A second look

31 May 2013 by Malcolm Campbell, posted in Biology

There are only two ways to live your life. One is as though nothing is a miracle. The other is as though everything is a miracle. Albert Einstein (1879-1955)

Every day we pass by the commonplace, the mundane. Common objects of apparently little, if any, consequence are scarcely considered. If they serve some passing purpose, we use them. If not, unless they are obstructing our path, we overlook them. Our lives are so populated with such seemingly trivial entities that to give them any time would certainly hinder our ability to do what we feel we need to get done.

And yet, to overlook the mundane deprives us of a deeper appreciation of the universe in which we reside, and our place in it.

There is great awe to be found by considering the trivial.

A bench brought me to this realisation.

The bench was an ordinary bench by any measure. The bench was the sort normally used at sporting matches, either for players or spectators to be seated. The bench comprised a wooden seat bolted to metal upright brackets, which were in turn supported by being bolted to a wooden footing. The seat itself was made of interlocked pieces of hardwood slats. The wood had been coated with some sort of lacquer, but time, use, and weather had worn much of this away. The metal brackets were made of aluminium, and had hard rubber feet. The seat was held to the brackets by bolts that had been set into counterbored holes in the wood.

In short, it was a rather commonplace bench. Commonplace, until one considered it in greater detail.

The wooden seat alone was a marvel. The hardwood slats owed their consistency to over 360 million years of evolution.  Over 360 million years ago, by the late Devonian, plants had discovered how to elaborate wood, a novel biocomposite that supported great growth – both girth and height. Woody growth enabled plants to occupy a greater diversity of niches; thereby promoting a stunning radiation of plants across terrestrial ecosystems.

The genesis of wood starts with photosynthesis. Photons born in solar nuclear reactions race at light speed from our Sun, making the 8.3 minute trip to Earth to power photosynthesis. Plants capture this solar energy and use it in the catalysis of a marriage of two simple molecules, carbon dioxide and water. Through this process, photosynthesis, the carbon is fixed into sugar, and oxygen liberated.

Importantly, water and carbon dioxide are not merely passively residing in leaves awaiting photosynthesis. For trees, their sunlight-capturing height advantage is offset by the significant challenge of gathering and transporting water from the soil up to the leaves where photosynthesis takes place. Trees contend with this challenge with roots that forage for water through directional growth, and a plumbing system that allows the transport of water to great heights against gravity’s pull.

Trees’ water transport system is based on the wood itself. Wood contains cells that function as phenomenal conduits for water transport. These cells form giant capillaries that support columns of water that run the height of the tree.  The properties of wood – particularly its rigidity – enable the cells to resist inward collapse from the compressive forces that arise from drawing a column of water from the ground to such great heights.

The pump that pulls water to the tree canopy is transpiration. The release of water vapour at the surface of leaves through transpiration is sufficient to draw the column of water from the roots to the leaves. Transpiration occurs through pores on the leaf surfaces, stomata, which are dynamically opened and closed so that the plant controls the rate of water release.

Stomata can be thought of as little mouths, which open and close as the need to release or retain water changes. Indeed, stomata consist of two lip-like cells, guard cells, which control the opening and closing of the stomata pore. The guard cells open the pore at appropriate times so as to create the transpiration pulling force required to suck water up to the leaves, while retaining enough water in the leaves for photosynthesis.

The analogy with a mouth applies to another aspect of stomata function. In addition to opening to release water, stomata also open to collect carbon dioxide for photosynthesis. Stomata are, in essence, the gatekeepers of photosynthesis and water movement in plants.

The sugar created by photosynthesis is transported to parts of the tree that have the capacity to make wood. Wood is made by specialised cells. Here, the sugars are converted to chemical precursors of wood.

Wood is a composite made of two main components, cellulose and lignin.

Cellulose is woven by cells by joining simple glucose units end-to-end in a long, linear polymer. The unique manner in which the glucose units are linked enables hydrogen bonding along the length of the polymer, which gives it great strength. This strength is reinforced by another polymer, lignin.

Lignin is a three-dimensional polymer that functions like a glue to hold cellulose in place. This greatly strengthens the composite, giving wood its hard properties. Lignin is also a complex, water-repellent polymer, which makes wood both resistant to degradation, and water proof.  It is difficult to imagine building a more resilient composite making use of simple, benign, natural materials.

The wooden seat of the bench arose, therefore, from the intricate interplay of solar radiation, lip-like cells, a stupendous plumbing system, sugar-generating catalysis, and the melding of two remarkable polymers. Stunning.

The metal brackets of the bench had no less an amazing origin.

The metal brackets were made of aluminium (also called aluminum depending on where you live). Aluminium is a metallic element. It’s lucky number 13 in the periodic table of the elements.

Aluminium was discovered in 1825 by the Danish chemist, Hans Christian Ørsted, who was the first to refine the element. Aluminium was originally named aluminum, after the Latin 'alumen' or 'alum', which literally means bitter salt. The name was submitted for publication by Sir Humphry Davy, whose English editors changed the name to aluminium so that it conformed with other elements like potassium and sodium.

Aluminium is the most abundant metal on Earth. It comprises 8.1% of the Earth’s crust. This said, it is never found there as a free element, due to its high reactivity with oxygen. Instead, aluminium is found as a compound with over 270 different minerals. The most common form of aluminium is in bauxite, a mixture of hydrated aluminum oxide (Al2O3·xH2O) and hydrated iron oxide (Fe2O3·xH2O).

Aluminium is a highly malleable metal, with a relatively low melting temperature of 667oC. Taking advantage of this feature, humans have combined aluminium with a variety of other elements, including copper, magnesium and silicon, to make alloys that are both flexible and strong. These features enabled aluminium to be pressed into shape specifically for the purpose of creating the brackets for the bench.

This, to me, is what makes the brackets most amazing. Sure, they are made of an incredible element, with remarkable features. But it is the application of human ingenuity that really warrants awe.

Think about it. Somewhere, at some point in time, someone thought about the design of a bench. They thought about how the pieces would all work together. Since the emergence of simple, single cells on this planet, over 4 billion years ago, evolution honed a species that could imagine and conjure entirely novel objects, generated from novel combinations of elements, involving the collective actions of many, many other members of the same species.

The company that made the bench, Queonto, seems to have gone out of business in 1985. It was only 5 years old. So, sometime between 1980 and 1985, a person pondered the creation of a bench.

Applying a brain with around 90 billion neurons, with neurotransmitters firing across trillions of synapses, a person imagined a three dimensional object. They captured their imaginings on paper – jointed wood, embossed brackets, threaded bolts sunk into counterbored holes – all of it. Their imaginings were passed on to engineers, people who would design tools to shape the components of the bench. Others were dispatched to mine and make alloy from the aluminium, to harvest trees and hew wood. Still others shaped the alloy and the wood so that they could be wedded. Finally, yet others assembled the components. Together, this collective made a bench whose origins lay in the firing of synapses. It is appealing to imagine that at the end of this process, the designer laid a hand on the finished product and said, “I thought of this”.

The bench found employment at a school. There it provided a resting place for countless students, athletes and spectators alike. It was a site for coaching, as well as intimate conversation. It served as a graffiti board to etch relationship statuses. It was walked upon, jumped upon, spilled on, painted. Once its indoor usefulness was expended, it found itself on a disused track, exposed to all manner of weather – everything that the seasons could throw at it.

In the end, the bench succumbed to the very elements that made it. Sun and rain, heat and cold – eventually these undermined the bench’s integrity. In the meantime, the bench served as a resting place for someone to sit and watch dogs play – to sit in quiet contemplation – contemplation that lead back to the bench, and the many “miracles” that lead to its existence, and now its passing.

Considered at greater depth, the bench was a miraculous fusion of natural and human ingenuity.

How many other mundane objects do we pass by every day that share such incredible origins, that have similar histories, that we merely pass by with hardly a glance? Perhaps they deserve a second look. How much richer our lives would be if we just stopped, sat, and marvelled at their existence.

Images: All photographs by Malcolm M. Campbell.

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6 Responses to “A second look”

  1. Lee Turnpenny Reply | Permalink

    Fabulous! (You're a 'glass-half-full' person, aren't you?)

    I once read, I think, that with the really tall trees, such as the giant redwoods, the combination of negative transpiration pressure + positive root pressure + capillarity forces still does not (mathematically) explain how water traverses such height. (But perhaps that's been solved...?)

    • Malcolm Campbell Reply | Permalink

      Thank you very much for the kind feedback, Lee! You are right, I am a glass-half-full person, indeed!
      In response to your question, Rob P. has provided a useful link. I hope it is helpful.

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