The heart of the matter

Heart doctor Michael Henein steps back to consider the unseen and unique wonders of the human body’s design.

Michael Henein

Professor Michael Henein is a consultant cardiologist, and a Professor of Cardiology at Umea University, Sweden.

A model of a human heart on a short stand.

Photo by Jesse Orrico on Unsplash.

Shakespeare famously asked:

“What a piece of work is a man, how noble in reason, how
infinite in faculties, in form and moving how express and admirable, in action how like an angel, in apprehension how like a god! the beauty of the world, the paragon of animals—and yet, to me, what is this quintessence of dust?

Humans may be complex, capable of great heroism and deep depravity, yet it is worth stopping for a moment to look at the human body and mind to marvel in what we have become, and how we are made.

The visible design of the human body points out common features shared along with other members of the animal kingdom. Examples of these features are: two eyes, two ears, two nostrils, one mouth and four limbs, attached to a body and head. Detailed study of different seen parts of the body may, however, show some differences. For example, the presence of fingers and nails, hair distribution as well as a developed tail. While most members of the animal kingdom have teeth and a tongue, those two could also vary in their number and size, respectively, according to different species. Genetic investigations have shown that we humans share 99 % of our genes with animals, suggesting that our “earthly” component shares a common origin. Indeed, the twenty first century scientific findings match what is written in the Genesis story of creation, a story written over 3,500 years ago, well before genetic sciences came to light.

Creatures great and small

As for morphological differences between animal species, it is difficult to naively conclude why some are wild while others are man-friendly-even if the wild ones have different shapes, design, dietary habits, body size and life span. Other important observed features of the members of the animal kingdom are that they are all born, they all age, then ultimately die.

If we are to look at the unseen features of the members of the animal kingdom, we can again identify similarities. For example, all have a gastrointestinal tract, a cardiovascular system, a reproductive system, a respiratory system, a urinary system and much more. While these systems may differ slightly between species, the overall structure and function achieve similar purposes. For example, heart speed is faster in small animals like rats compared to big ones like elephants who have very slow hearts. Likewise, the respiratory system and the number of respiratory cycles per minute are significantly faster in running animals compared to the sedentary and slowly moving ones. Finally, the number of offspring also differs in different species, being just one at a time in big animals like elephants and horses, and many offspring in small animals like rabbits and mice. Such paradox between the number of offspring and animal size makes you think of the important determining role of the activity of those animals.

Unseen wonders

Now to turn to the rest of the animal kingdom and the unseen features of the human body. To start, let us look at the amazing functions of the human brain and its various functions. When humanity is sometimes described as the crown of creation, such a description is based on the superiority of human brain function and skills. Its sophisticated structure and how vital centres are created deep in the skull, to be protected from traumas, make you marvel. Also, the brain controls the different functions of the whole body, with its sensory and motor activities, various vital system functions including the lungs and the heart, all endocrine glands’ function, in addition to various receptors and centres that allow utmost precision and accuracy in everything we do. An example of this kind of precision is a doctor feeling a vein or an artery with the tip of a finger to insert a needle or a musician moving a finger a few millimetres while playing a violin, to produce the exact sound needed. Furthermore, the integrated function of human muscles, nerves and spinal cord is also amazing, let alone the synapsis between the nerve endings and muscle bundles, the chemicals secreted in them which allow electric stimulus transmission from the nervous system to achieve the motor function and desired movement.

The human brain also has the unique feature of storing knowledge. Of course, we should not ignore the importance of the training and programming ability of human brain. We learn how to drive a car, how to play games, how to study, how to operate safely on a sick patient. Such acquired skills are quite limited in other members of the animal kingdom. Moreover, the human brain has the unique ability to invent, discover, improve and correct errors it identifies.

Another very unique feature of human brain is its ability to conduct speech, a feature of humans that is under-developed in other members of the animal kingdom. While most animals can make noise and sounds, only humans can articulate words, sentences and even sing very complex songs. This unique ability seems to be the underlying mechanism behind the development of languages which are based on the human ability to talk and transmit information and knowledge by words and phrases.

The unseen brain has allowed human life to develop over time, building skills and achievements from generation to generation. Millennia ago, humans lived in huts together with animals, and now they build houses and palaces to live in. Centuries ago, we used donkeys, horses and camels to travel but now we use cars, trains, ships and airplanes. Our ancestors burned wood and coal to cook and to warm but now we use electricity to do these.

When we look carefully at the unseen parts of the human body, we also realize that we cannot alter any of it, despite the scientific advances made over the years. We can understand what harms our body and take measures to avoid it. Out of the ability of our brain to discover and invent, we have now produced science-based means for curing various diseases. Consider how we can replace a dysfunctional heart valve or a mobility-limiting joint. These inventions have resulted in a better quality of life, alleviating of symptoms, even helping to avoid early death, in some cases such as heart disease and cancer.

The heart of the matter

Another unseen source of life in humans is the heart. This fist-size organ is so complex in its structure and function. Recent scientific advances have enabled us to study heart function in milliseconds, hence the development of pacemaker treatments. They have also allowed clear imaging of the inside of the heart and the identification of pathologies, developments that guide practitioners to the optimum treatment of heart conditions. Recent discoveries have also allowed us to better understand how people develop coronary artery disease and how the pathology starts at the innermost layer of the arteries, particularly in individuals carrying significant risks for atherosclerosis including, smoking, high blood pressure, diabetes, high cholesterol and obesity. Amazingly, obesity has been shown to be the strongest underlying cause of other risk factors, hypertension, diabetes and hypercholesterolemia. So, nature cannot be blamed in many of these patients but our own patterns of behaviour. Science has shown that walking at least 5,000 steps each day, complying with the design of our body, reduces the likelihood of developing coronary artery disease by 15 per cent.

The unseen physiology of the rest of our body systems and the interaction between systems make us wonder how we are made. A rise of our body temperature by one degree due to a bug infection affects all body systems from the brain to the heart. A virus which cannot be seen by the most powerful microscope can destroy our lungs and cause premature death, as was the case with COVID-19 and others.

Finally, human inventions in the form of powerful microscopes have allowed scientists to study the human cell, which is the smallest living component of our body. Such small cells cannot be replicated in any factory in the twenty-first century, despite the vast scientific developments that surround us. You'll be surprised to learn how complicated and meticulously fine-tuned a human cell is and also how it functions, connects with other cells and other parts of the body. An example of this is the interaction between body minerals, calcium, sodium and potassium with heart and muscle individual cells. Such a function is critically controlled by many factors such as time, electric stimulation and pressure differences producing remarkably harmonious contractions and relaxation of the muscles without missing a beat.

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Biology

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Wildness

10 July 2025

5 min read

There’s a sting in the tail if we construct lessons from nature

Don’t be like the bees

Julia Kendal

Juila is a writer and social justice advocate.

A bee keeper hold honeycomb to the light

HiveBoxx on Unsplash.

‘Be like the bees’ we hear not infrequently. These furry hive dwellers have been coopted by many, from socialists to capitalists, to put a point across. One party draws on their social structure as an inspiration, another their worker bee ethic. They are indeed an example to us. And yet at the same time, bee communities do things that we would find reprehensible in fellow humans. Male bees are expelled from the hive when they are no longer considered reproductively useful. The bees we see out and about this summer are often the oldest, sent to do the dangerous foraging work because they are considered the most expendable. This was a jarring discovery for me, reading it in Katherine May’s timely book, Wintering, during the first COVID-19 lockdown. I was one of the millions shielding and being protected by the ways that society shifted to serve the most vulnerable to the virus; bees, I had just learned, would not behave like this. There are some limits, it seems, to the lessons we construct from nature.

For we do love to construct them. Spend a moment on LinkedIn or Substack, and there are a multitude of articles drawing lessons from the world around us and the creatures we share it with.

This impulse is not new; throughout history, people and communities have done this. People’s relationship with nature is not static or homogenous. The wilderness has been variously a place of fear to be avoided, of growing wonder as described by the Romantic Poets, a site of knowledge neglected by those in power but maintained by others, often women and indigenous communities.

What strikes me about the current trend is that it seems to push to an extreme of unquestioning veneration: nature is perfect and our whole teacher. There are posts about perfect harmony we should emulate, or a call to copy an endless adaptability. These are the things that we might long for – but do not seem to be borne out in ecosystems where sea urchins demolish kelp forests, and the climate crisis reveals the limits of species to adjust. We are being called to see what we want (or feel we need) rather than what actually exists in the world around us.

This instinct to carve lessons from creation extends beyond the natural world to the work of human hands. The Japanese art of kintsugi, repairing broken pottery with gold, has become increasingly prevalent as a metaphor for healing; a beautiful idea but one that risks being stripped of its culture, and that has both limitations and dangers. In Sarah Perry’s novel, The Essex Serpent, Cora’s husband Michael masks his abuse by speaking in a romantic metaphor of his intention to break her down and mend her with gold, like the Japanese art in their hallway. But Cora is not a vase; she is woman. Michael’s breaking harms her. She only begins to repair after he is gone; it is messy, some parts seem irrevocably changed. I think of my own losses, and how healing is indeed available, but rarely as straightforward as putting the same pieces back together. To think it is so can hinder our restoration, and miss out on the transformation that may be possible. As the journalist Poorna Bell wrote after her husband’s death by suicide: “I was in some ways sadder, wiser, but also my existence was much bigger, more honest.”

We have a great capacity to learn – and we need it to survive. As writer Andy Crouch put it in his book, Culture Making: “a human baby is the strangest and most wonderful creature this world can offer. No other mammal emerges so helpless from the womb, utterly unable to cope with the opportunity and adversity of nature. Yet no other creature holds such limitless possibility… We are hard-wired for nothing but learning. All we begin with are possibilities.”

This ability to grow and understand and change is essential if we are to navigate the world. And in our encounters with this place, with brokenness and confusion, the instinct to make meaning, to tidy, to be able to point to something and say 'this is how we should be’ is a form of comfort. Maybe even control it. We are grappling with not just how to understand the world, but how to be in it.

If we are always looking for the lesson, we devalue nature by prizing it just for what it can give us.

Creation and creativity have much to teach us – they’re a testament to and the fruit of the imagination of God. But to prize them just for their lessons seems to fall into another form of extraction and to miss out on something else, something that may be a greater gift in this messy world: wonder.

Bees moving from flower to flower are not setting out on their mission with a side hustle of education for the human race. They are being their full bee selves. Nectar is necessary; this is how it is collected. Bees share knowledge about the good plants via a ‘waggle dance’. This is how the colony persists. It is not for my benefit (though it may encourage me to a moment of playfulness).

Writing this on my balcony, I pause when I see dozens of birds circling one thermal; a moving column of gulls and red kites that goes up and up and up. I could strive for a teachable moment (maybe something about co-existence?) but it feels not just unnecessary, but an interruption. In that moment, I was a human being in awe of birds riding the warm air; that feels like something full of beauty in itself. I worry that if we are always looking for the lesson, we devalue nature by prizing it just for what it can give us. And we miss out on the opportunities to marvel at creation itself.

And, in calling each other to be like other creatures, we accidentally dehumanise other people and ourselves. In the face of conflict, polarisation and disconnection, to contend for each other’s humanity feels vital. And to recognise our own humanness is to acknowledge our limitations. There are parts of nature currently beyond our comprehension. Birdsong holds complexity heard by the intended audience but we can only guess at its meaning. There is something to accepting the edges of our own understanding. Sometimes we touch on truths that seem to contradict or be in tension. Perhaps they are layers that we cannot intellectually fit together but that build up a fuller, richer story that resonates in our souls. Glimpsing something of the multifaceted wisdom and wonder of God himself – and that helps us to remember who we are. A particular type of creature: a human.

So, I won’t be a bee. I’ll keep trying to learn to be what I am: a particular human in a bigger community, world and story. Now, I’m off to admire the goldfinches, glinting in the sunshine.

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