Our bodies undergo a tremendous amount of change throughout our life. Music heard in adulthood is never quite as good as that discovered in youth and food never matches the love and comfort of a parent or grandparent’s particular method for combining the ingredients of your favourite dish. Yet the speed with which change occurs is, barring certain blunt injuries, mind-numbingly slow. Such is the case that one, observing from the perspective of one human lifetime, could be forgiven for concluding that nothing much really changes. What we fail to notice is that our entire aural apparatus, from the ear to neural interpretations of the inner ear bone vibrations in the cerebrum, changes dramatically throughout our life. Ditto our tastebuds, which die and are reborn with micro changes that medical science has not yet conclusively put the lid on. We could chalk this up to normal wear and tear, a phenomenon constantly occurring in our bodies, but that it takes the ownership of property or a vehicle for some of us to truly understand and appreciate. The point is these small changes can eventually lead to major shifts, spanning the whole species.
These major shifts will result in the evolution of a given species if selected from generation to generation. For humans, from our perspective, evolution is also a relatively snail-paced process. And to see this phenomenon in humans requires the consultation of the fossil record. But fortunately, in smaller organisms, we can observe these changes.
In the UK, an all too familiar textbook example of natural selection giving way to evolution is found in the Peppered Moth. Sometimes called Darwin’s Moth, one might say the normal peppered moth bears a relatively even pattern of black and white splotches to its hue. That is until the mid-nineteenth century turned Manchester into a smoggy cloud of industrial might. In these dark and dismal times, the peppered moth stood out to its predatory neighbour flycatchers, nuthatches, and European robins, so something needed to change. Peppered moths selected for a higher concentration of dark pigment, allowing them to blend into the Industrial Revolution. To add a cherry on top, after the UK (sort of) got its act together and started regulating its carbon footprint, we witnessed a change back to the familiar peppered moth pigmentation from the good old days. There and back again, the whole process only took 150–200 years. In just over the last year, we have seen evolution on the microscopic level as variants of the Covid-19 virus select their way through our natural immune defences. Thanks to our less than Three Musketeers approach to global vaccination we are filling textbooks with examples that maybe one day a future generation might learn from.
Currently, we are experiencing an unprecedented level of acceleration in numerous systems, so it begs the question as to how humans will change. Since humans have only been a feature on Earth for a relatively minuscule fraction of time it can be difficult to properly study the changes we have undergone since the first Homo sapiens walked the earth. But perhaps we need not consult the fossil record (which humans and other primates, at the moment, have not contributed a great deal to) but look within ourselves to see the change that is always with us – for you see, evolution is slow, but is abysmal at covering its tracks!
On many of us, but importantly not all of us, there are parts that tend not to serve a particular purpose, often they are dormant or reduced parts that served a function in our ancestors. We call these vestigial organs. A classic and often dubious example of a vestigial organ is the appendix, that worm like projection that presents at the junction of the small and large intestine. You can locate yours either by the scar where it had been removed in the past (a lifesaving procedure that, until recently, tends to leave a nasty mark) or between your lower right abdominal region and your right hip. Although this little organ has spawned a tremendous debate, it is believed to be a barracks for an important gut bacteria that aids with recovery from episodes of diarrhoea, but without clear evidence showing symptomatic differences between those who have and those who have not had an appendectomy (the procedure for removing the appendix) most consider the organ officially vestigial. Only good for the unpleasant swelling of the organ known as appendicitis which can eventually lead to rupture, shock, and death. When it becomes a problem, it is often removed, for in our contemporary world of the Big C being one of the top three killers, anything that doesn’t serve a purpose only becomes a potential harbourer of cancer.
Vestigial organs are nature’s organic artefacts, clues that serve as a window into our deep past. And as we are facing extreme changes in the present, many have wondered what vestiges will go the way of the appendix in the future. In this list we explore the possible wonders that future generations will carry with them, signs of when ours will be a bygone era.
1. Wisdom Teeth
‘And not a moment too soon’ may accompany a note of ‘good riddance’ to those who have suffered the trauma of wisdom tooth removal (regardless of the amount of ice cream excused during one’s recovery!). The wisdom tooth is a common name given to the third, most distal molar on each of the four quadrants of the dentition. Hints at its vestigial nature come in that not everyone develops these four extra molars, meanwhile some can develop more. Beyond three molars may be called extra wisdom teeth, they are more correctly named as supernumerary molars, but this phenomenon is not restricted to molars and can occur with any type of tooth beyond the standard set. The third molar was thought to be a product of our ancestorial development into a hunter-gatherer society – where food such as leaves, nuts, and meats required additional grinding to ensure proper digestion. Though, the beauty of evolution is that nothing is set in stone, so theoretically if the Paleo Diet trend wins the battle of fad dieting, perhaps over a few generations, we can look forward to even more prominence of wisdom teeth. But, at the moment, wisdom teeth in the context of our shrinking jaw size are set on a course for disaster from impact (when the growing pathways of teeth intersect) to the highly dangerous periodontal disease (gum disease) which is on the same tube line, a few stations down from cancer. As is the case with most vestigial organs, a great debate exists between removing them proactively (healthy or not) or if they should be left to be until we can fully understand how their function has evolved into our current Homo economicus condition.
2. Ancestorial Muscles and Bones
Can you wiggle your ears? If so, then you are one of a dying breed who has retained some usage of the vestigial auricular muscles that can control the movement of our ears. Largely docile, an elaborate network of muscles attaches your external ear to your skull. In dogs and cats, you can witness the use of these muscles as once our ancestors did to focus our hearing and remain alert for predators. It is believed that as our neck mobility improved, there was no need to be able to move one’s ears. These are one of a whole subset of vestigial organs – the retained hardware from our more predatorially preoccupied and tree-bound ancestors. Anyone with little ones at home may have noticed a certain propensity for climbing and those with individuals of a more elderly persuasion may notice that ability rapidly fades with time. One vestigial muscle thought to be used for climbing is the palmaris longus which extends from the wrist to the elbow. You can show yours off by laying your wrist, palm upward, on a table and touching your pinky finger to your thumb, you will notice a cord like protrusion in the middle of your wrist, if not, you may be part of the ten percent of the population that doesn’t have this curious muscle. The coccyx, or tail bone, is also one of those vestiges that has gone into dormancy, fusing into a protrusion that when broken makes for a most uncomfortable recovery. The coccyx is all that remains of our ancestral tail that is theorised to have been used for balance, climbing, and mobility. Before and/or after (the debate rages amongst paleoanthropologists) the trees, the subclavius muscle which runs between our clavicle and first rib was more pronounced and helped with walking on all four limbs. The presentation of extra ribs also ties us to certain living distant relatives, extra cervical ribs (in the neck) were a more reptilian feature and are seen in less than one percent of humans, while extra ribs (at the bottom of the rib cage) is a feature of chimpanzees and gorillas, but only turn up in about eight percent of humans.
One of life’s great mysteries, which seasonally weighs heavy on the heads of many, is why on Earth humans have retained the paranasal sinuses. These sinuses are essentially cavities in the skull that are lined with mucus as a first line of immune defence, good for draining, or failing too, when under heavy assault. It is believed these sinuses developed as a way to lighten the overall mass of the head, except, of course, for those wonderful times of the year when the pollen count is high.
It goes by many names, goosebumps, goose flesh, goose skin, goose pimples – that phenomenon when the skin bubbles up and body hairs stand on end. Although in our present form, this reflex comes in handy as a natural mode of thermoregulation, a way to shield the body from sudden cold, in our ancestors it is believed this reflex played other roles that have faded with the thickness of our body hair. The phenomenon, also known as piloerection, horripilation, and cutis anserina, presents when small muscles, arrector pili, constrict, pulling hair follicles upwards. The presentation is more pronounced where fine body hair exists, particularly on the arms and legs. As is seen in other animals, this reflex can serve as a method of intimidation but can be triggered by fear, strong emotional experiences, and arousal along with exposure to cold temperatures. The loss of this bodily feature would fade alongside the next future vestigial body part.
5. Body Hair
Habits as well as circumstance can have a profound impact on our evolutionary trajectory. And global warming combined with our general preference for wearing clothes ought to be cause for concern to the industry doing gangbusters on personal grooming appliances. As the need for the additional thermal protection decreases, a gift becomes a burden in a more arid planet. It has often been theorised that the further humans get from their less than human ancestors, the less hair we would possess, but these theories are tainted by modernists and eugenicists’ equating evolution to progress, when in actuality it is simply change and would be better served, as such, as a neutral concept. Also, the reality of natural selection and preference may see to human mating rituals, or even religious custom, keeping body hair in the human gene pool a bit longer.
Head, shoulders, knees, and – oh my, the future may see to this old nursery rhyme not aging so well! Feet have undergone quite the transformation which has resulted in the toes losing much of their former function, particularly for grasping and holding objects. In our present, mostly bipedal condition, the need for individual toes wanes, particularly with the influence of shoes where fashion statements have often proven more important than functionality. The importance of toes is maintained on the idea that they are required for balance, which was the case when our walking gate was more focused on balancing along the midline of the foot. Over time it has been noted that our balance has shifted more to the inward side of the big toe, and thus the need for individual toes is less and less necessary for keeping us upright. It is projected that our feet could evolve to resemble how they appear in shoes and webbed feet could come in handy should our need to live in more aquatic environs become necessary.
7. Sex organs
Have you ever wondered why men have nipples? Believe it or not they are fully equipped to perform the same task as female nipples and given the right hormone cocktail, voilà lactation. Embryology shows that we all start as the phenotypic default you might call female, only later in development do our genes tell us to crank up the testosterone or oestrogen to bring on secondary sex characteristics. But before this happens, the nipples have already formed, doomed to remain dormant for some. And while natural selection may have made these an important element in certain mating rituals, it could also be the case that the utter uselessness of male nipples could go the way of the dodo. But who ever said vestigial organs had to be the product of only natural happenings? In our advancing world of genetic manipulation, it is not hard to imagine natural reproduction one day being viewed as archaic and pastiche. And if scientific advancement renders organs useless, then best to be away with them as even today they are critical sights of cancerous metastases. Of course, this simplistic scenario does what we are all too good at doing at the present, ignoring important discussions on sex, gender, and identity that we need to be having.
8. Digestive System
The human digestive tract has been one of the key areas of change in human bodies since our first arrival on the planet. From the biological mechanics to the ecological relationships needed to be maintained with organisms that live or simply pass through us involves a highly adaptable mechanism for homeostasis – balance. Since we started cooking food, our digestive system radically changed (and now we cannot simply eat raw food anymore without serious consequences) and moving into more contemporary times fad diets and new methods for food production (GMOs and lab-produced food products), and even climate change is pushing the uncertain future of our digestive systems to the edge of chaos. Perhaps we will move towards more vegan lifestyles, perhaps the scenario of all food being in the form of a swallowed pill will come to pass, and perhaps we will find a way to sustain ourselves without the consumption of other things. However it turns out, our organs could form new lobes (think of the multiple stomachs required for a cow’s digestion) and the whole bacterial ecosystem of our gut could radically change. And that’s just speaking in terms of natural evolution, 3-D printed organs and external interventions make the potential futures of the digestive system nearly limitless.
The human brain can be described by a variety of metaphors from supercomputer to God’s house for the soul, but one often forgotten is the brain’s semblance to a muscle. Muscles, if left unused, can atrophy and shrink just as quickly as they can be bulked up through overexertion. Similarly, the brain hangs in the balance between bulking its neurological pathways and cerebral atrophy. This is why it is often recommended that as we age, we do brain puzzles, read, and even dedicate ourselves to the lifelong vocation of learning. Yet, like all development, development for development’s sake can be fraught with peril. It is not just important to work the brain out, but keep it open to new ideas and approaches to the everyday struggle of life. As we are learning from patterns on social media and have seen in geriatric studies, it is not just lack of use that causes brain atrophy, but the opportunism inherent to all biological systems and the danger of routine that not only minimises the use of our brains in a given day, but allows for the degradation of old pathways and a resistance to change. Targeted and online advertising methods thrive on this to their advantage. The rising intervention of technology and artificial intelligence are the latest and most dangerous cultural development that renders our brains no longer needing to be as sharp as they used to have to be. Generation Z is unfortunately becoming the ultimate guinea pig for how human brains will develop differently with a cradle-to-grave existence assisted by smart machines. Imagination will be one of the first causalities, but this is only the beginning, the more we ask Siri, the less we need that complex organ that separates us from other species in the kingdom animalia.
10. The Lot
But why stop at just the brain? If that organ can be replaced by chips and education replaced by downloads, why not replace the whole body for something better, something more machine like. It’s the ultimate sycophantic dream of posthumanism. But, again, why stop with better bodies, why not move beyond bodies. Perhaps human society can thrive in the cybersphere. The metaverse is only the beginning. Evolution is simply a tool to help us cope with the limits of our bodies – the ultimate metaphor of limitation. Without bodies, we no longer need evolution or progress, right? Why simply augment when we can go full transcendence? What’s the worst thing that could happen?
Bonus: Unthought Returns
In looking to the futures, we quickly get carried away with the upward, far-reaching ideas, losing sight of the fact that the future is and always will be multidirectional. Our needlessly dichotomised thinking conditions us to see past = back and future = forward, but the future can also go back, while actually taking us towards an advancement. Take the example of the plica semilunaris, it’s that little doodad – bulbus fold of flesh – on the inner crevasse of your eye. That little guy is thought to be a vestigial third eyelid that allowed us to, once upon a time, see underwater. Our voice box and lower jaw are thought to be made of the gills we used to bear. Evolution is not necessarily a ladder, perhaps more aptly compared to the Wonkavator – Roald Dahl’s fictional elevator that can move in any direction – able to move however our environment and choices see fit. As global warming continues to ravage the planet, for the rowers keep on rowing and they certainly show no signs that they are slowing, what the world looks like in a hundred or two hundred years will certainly have a profound effect on what our bodies consist of. What is lost. What is gained. And even, what might be replayed.