The perks of being a variant

    Most generally, I honestly feel as though genetic variation is a happy chance of nature. In a sense, mutation is kind of always an accident that is arguably taken advantage of by cell-regulation proteins, so to me that makes most of evolution a bit of an accident (that then makes the most of itself.) On the opposite side of the coin, though, variation also naturally serves as a buffer against selective forces: plants with variable genetics are protected from blights, same goes for animals and parasites, coat/skin color variation aids for camouflage in novel territory, etc. Variation serves to give populations, not necessarily individuals, more opportunity for survival.

    Pragmatically speaking, variation isn't cut out of the equation due to the chance of evolutionary mechanisms. Mutations don't just stop happening when a species is adapted to its environment. Gene flow brings in genetics from disparate infraspecific populations that provide variation that hasn't resulted from a population's own gene pool. Selection being blind to unexpressed recessive alleles in homozygotes allows for the potential for homozygous recessives of Mendelian traits to always have a chance for increasing in frequency if for some reason that phenotype becomes beneficial. Normal distribution of quantitative traits allows for similar genotypes to have a wider range of possibility in their expression within a population, subtle differences that can potentially lend great advantages to their fitness. Even something as basic as random assortment of genes during sexual reproduction allows for variation to be maintained. Even if on an empirical level, variation is governed by collections of chance events, it's almost as if they purposefully work together to make sure that no specific threat can wipe out populations singlehandedly, to ensure life's ability to continue past catastrophes.