The Life of a Kidney Stone

Under the right conditions, water and minerals combine to create crystals and stones. Towering stone formations called stalactites and stalagmites grow in caves where water drips though mineral-laden rock roofs.  In the human body, crystals and stones can form in urine, which is a combination of water, minerals and other waste products filtered out of the blood by the kidneys.  If the balance between water and mineral concentrations in the urine tips in the wrong direction, or if the urine becomes too acidic, crystals may form from minerals and coalesce into kidney stones. The physical consequences depend on the size and location of the stones.

Location matters

Stones can form anywhere in the kidney’s “collecting system,” which begins with the calyx, a hollow chamber emerging from the middle of the organ. Urine made by each of your two kidneys fills its calyx and then passes into a long, narrow tube called the ureter. Each ureter connects its kidney high in the back of the abdomen, one on the right side of the spine and the other on the left,  to the bladder located , deep in the center of the pelvis below. The bladder is a reservoir where urine is stored until it is released from the body. Symptoms of kidney stones depend on their size and location in the collecting system and on the presence or absence of other problems such as infection.

When confined to the kidney’s calyx, the most common stones, made of calcium, are small and cause no symptoms. But the calyx is also the site where large, branched stones called staghorn calculi can grow and fill the hollow structure, clinging to the kidney tissue and damaging it even to the point of kidney failure. Staghorn calculi are associated with recurrent urinary tract infections caused by bacteria that that cause precipitation of magnesium along with calcium.  Staghorn stones are often found as a result of the patient developing fever, back pain and cloudy painful urination – all symptoms of kidney infection. These elaborately branched stones may encase bacteria and grow to huge size before producing symptoms such as blood in the urine, unless a small portion breaks off and passes into the ureter.

The worst pain: when a stone stretches the ureter

A kidney stone may pass from the calyx and through the ureter unnoticed, but if it stretches and irritates the narrow tube as it moves along the resulting pain is intense and colicky, waxing and waning in spasms – and often described the worst pain someone has ever experienced.  Ureter pain is felt in the back, between the ribcage and pelvis, or sometimes in the groin or in the testicle. Sometimes fever and bloody urine accompany the pain. Once the stone passes out of the ureter to the bladder, pain disappears.

Bladder gravel

In the bladder, the stone may remain or pass out through the urethra with urination, causing pain with or without bleeding. When stones accumulate in the bladder they are something like gravel, irritating the lining and precipitating frequent need to urinate, burning urination, bloody urine and low pelvic pain. They may also lower the threshold for bladder infections as bacteria cling to the stones, triggering more stone formation and more symptoms. In medieval times, when clothing was changed infrequently and bathing was a yearly event, bladder infections and stones were so frequent and caused such miserable symptoms that people called stonecutters traveled England’s countryside and cities, peddling the ability to remove bladder stones via an incision between the rectum and the urethra.  There are even reports of people performing the procedure on themselves.

Who gets kidney stones?

Kidney stones are more common in men that women and tend to run in families. Obesity, chronic bladder or kidney infections, inflammatory bowel disease or a history of gastric bypass, surgery, and prior history of stone formation are all risk factors, as are some rare forms of kidney disease and even rarer parathyroid gland tumors. Doctors don’t know exactly why people form stones, but dehydration is almost always a factor in their appearance. When water intake is low the kidney responds by making urine very concentrated and deep yellow. Concentrated urine contributes to the conditions that promote kidney stone formation. Morning urine is much more concentrated than daytime urine because most people do not drink water during the night. Deliberate lack of drinking water during the day in order to avoid the need for bathroom use makes some people such as surgeons and airline pilots particularly prone to kidney stones. People who live in very dry climates or who lose a lot of water through perspiration may have very concentrated urine without realizing that they are chronically dehydrated.

Diet may play a role

Another factor correlated with kidney stone formation is a high protein diet, which increases urine acidity, promoting crystallization of calcium.  High salt diets aggravate the tendency to form stones because as the kidney gets rid of excess sodium, it also pulls calcium into the urine. Curiously, while calcium supplement use may produce kidney stones, calcium from food sources does is not a problem. Rarely, uric acid stones occur in people who have the genetic tendency to gout, or who are taking diuretic hormones.

Treatment

Treatment of kidney stones, like their symptoms, depends on stone size and location. Often, a period of pain control and hydration is often enough to get the patient through the acute problem. If not, the stone can be retrieved from the bladder through a cystoscope passed in through the urethra. A ureter can also be dilated through the scope to remove a stone stuck there. Another technique, called lithotripsy, employs ultrasonic waves applied externally to bombard and shatter stones, rendering them small enough to pass out of the body.

Followup

Beyond the acute phase of treatment, patients who have passed stones need evaluation for conditions like gout, urinary tract infection, and problems with calcium metabolism. Analysis of the stone’s composition can help, especially if it is not the common calcium type. Staghorn stones require more aggressive measures, possibly including open surgical removal.

Anyone who has suffered through the life of a kidney stone needs to be vigilant about drinking water, enough to keep urine very light in color at all times. Weight loss if appropriate, decreasing dietary salt and protein from animal sources, and avoiding calcium and Vitamin D supplements are all helpful in prevention of further stones. Sunlight is a safer source of Vitamin D in those at risk for kidney stones.

 

 

A Slip of Memory: Transient Global Amnesia

Search the internet for drugs that cause memory problems and you will immediately become familiar with a fascinating syndrome called transient global amnesia (TGA). A website at the top of the list of results opens with these words: My personal introduction to the incredible world of transient global amnesia (TGA) occurred six weeks after Lipitor was started during my annual astronaut physical at Johnson Space Center.  TGA is not listed as an adverse effect associated with cholesterol lowering drugs, but with 12 million Americans now consuming these products, recognition of this peculiar syndrome by patients and doctors becomes important.  Beyond the tightly controlled world of pre-market drug approval studies, unexpected symptoms need to be noted.

Transient global amnesia is a short–lived problem, over in less than 24 hours. It involves all aspects of new memory formation. Nothing gets recorded during the event and the sufferer fails to remember anything from the event after it is over. To appreciate the disconcerting nature of the syndrome, imagine suddenly losing your ability to put any information into your memory. In addition, you lose access to a few hours or days or even years of past memory, but not to information about yourself. You look around but cannot identify why you are where you are. Depending on how much access to the past you’ve lost, your current situation might be totally unknown to you. With great urgency you question the people around you. “What am I doing here?” How did we get here?” What’s going on?” Someone answers and for about 30 seconds you can hold on to the information. But your ability to put that information into memory has gone offline. You forget that you just asked the question. You ask again, and again, and again, with obvious anxiety. All your other mental capacities work. You can speak, read, write – even drive and problem solve. Except for your anxiety, you are the same person as always. Then the confusion ebbs. You start to encode information again. Your past gradually returns, in chronological order. Once again you are tethered to time and place, but you will not ever remember what went on while you were cut loose and for a little while you might complain of a little headache.

The first descriptions of this odd set of symptoms appeared in an obscure medical journal in 1956. More cases came to light, and by the early 1990s there were a few epidemiological studies that suggested that TGA occurs in about 10/100,000 people, or as many as 25-32/100,00 in the peak age group of 50-80. Far from being a harbinger of impending stroke or evidence of seizures, these episodes seemed to have no correlation with any problems other than a history of migraine and left no problems in their wake. They recurred in somewhere between 5 and 25% of the cases, with one patient having over a dozen recurrences. No definite cause has ever been found, though many physicians have associated them with immediately preceding, physically or emotionally strenuous events.

Very rarely, underlying brain problems like tumors involving the deep middle and frontal areas, where memory formation takes place, turn up in TGA cases, but careful examination of these cases inevitably reveals some deviation from the typical clinical symptoms, or some type of abnormality on neurological examination. TGA research studies, using sophisticated scanning and EEG techniques, suggest that there is decreased activity in areas of the brain involved in memory formation, but give no clue about the mechanisms involved.

In 1990, criteria for diagnosis of the syndrome were published (listed below), and when a diagnosis of TGA strictly adheres to these criteria, it is almost always safe to predict that there is no underlying neurologic or vascular problem. Nevertheless, when a patient appears in an emergency room with TGA symptoms, good practice still requires a CT or MRI scan and an EEG at some point to rule out the remote possibility of an underlying tumor, hemorrhage or seizure disorder.

Reports like those of Dr. Duane Graveline, the astronaut/physician author, are considered anecdotal and not of the same value as information gleaned from statistical analysis of controlled studies .  The cholesterol lowering drugs are in widespread use and considered very safe by most physicians. However, there have been cases of muscle and nerve problems, as well as cases of decline in cognitive function attributable to the drugs, possibly mediated by damage to mitochondria, the power houses of all cells in the body. Since the drugs are viewed as valuable additions to the battle against heart disease and are likely to be used over long periods by increasing numbers of people, it is important to understand and catalogue their unintended consequences.  Once drugs reach large populations outside medical studies, more problems emerge, sometimes beginning as odd, single cases.  In the meantime Dr. Graveline has died after a progressive illness which resembled Lou Gehrig’s Disease (progressive loss of muscular strength and bulk). His memory, however, remained good.

Diagnostic Criteria for Transient Global Amnesia

  1. A witness must be present to describe what happened.
  2. The patient must be unable to form new memories of any kind (anterograde amnesia).
  3. The patient must have full knowledge of his identity and an unclouded state of consciousness.
  4. All other mental functions are normal, including speech.
  5. There are no other neurological symptoms or signs.
  6. There are no signs of a seizure.
  7. There is no history of seizures within the last 2 years, or of recent head injury.
  8. The patient is back to normal within 24 hours.

 

 

 

Floaters

Eventually, everyone sees floaters- the dark wavy lines or spots or cobwebby filaments that drift lazily through the visual field of one eye or the other. Quick eye movements up, down or sideways will clear them from your line of sight, but slowly, because floaters move through a jelly like substance in the center of the eyeball. Like the ghosts wandering around Harry Potter’s Hogwarts School, ocular floaters are most often harmless annoyances. And like so many of life’s problems, they are an accompaniment of aging, particularly in people who are nearsighted (those who require glasses to see clearly at distances).

Blame aging
Aging produces changes in collagen, the structural protein that gives form to much of the body. As a result, we develop skin wrinkles, stiff tendons, unpliable heart valves and brittle cartilage, to name just a few obvious accompaniments of living to old age. Few people know that there is collagen in the middle of the eye, which is filled with a glob of jelly-like material called the vitreous humor. Most descriptions of the vitreous humor conjure up a picture of a clear, colorless ball of Jell-O that fills the posterior chamber of the eye (the space between the lens behind the pupil and the retina lining the interior of the eyeball). The vitreous keeps the eyeball from collapsing and helps hold the retina in place.

Vitreous humor – a complex structure

But appearances are deceiving. Though the transparent, jelly-like glob is composed of 99% water, it is also a delicately complex structure in which collagen plays an important  structural role. Like skin, the vitreous ages. Along with the years come the floaters.
You are born with the vitreous humor in place. Should it be removed, by surgery or trauma, you will not grow another. This is in contrast to the aqueous humor, a clear liquid that fills the space between the cornea that protects the eye and the colored part called the iris (called the anterior chamber of the eye – see diagram). The aqueous humor is manufactured by the ciliary body, a muscular structure that gives rise to the iris. From its manufacture point just behind the iris, the fluid circulates through the pupil, fills the space behind the cornea, and exits via a channel  formed by the junction of the iris and the cornea. This evenly balanced system of fluid manufacture, circulation and exit controls the pressure within the whole eye. No such recycling system exists for the vitreous humor – as in Las Vegas, what happens in the vitreous humor stays in the vitreous humor.

eye anatomy

What happens without recycling?

The  collagen structure within the vitreous humor is an airy honey-comb of interconnected collagen fibrils – microscopic fibers cross-linked and held apart by chemical and electrostatic forces. The network is loosely attached at some points to the retina that lines the inside of the back of the eyeball. The spaces in the honeycomb contain a solution of many minerals and polysaccharide molecules (chains of sugars) dissolved in water. The collagen network is, in part, held open by the pressure of the watery solution. With age, the system has mini-collapses of collagen fibrils, resulting in some clumping of the collagen networks. Floaters are the result. Occasional macrophages (white blood cells that clean up debris) float about, but they are a lonely workforce.

When are floaters more than a nuisance?

A sudden increase in the number of floaters, accompanied by transient light flashes, is sometimes indicative of a segment of the vitreous pulling away from an attachment point on the retina. This condition is known as a posterior vitreous detachment. By itself, a posterior detachment is not a serious problem, but occasionally the point of shrinkage also pulls the retina away from the vascular layer underneath it. Now you have a retinal detachment, and your vision either develops a blind spot or the sensation of a curtain pulled over part of the visual field. Such symptoms require immediate ophthalmologic evaluation and treatment to prevent further detachment of the retina.

Treatment

There is no special treatment for floaters but at times, floaters are troublesome enough for an ophthalmologist to attempt to remove the vitreous humor entirely. The surgery is very difficult and fraught with hazards such as retinal detachment or damage resulting in partial blindness.  Called a vitrectomy, it is a procedure done more often  for other reasons such as  eye trauma. After vitrectomy, the vitreous has to be replaced to maintain the shape of the eye. Research by physicists and bioengineers on suitable replacement substances has been the biggest source of information about the physical nature of the vitreous humor and the origin of the near universal phenomenon of floaters. However, to date the replacement is still done with saline, which is then naturally replaced by the same fluid that fills the anterior chamber.

Natural history of floaters 

What happens once you begin to notice floaters? They come and they go – eventually sinking out of view. The process is very slow because there is no circulation pattern in the vitreous humor and the body has not assigned a vigorous cleanup crew to the problem. Because of this slowness, and because the vitreous passively absorbs substances from the bloodstream via the blood vessels in the retinal layer, coroners sometimes use the vitreous humor to search for toxic substances like drugs at autopsy. Chemical traces remain there after they have disappeared from other body fluids; and. the vitreous humor also retains its integrity longer than other parts of the body.

Plato’s cave

As for “seeing” floaters? You are not actually looking at the clumps of collagen. Just as in Plato’s story about people in a cave interpreting shadows created by firelight as reality, you see only the shadows of floaters cast on the retina by light coming through the pupil. For this reason, floaters are clearest when you are looking at a bright background such as snow or water. Even when you see floaters with your eyes closed, light is passing through the thin eyelid and into the pupil, the only opening in an otherwise light proof box. Who knew these little annoyances could illustrate a philosophy lesson?

 

 

The Role of Alcohol in Dementia

O God, that men should put an enemy in their mouths to steal away their brains!”

Cassio (Act II, Scene iii)    William Shakespeare

The Diagnostic and Statistical Manual of Mental Disorders, the official compendium of acceptable psychiatric diagnoses, lists a syndrome called “alcohol-induced persistent dementia.” This condition was once described as the “common end reaction of all alcoholics who do not recover from their alcoholism or do not die of some accident or intercurrent episode.”  But alcoholic dementia has never been a frequent diagnosis and alcohol is still not listed as one of the risk factors for dementia. In guidelines for reduction in harm from alcohol consumption, the governments of the US, Canada, Australia, Great Britain and the EU all acknowledge the role alcohol plays in a host of chronic health and social problems, but dementia is not mentioned. Growing epidemiological evidence suggests that this omission is an error, and even that alcohol-related dementia might be a “21st-century silent epidemic.”

Epidemiological Evidence

Some evidence comes from a 2018 British study that correlated the appearance of dementia with the alcohol habits of British civil servants over a period of 23 years. The data showed that people consuming more than 14 units of alcohol a week (the equivalent of 60gm of alcohol or about 6 drinks) had an increased risk of developing dementia.  The more they consumed, the higher the risk.  A 2018 French study concluded, from a vast analysis of hospitalizations related to alcohol disorders, that there was a distinct association of alcohol use disorders with all kinds of dementia, that alcohol was responsible for a much greater proportion of dementia than previously estimated, that alcohol should be considered as one of the main causes of dementia appearing before age 65, and that, of all the risk factors related to dementia, alcohol was the easiest one to change.

A subject that doctors and patients avoid

Abstinence, over time, improves the symptoms of alcohol related dementia. Why, then, do we not make vigorous attempts to educate patients and families in the early stages of dementia evaluations about the possibility that ceasing all alcohol intake might be beneficial, and certainly not harmful, no matter what the cause of the dementia? Doctors who evaluate patients for symptoms of dementia should question patients carefully about their current and past alcohol use patterns. Often, they do not. Patients being evaluated for dementia, and the concerned family members who bring them to the doctor, should provide honest and accurate accounts of alcohol use. Often, they do not. Alcohol use is a subject which people tiptoe around for many different reasons, but one which should be addressed openly and compassionately, with an educational goal.

The path of alcohol through the body

The first goal is understanding how alcohol affects the brain, and how age and sex influence its effects. Alcohol is absorbed into the bloodstream within five minutes of entry to the stomach. On its first pass around the body, it is metabolized by an enzyme called alcohol dehydrogenase. This enzyme declines with age and is less active in women than in men. Alcohol that is not metabolized immediately circulates in the blood and is measurable as a “blood alcohol level.”  Some of it goes to the liver where it is broken down to a substance called acetaldehyde and some is broken down to acids – all these chemicals escape in urine, as well as in your breath and through the skin (the source of the “morning after” boozy smell that lingers long after the party is over).  In the brain, the un-metabolized alcohol enters brain cell membranes and dissolves some of their fats, changing receptors that transmit information from cell to cell. As more and more alcohol is absorbed, blood alcohol levels rise and a predictable sequence of events occurs: mild euphoria, mild in-coordination, then imbalance, confusion, depressed mental activity, stupor, deep anesthesia, and, ultimately, death.

Tolerance reflects changes in brain cell membranes

Depending on tolerance, alcohol’s effects on brain function occur at varying blood alcohol concentrations, with some alcoholics able to remain awake and alert at blood alcohol levels that might kill novice drinkers. Enzymatic breakdown of alcohol occurs a little faster in people accustomed to heavy drinking, but most of their tolerance to alcohol’s effects comes from persistent changes in their brains.

Altered brain cell membranes change the personality

Brain scans of chronic alcoholics typically show atrophy – shrinkage of the brain tissue, and, at autopsy, the brain of a chronic heavy drinker may show loss of some cells and white matter. But unless there are coexisting problems like old trauma, Alzheimer’s disease or vascular damage, there is no specific pathology that identifies alcoholic dementia. In life though, the result of altering brain cell membranes chronically by dissolving parts of them in alcohol is dementia – the gradual disintegration of a personality structure with persistent impairments in attention and memory, problem solving, language use, planning abilities, visuo-spatial understanding, and in emotional control and responsiveness. Memory problems can be the most prominent feature in alcoholic dementia, and emotional instability and paranoia also occur.

Not all bad

Is all alcohol bad for the brain? Not necessarily. Both studies mentioned earlier confirm a modest increased risk of dementia in strict teetotalers, an observation made many times in the past and never well understood. Research in the last decade suggests that small amounts of alcohol enhance the function of the “glymphatic” system, a term coined to describe the way spinal fluid flows deep into the brain and clears waste from it.  Sleep and exercise also heighten this pattern of spinal fluid flow. (Exercise is known to have a protective effect on the brain, lowering dementia risk. Sleep deprivation, at its extreme, produces symptoms indistiguishable from dementia. More research into the glymphatic system may help explain these observations.)  The slightly increased risk of dementia in teetotalers is not considered a reason to begin drinking for someone who prefers to abstain.

Understanding alcoholic beverages

Knowledge and awareness are keys to moderation in alcohol consumption. The alcohol in beer and wine comes from fermentation of sugars. Alcohol in whiskey, vodka and other spirits comes from distillation and the process produces additional chemicals which are like alcohol, but more toxic.  The percentage of alcohol in beers, wines and spirits can vary widely. As a rough guide, standard drinks like a 12 oz. beer (typically 5% alcohol), a 5 oz. glass of wine (12%alcohol) and a 1.5oz. shot glass of distilled liquor (40% alcohol) contain roughly the same amount of alcohol – 12-14 gms.  Label reading is important since the percentage of alcohol can vary significantly among different beers and wines.  A 12 oz. craft beer may be the equivalent of 1.4 drinks because of a 7% alcohol content.

The risk of dementia begins to climb after about 60gm/week for men and 40gm/week for women on a regular basis – about 5-6 servings. It takes about an hour to metabolize 150 mgm of alcohol/per kilogram of body weight, which translates to about 1 oz. of 90 proof whiskey for a man of average weight. Take in more over that hour and the excess alcohol circulates in the blood and begins dissolving membranes in the brain, and mental effects appear. As alcohol is cleared from the body recovery occurs in the brain and the mental symptoms resolve. With chronic, repetitive, excessive exposure, some changes fail to reverse and dementia is the result.

If you are concerned about alcohol “stealing away your brain,” and want to rethink drinking, there is much useful information for you at the link below.

https://www.rethinkingdrinking.niaaa.nih.gov/How-much-is-too-much/Whats-the-harm/How-Can-You-Reduce-Your-Risks.aspx

The Gratitude Attitude: Five Best Days

Gratitude is an attitude that mental health professionals say promotes mental well-being. They advise practices such as noting three good things about each day and writing them down at night. Studies actually show that such habits durably improve mood. In the giving spirit of the Christmas season I would like to share with you one of our family traditions that, in retrospect, I realize promotes the gratitude attitude over the course of each year.

We began taking our boys to Colorado to learn to ski when they were very little. Economic and time constraints meant one week a year, determined by my husband’s surgical on-call schedule. That week included the turn of the year on New Year’s Eve. Children’s skiing torchlight parades, followed by dinner at a Chinese restaurant and early bedtimes gradually gave way to a movie (usually laughably bad) followed by dinner at a locals’ Italian restaurant with paper-covered tablecloths and crayons for doodling. The family expanded to include our boys’ friends – first as children and teenagers along for a vacation, then as young men who worked as ski instructors. Somewhere along the way we began the habit of discussing our five best days of the year over New Year’s Eve dinner.

The crayons and the paper table covers are very convenient – everyone begins jotting down their five best days, in order, almost as soon as the menus arrive. The entire dinner time winds up devoted to going around the table in five rounds, hearing from each person about what made each wonderful day and how they decided where to rank it in the list. The choices are life stories in snapshots, changing with growth and priorities. They are funny, poignant and surprising. We also hear from people who have been with us on past New Year’s Eves, calling, e-mailing, or texting their top five days, sometimes accompanied by pictures. They all get heard.

The reason this tradition promotes gratitude is a very practical one. If you know you are going to have to come up with your five best days of the year on New Year’s Eve you learn pretty quickly that memories are weak. You cannot cram for this test. You have to start noticing potential top five days as they happen over the course of the year. You start writing them down. Pretty soon you actually have a little journal and it contains good stuff. The good things that happen in life start to break into your awareness and compete with danger-surveillance program that runs continually in the background of your mind. All good, with none of the side effects of mood enhancing drugs (which fail in the long run anyway).

Just as a matter of historical interest, we traced this tradition back to its origins. It actually began with my husband’s surgical training at Massachusetts General Hospital. The surgical interns and residents on the general surgery service met at the end of each day and were asked to talk about the cases they helped with and to explain what they had learned. The practice helped everyone process what they had done and learn from their experiences. As a family, we were always sit-down dinner people,  with candles even when there was still a high chair at the table. Like the surgery residents, we  always talked about everyone’s day. Skiing days included lots of bests. Best fall, best jump, best run, best lift ride. The evolution to a summing up of bests at the end of a year was inevitable. What is a surprise is the way the practice has continued and spread from our families to others. Maybe you would like to give it a try.

Human Diversity: A Mind Thing

(A version of this essay was published in Minnesota Medicine in March, 2005.)

The first snowy egret I ever saw was standing in a shallow pool, a beautiful white creature with a wispy headdress floating in a gentle breeze. When he lifted off, trailing his long black legs, I was startled by a flash of bright yellow – he looked like he was wearing a child’s rubber boots, designed to hug a bird’s clawed feet. He did a loop around the pond in  flying low in a peculiar, non-aerodynamic position. His legs hung down rather than stretching out parallel to his body. He dipped closer to the water and his dangling yellow feet brushed the surface. He’s landing, I thought. But he didn’t. He repeated the maneuver four times.  He’s afraid to land, I thought. But then he touched down with hardly a splash, and dipped his beak to catch a fish, then another, and another. In a moment of bird-watching epiphany, I realized that his feet were like a fisherman’s lure. He’d rounded up his lunch. 

I looked around the pond. I’d just watched a bird with bright yellow feet use them to attract the curiosity of his prey. Across the water was a bird with a lower bill that expanded into a pouch to collect fish as he skimmed, openmouthed, over the water. Perched high above was another, just about to dine on a large fish he’d  skewered with  fearsome talons. What an impressive display of diversity!  If people were this diverse, New England fishermen would grow waterproof, blubber lined hands, typists would develop extra fingers, and mothers really would have eyes in the backs of their heads.  

But people are pretty much the same as far as their bodily equipment goes.  Five fingers on each of two hands, ten toes divided between two feet, two eyes, upright posture, and a narrow range of physical abilities, notwithstanding the spread between ordinary and Olympian. The traits we associate with human diversity are superficial – hair color and texture, skin color, facial appearance. Almond shaped or round, eyes still see. Long, elegant skeletal frames and short squat ones all support bodies against the universal force of gravity. Skin pigmentation protects the body covering from the sun, more or less depending on the power of the sun in the areas of the world where the people originated. We are much more like each other than we are different in our biology. The birds have it all over us in the diversity contest.  

After my egret experience, I packed up my binoculars, got on my bike and headed home, humbled a little by the thought that all of the talk and concern about diversity among people is overblown, maybe just another representation of man’s abiding sense of self-importance. But along the way I passed bikes and cars, houses and stores, a radio broadcast tower, and a museum.  I crossed a bridge between two islands and waved to a fisherman in his boat. And I realized that each of these man made things  I passed began as an idea, somewhere, some time, in somebody’s head. We might not differ much in anatomy and physiology, but no two of us have identical thoughts. The mind is the site of the real diversity among humans. The mind is plastic and ever developing. It records, collates, recalls, communicates, and combines unrelated information in new ways. Yellow feet catch the eye, but minds change the world.

No more posts.