Resource = 6 and Fight Cost = 8, the theoretical Evolutionarily Stable Strategy is about 75% Hawks. Keep clicking "Run Generation" and watch the bar settle near that number, no matter where it starts!
Generations simulated: 0
The Hawk-Dove game (also called Chicken in some contexts) was developed by biologists to explain why animals don't always fight to the death over resources like food, territory, or mates. In the model, "Hawk" strategies always escalate to a fight, while "Dove" strategies always retreat rather than risk injury. When two Hawks meet, they fight and pay a steep cost — sometimes both come away worse off than if they had just shared. When two Doves meet, they peacefully split the resource. When a Hawk meets a Dove, the Dove wisely backs off and the Hawk gets everything.
At first glance, being a Hawk seems like the winning strategy since Hawks always beat Doves head-to-head. But if every animal in a population became a Hawk, they would constantly fight each other, and the costs of injury would outweigh any gains. In that world, a rare Dove would actually do better by avoiding all those costly fights! This tension pulls populations toward a stable balance — a mix of Hawks and Doves (or individuals who sometimes act like a Hawk and sometimes like a Dove) where neither pure strategy can invade and take over completely. Biologists call this balance point an Evolutionarily Stable Strategy, or ESS.
This idea, pioneered by biologist John Maynard Smith, transformed how scientists think about animal behavior and aggression, showing that nature often settles into equilibrium mixes rather than everyone adopting the single "best" strategy. The same logic shows up whenever aggressive and cautious approaches compete for the same resource, including in many human situations.
Split a group into pairs and give each pair a "resource" (a card, a point, or a piece of candy). Each round, players secretly choose Hawk or Dove using hand signals (fist = Hawk, open palm = Dove), then reveal together and score using the payoff matrix above. After several rounds, count how many people played Hawk vs Dove and discuss whether the group naturally settled into a stable mix, just like the population simulator above.
What is the Hawk-Dove game?
It's a model of conflict where "Hawks" always fight for a resource and "Doves" always back down. Two Hawks meeting causes a costly fight, while two Doves share peacefully.
Why don't all animals just become Hawks?
If everyone is a Hawk, constant fighting is so costly that a rare Dove actually does better by avoiding fights, pulling the population back toward a mix of both.
What is an Evolutionarily Stable Strategy?
It's a strategy (or mix of strategies) that, once common in a population, can't be beaten by any rare alternative strategy trying to invade.
Does the Hawk-Dove game apply to humans?
Yes — it models many human situations involving costly conflict versus peaceful sharing, from playground disputes to business competition to international relations.