Every day, you execute one of the most complicated operations in a perfect coordination of timing and you do it before anything else in the day. It’s a series of multiple actions that involves a selection of muscles including the tractor spine, transverses, quadriceps, rectus abdominis, gluteus maximus and many more.
Of which, the contraction and relaxation phases of each work in seamless intervals to ensure a smooth transition of you throwing back your blanket, sitting up, bending your knees, swinging your legs over the side of the bed, pushing with your arms and shoulders, leaning your weight forward over your feet, then finally straightening your body. And sometimes we do this with our eyes closed.
Getting, or dragging at most times, yourself out of the bed is not the only fluent set of movements you do daily. As you start making your way to the bathroom, you are likely unconscious of the balancing act you are performing. Six-legged insects move stably at any given time, as with four-legged beasts that can keep a tripod on the ground when one limb is lifted onward. When we walk, as cognitive psychologist Steven Pinker has observed, we repeatedly tip over and break our fall in the nick of time.
This miracle of motion is what allows babies to master bipedal travel at just a little over a year of age, while highly advanced robots still struggle to manoeuvre awkward two-footed steps. As of now, bots capable of such locomotion hardly have the same frame as we do, let alone the gait of a combination of heel strike, roll to the ball of the feet and toe lift. That’s just referring to flat terrain and walking in a straight line.
Yet, the operation of your legs does not even come close to the intricacies of your two upper limbs. You pick up and utilise your toothbrush effortlessly. The remarkable stunt requires an exact configuration of grasp shaped with your fingers and pressure holding the toothbrush in place without dropping it. More astonishing then that these same hands can adapt to an unparalleled number of grips specific to the function at hand, pun intended.
“Such mighty instruments are the hands of a man,” ancient Greek physician Galen has famously praised, expressing admiration for the tool-like attributes that surpasses the defensive endowments of other animals, “…and also gives you, by the handwriting, the means of conversing with Plato, with Aristotle, with Hippocrates and others of the ancients.”
Of course, the means to convey thoughts and ideas is not limited to inscriptions alone. They began with spoken language from thousands or millions of years ago, depending on your chosen narrative. As you open your mouth to utter the first coherent words of the day, you partake in a skill that other primates can only mimic to a finite extent.
Apart from the expanse of vocabulary and their associations registered in your frontal lobe, Broca’s area, Wernicke’s area and their connecting band of nerve fibres called arcuate fasciculus in the brain cooperate to handle the understanding and formation of your speech. Additionally, as demonstrated by recovering stroke patients, your motor cortex is equally vital. By controlling the muscles of your throat, jaw, lips and the extraordinary gymnast that is your tongue, discernible sounds are patterned.
“What?” Your spouse responds. Or perhaps not so discernible after all. As you turn back ready to repeat your morning slur more audibly, there is no doubt that the person before you is your spouse. Without sounding like a plot for a domestic thriller, how do you know if someone is indeed your family member? At the base level, you recognise their face in a matter of microseconds, a detection that programmers have used years of database training and human-input algorithms to replicate in artificial intelligence.
Besides the 205 neurons that biology professor Doris Tsao of California Institute of Technology has uncovered to be responsible for this, your eyes work to piece the features together, which demands not just colour, but depth perception as well. When matched with our own mental record, identification is achievable even when the image is distorted, ie. when sporting extra wrinkles or even just having a different facial expression.
Right now, your spouse looks a little annoyed. You are able to ascertain with relative accuracy almost automatically. Your amygdala fires off, reading into body language, facial cues and tone. Deciphering is only feasible with an unimpaired limbic system, a feat not easily accessible with autism or Asperger’s syndrome. As social creatures, the competence to infer and reciprocate intentions beyond diction is incredibly necessary for survival.
Though not as indispensable as your capacity to breathe or keep your heart beating—tasks you are barely conscious of or even able to regulate for the latter. Still, these activities continue to run without hiccup for a greater portion of your life and are even fitted with a built-in software of back-up processes like clotting a cut or raising internal temperatures to kill viruses should things go wrong.
Your body is truly a wonderland, without the sensual connotation of John Mayer’s hit (or with, it’s your body, your choice).
With its vast number of functions, it’s no surprise it appears peppered within our language, as Anatomies: The Human Body, Its Parts and The Stories They Tell author Hugh Aldersey-Williams points out. We pay through the nose, cut our teeth, wear our heart on our sleeves, lend a helping hand, have two left feet or even act like an… anus.
As much as Galen was right about our hands, we’ve surely come some way from his theory of the brain, heart and liver governing the corresponding head, thorax and abdomen. We certainly contain more fluids than Hippocrates’ four humours: blood, phlegm, black bile and yellow bile. We possess more than five senses, comprising pain, balance and temperature to name a few, and are still learning how immeasurably complex our physical bodies are.
“I challenge any man to produce, in the joints and pivots of the most complicated or the most flexible machine that was ever contrived, a construction more artificial, or more evidently artificial, than that which is seen in the vertebrae of the human neck,” philosopher William Paley states in his argument Natural Theology, or Evidences of the Existence and Attributes of the Deity Collected from the Appearances of Nature, likening the human body to the elaborate pocket watch, impossible to assemble without a maker’s intervention.
We have not even fully discovered all the motivations behind our gestures. Science still has no definite answer for why we yawn or why you now feel the urge to do it the more you think about it. While all the marvels this product of evolution or design of deity is equipped with can scarcely be encompassed here, there are some highlights worth being grateful for.
It’s not plausible to summarise this behemoth in a couple of sentences, especially when researchers consider its storage capacity to be virtually unlimited. With an estimate of 86 billion neurons adding up to a quadrillion connections, information can travel almost over 400km/h. So, a piece of brain tissue the size of a grain of sand can contain a billion synapses.
Weighing approximately 28g at 2.5cm in diameter, the visual instrument is composed of two million separate working parts. As the second most complex organ after the brain, it processes 36,000 bits of data an hour with the body’s fastest muscles. The extraocular muscles proficiently allow your eyes to focus in the same direction in a single 50ms flick, and doing it persistently will not tire them out as quickly as making you seem like an extremely suspicious person.
You’ll be surprised to know they carry out their responsibilities unfailingly and it’s your tired brain that’s guilty of not interpreting their signals faithfully. Our comparably technicolour vision is derived from their 120 million rods in the retina and 6.5 million cones responding to detailed hues, going as far as to detect 500 shades of grey.
Key to our retro-nasal olfaction where your chips taste more than just salt on crinkly potato with the added whiff, the nose grants us to taste more than any other animal. Surprisingly we can sniff up to a trillion different scents and aces the recall department at 65 percent precision after an entire year, as opposed to visual recall which declines to 50 percent after three months.
While we’re all aware of our advanced opposable thumbs, the unique flexibility in metatarso-phalangeal joints also contributes to the great torque facility in the fingers. This means that rotating your pinkie to meet your thumb is more impressive than you think.
Its sophistication, paired with wrist deviation, permits another mode of communication—sign language. With 20 major joints, 27 bones, 34 muscles, 48 nerves and at least 123 ligaments, it makes sense to have nearly an entire quarter of the cerebral cortex devoted to its control. In fact, a hand transplant takes longer than the average heart transplant. And let’s not even get started on fingerprints.
You’ve probably learnt in school how it pumps around 4,730 litres of blood 100,000 times a day. Oh, and through close to 10,000km, which gives it a power output of between one and five watts. The daily energy output is equivalent to driving a truck to the moon and back over a lifetime, according to British general practitioner and writer Dr Hilary Jones.
Ah, our largest organ can be stretched out to an average of 1.95sqm. Consisting of millions of blood vessels and thermoreceptor nerve endings, we’re practically wrapped in a thermometer. Aside from temperature, we are also able to indicate heat, pressure and vibration amongst many other sensations.
It appears as both thin, delicate eyelids, but has a durable protein layer called keratin to protect from germs and toxins. We shed a whole layer of epidermis every 24 hours and have this barrier protecting our internal from the exterior renewed completely every 28 days.
Having heavy bones could never work as an excuse for weight when they take up only generally 15 percent of your body mass. Its dry weight is sometimes even lighter than some plastic replica skeletons used for medical purposes. The roughly 206 bones (because some fuse with age) are comparable with copper and cast iron in strength, typically resisting a 1.5-tonne load per square centimetre before breaking.
Its structure alone is already optimised for endurance. The tubular column of ‘holes’ constitute a distinctly engineered network of struts situated where they are likely to experience forces upon. Only vulnerable in torsion, the bones in a child’s arm is enough to support the weight of, say, a family car. Altogether, the skeleton makes up a highly developed mechanical system.
Just picture holding up a shopping bag and all the hinges compressing and stretching where the weight passes through from hand to arm, arm to shoulder, collar bone to shoulder blade, down the spine into the pelvis and distributing through each leg on the ground. What a piece of work is a man!
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