Game Theory in Biological Evolution
Source: https://www.theguardian.com/science/2014/jun/20/game-theory-life-qanta-magazine
In class, we have seen that any strategic interaction between several decision makers can be analyzed using Nash equilibriums. Now researchers from Berkeley have examined biological evolution through the lens of game theory and found that natural selection can be viewed as a repeated game where genes are the players and each gene has a number of strategies in form of genetic variations, or alleles. For instance, an allele might make an organism more suitable to survive in colder climates.
Each gene plays a mixed strategy with some weight assigned to each allele. The game is played over and over again and at the end of each round, the gene, or player, evaluate how well each of its alleles performed in the current genetic pool and then increase the weight of good alleles while decreasing it for the bad ones.
This continues on, and a situation close to a mixed Nash equilibrium is attained in the long term which results in the creation of a highly fit population, which in this case is the modern makeup of nature with humans as the best fit population. The researchers also found an interesting result that evolution values both fitness and diversity. This sheds light on a long-standing paradox in population biology that the fittest organisms don’t always wipe out their weaker competition. They compared this to a situation in the financial world, where you might be tempted to place all your money on a soaring stock. But if circumstances change and that stock starts to tank, you’re better off having invested in a more balanced selection. Hence, an organism’s genes may be the perfect fit for a particular environment, but if some conditions change, then a genetically diverse population is more likely to survive.
Through some experts remain skeptical about the findings and their usefulness in affecting our understanding of evolution, it does indeed present a novel and interesting viewpoint of evolution in terms of game theory.