It’s been shocking to watch news of the Brexit vote in Britain, Donald Trump’s promise to build a wall between Mexico and the U.S. and the ongoing threats and violence against ethnic minorities in many parts of the world. I’m not a political or social scientist, but my training as a biologist gives me some insight.
When I began my career as a scientist, geneticists were starting to analyze the molecular properties of single genes within a species. When we started looking at highly evolved species such as fruit flies, we thought we would find that their genes had been honed through selection over time, so they would be relatively homogeneous within single species. Examining one kind of protein controlled by a specific gene, we expected to find them all pretty much the same. Instead, we learned there was a great deal of heterogeneity, or diversity. A gene specifying a protein could exist in a number of different states.
This is now called “genetic polymorphism” and is considered to be the very measure of a species’ health. Inbreeding or reduction of a species to a small number reduces genetic polymorphism and exposes harmful genes, thereby rendering the species more susceptible to sudden change. In other words, genetic polymorphism confers resilience by providing greater possibilities as conditions shift.