if you understand the general concept of evolution then the idea of not evolving may sound pretty bad to you (unless you’re playing pokemon).
to the general masses, ‘evolving’ is something we are constantly doing. all living things are constantly in competition with each other to best all comers for whatever food, light, water, or reproduction opportunity may present itself. apple too high in the tree? don’t worry, your genes will make your offspring taller! can’t afford to take a vacation? some day, we’ll have sprouted wings to fly wherever we want! dropped a pen and don’t want to pick it up? in just a couple hundred generations, we’ll be able to pick it up with our massive, prehensile wieners!
anybody who has taken an intro biology class, however, understands that evolution does not work like this. the uninformed assumption is that evolution occurs in order to better suit the organism to a certain task (ie – the giraffe’s neck grew long to reach the highest leaves on the tree). the truth is the exact opposite – evolution occurs when the limiting and challenging factors of an environment favor certain random traits in an organism (ie – the giraffe’s with shorter necks could not reach their food source as readily as those with longer necks and eventually died out). evolution is not so much an intelligent, intentional process of your genealogy responding to the outside world, but the outside world favoring those with the traits that most easily deal with its obstacles.
outside the human realm, evolution is a painfully slow process. it takes generations for these random mutations which change the course of a species’ existence to occur. however slow the process may be, there have still been some observable instances of speciation during the course of human history (and probably many more than what is referenced here).
humans have been recognizable human for over 130,000 years. there are studies which suggest that, despite this fact, we are indeed evolving at an incredible rate. this is most likely due to the fact that humankind, which began somewhere in africa, struggled through an ice age in a group of caves then spread outward rapidly to new and very different continents across the globe. as they reached new landscapes, climates, and ecosystems, their bodies were greeted with new challenges to overcome. stouter branches of the human genome, for instance, were better suited to the harsh winters and mountainous regions of europe than their more tropical counterparts. darker-skinned individuals dealt more easily with heavy doses of sunlight (but needed more of it in order to gain a sufficient amount of vitamin d) and therefore stayed near the equator in warm climates, and so on.
i was reading digg articles about a week ago and came across this. in the article, a study’s findings that those of african descent have a higher belly button, and therefore center of gravity, claims to explain the dominance of these people in footraces. since the center of gravity is higher, and the act of running is essentially a controlled fall where the legs both propel and stop downward motion, these people ‘fall’ at a much faster rate than caucasians can.
this makes perfect sense – humans who left the tropical climate of africa and ventured into the cold, white north faced fewer apex predators who could chase them down and eat them. in africa, however, where getting eaten by a goddamn cheetah is an everyday worry, the ability to run fast is a much more favorable trait.
all of this was a whole lot of words to get to my overall theory – though we may be evolving rather quickly as a species on our respective continents, the fact still stands that evolution only occurs in response to diverse, natural stimulae. today, we are increasingly homogenizing the world toward the western model.
as we approach this model globally, a model which removes nature from the equation as we alter landscapes into fields of wheat, corn, soy, etc., we are going to be removing the only thing which can legitimately move our species forward – exposure to the world which is rapidly changing around us. we’ve seen plenty of evidence that our way of life is not sustainable. when the reserves run out and the world has changed drastically around us, how can a species which has removed itself from the natural equation re enter and expect to survive?
some may respond to this by suggesting that reproductive selection will help – women favor men with big muscles. if only the strong survive, then clearly these strong men will easily deal with a post-western world. however, this is not so. first of all, the mass amounts of muscle deemed desirable in our society is completely unfeasible in the wild. shortly after going into nature, a man who eats 120 grams of protein a day to fuel his muscles through two-hour gym sessions will be hard pressed to find the same sort of controlled, isolated lifting and steady flow of nutrients his body needs to remain the same size. in nature, big is expensive and muscle men will quickly wilt down to a more manageable (albeit fit) size.
men and women both prefer a slender mate. those predisposed to fast metabolisms and slim figures, then, are selected for while the more stout individuals are selected against. any amount of fat in our society is deemed bad, and unless your abs are on full display, you’re a worthless slug with no hope of ever mating.
again, we’re wrong. these two studies (1 & 2) suggest that having a little extra flab can work as both insulation towards environmental and emotional stresses as well as generate life-giving hormones.
so, what have we learned today?
1. evolution does not happen in response to a need and never will – it’s more a dying-out of the unfit than a creation of the more-fit.
2. we have seen a lot of evolution in the human chain in the fossil record, due to massive exposure to new environments.
3. we live in a society which seeks to separate us from the natural world which could easily isolate our genes from being altered by a changing earth.
4. we’re doing very little in the way of making up for the lack of exposure to nature’s woes on our own.
i’m not saying we have to give up technology or stop advancing our culture. i’m merely saying, yet again, that fitness goes far beyond how you feel or look. fitness is a broad term which suggests an organism’s ability to survive when left to it’s own devices. as a culture, we foresee little ability to survive. we must make choices and efforts to better the fitness of ourselves and our communities if we wish to keep up with the world as a species- otherwise, we’ll be left far behind by evolution.