home |  avr microcontroller & DIY electronics |  toolbox |  science club |  tuxtalk |  photos |  e-cards |  online-shop

### Doves and hawks

Imagine a world with only 2 kind of creatures: doves and hawks. Doves are very peaceful. When 2 doves meet they help each other and share their food. Not so with the hawks. They are very agressive. When a dove meets a hawk the dove hands over its food to the hawk as it doesn't want to fight. So it loses a little energy while the hawk wins some energy. However when a hawk meets a hawk a fight breaks out. You decide if the losing hawk lives on and how much energy he loses and how much energy the winning hawk receives. If enough energy is there a new animal is born and if an animal's energy level gets too low it dies. Play around with different values and see which animal wins as a species.

Of course in the real world no animal is as peaceful or as aggressive as the dove and hawk in this example. Each individual is a bit different and of course there are many other aspects e.g. availability of food, illnesses etc. that have a strong influence of the real outcome which is not in the model at all. Still I found it to be fascinating stuff to play around with the simulation as I got many results that were totally unexpected to me.

What percentages of doves:

energy start points:

energy needed for new animal to be born:

energy death level:

when dove meets dove energy +

when dove meets hawk energy:

hawk

dove

when hawk meets hawk :

energy plus for winning hawk

percentage of likelihood the other hawk will die

energy minus for losing hawk if he lives on

number of steps to calculate in one go:
ok start

References:
I first came across the description of the dove-hawk game in the book "Liars and Outliars" by Bruce Schneier (p. 28ff).
It was originally proposed by J. Maynard Smith and G.R. Price in their paper "The logic of Animal Conflict".
If you are interested in this topic you might want to start with wikipedia: https://en.wikipedia.org/wiki/Evolutionary_game_theory https://en.wikipedia.org/wiki/Evolutionary_game_theory