Do Pigs Know Game Theory?
We as humans can learn from our past behavior and usually judge the outcome of an action before we perform it. In order to judge outcomes better and to achieve more optimal outcomes certain people have developed rules and methods. These include the methods for finding the Nash Equilibrium among other things. When given a diagram like this one 
we can assign scores to the potential outcomes and find the optimal one. But can an animal that doesn’t have the same capacity for thought that we do also find the optimal outcome and put in motion the optimal action? In 1979 two scientists set out to research whether pigs trained to press a lever or a button for food could achieve a Nash Equilibrium in which both pigs get to eat. To test this, they researchers compared the actual actions of the pigs to what they calculated to be the Nassh Equilibrium.
In this experiment there were two pigs in a pen, one dominant, one subordinate. There was a panel which the pigs were trained to press, that when pressed drops food. If the dominant pig pressed the panel, it had to run across the pen and would get around 30% of the food dropped, with the rest going to the other pig. If the subordinate pig pressed it, it would get no food, and the dominant pig would get all of the food. If neither pressed it, neither would get food. After a few runs, the pigs learned how to get the most food possible, which is the situation in which the dominant pig presses the panel. So in other words the pigs were able to determine the Nash Equilibrium for this scenario.
Link to article referenced: http://mindyourdecisions.com/blog/2016/09/06/pigs-know-game-theory-and-how-strength-can-be-a-weakness-game-theory-tuesdays/
Link to study referenced in article: https://www.researchgate.net/publication/256111949_Social_behaviour_in_pigs_studied_by_means_of_operant_conditioning