It’s Not Easy Being Green

This is my second post on The Hidden Life of Trees, by Peter Wohlleben. It more or less covers chapters 5 through 8, though I also get sidetracked by discussions of Plato and anthropomorphism, topics (no doubt wisely) not covered in the book.

A Last Hurrah

Even without fire, extreme drought is deadly to trees. Their defenses run down and they become highly susceptible to insect attacks.

What’s surprising, however, is how they react. Under these pressures many bloom the following year. Wohlleben writes:

We know from times of high forest mortality that is usually the particularly battered individuals that burst into bloom. If they die, their genetic legacy might disappear, and so they probably want to reproduce right away to make sure it continues.

Even if it makes a kind of Darwinian sense, it seems oddly desperate or even poetic. It has a whole “one last hurrah” vibe to it. But perhaps I’m anthropomorphizing. If so, I’m in good company.

Arboreal Anthropomorphism

A friend of mine said, correctly I think, that Wohlleben tends to anthropomorphize in his book. When he attributes desire to a tree, he seems to be indicating that the tree is using emotion or logic to determine its next steps. In other words, he makes the tree sound as if it’s a human being.

Personally, however, I’m fine with this because trying to “write around” this issue would make his work read like a text book, replete with passive voice, wonky syntax and sterile language, all in an effort not to attribute human characteristics to trees. That strikes as me unnecessary for two reasons. First, we all know that trees aren’t human beings and that this bit of writerly shorthand is not necessarily to be taken literally.

Second, and perhaps more important, we still don’t understand trees. This is, in fact, one of the key themes of the book. We don’t know how the trees are able to do all the things they do. In many cases, we literally don’t know the degree to which they are and are not like us. In the absence of such knowledge, I don’t think we should get hung up on these issues. Save it for the scientific papers.

So, with those caveats in place, let’s anthropomorphize some more.

Tough Tree Love

Trees are very controlling parents. When a young tree takes root beneath the canopy of a parent tree, it is literally overshadowed for decades and often longer. Wohlleben notes that only 3% of available light gets through to the young tree, causing it to grow very, very slowly. From our perspective, this sounds like an extended juvenilization and a dysfunctional degree of tough love.

But it makes sense to the trees (or, at least, many species of them). Because of the slow growth of the juvenile trees, their “inner woody cells are tiny and contain almost no air” and this makes them more flexible, resilient, and resistant to fungus, insects and other threats. That which does not kill a tree apparently makes it stronger. Nietzsche would approve.

Plato’s Trees

You may remember that the Greek philosopher Plato had a theory of forms. This posits that only ideal forms encapsulate the true and essential nature of things whereas individual cases of those forms cannot live up that essential nature.

Referring to the theory of forms, Wikipedia explains, “We recognize a tree, for instance, even though its physical form may be most untree-like. The tree-like nature of a tree is therefore independent of its physical form.”

But maybe it’s the other way around. That is, maybe individual trees do not reflect the ideal tree in some imperfect form. Maybe the ideal tree stems from the very real needs of individual trees. Wohlleben writes:

This is what a mature, well-behaved deciduous tree looks like. It has a ramrod-straight trunk with a regular, orderly arrangement of wood fibers. The roots stretch out evenly in all directions and reach down into the earth under the tree….[T]here is a good reason for this ideal appearance: stability….Evenly formed trees absorb the shock of buffeting forces, using their shape to direct and divide these forces evenly throughout the structure.

Of course, not all trees wind up looking like the ideal, but they tend to have a better chance of a long and productive life if they do. So, evolution not only shapes the trees but our very ideal of trees–and perhaps even our inherited sense of what is and is not beautiful in the natural world.

The School of Hard Knots

Trees adapt. Or do they learn? What’s the difference?

I’m not going to take a stand on the question, but I will say that they definitely adapt and sure as heck seem to learn.

And its not just trees but other plant kin as well. Let’s start with mimosas. You may have experienced them before. They’re the plants that close their feathery little leaves when you touch them. I still remember the first time I encountered them because they seemed like some hybrid between a plant and animal. But, no, they’re just plants that react a bit more quickly to stimuli.

Dr. Monica Gagliano wanted to see if mimosas can learn, so she “designed an experiment where individual drops of water fell on the plants foliage at regular intervals.” At first, the leaves closed up whenever the drops hit, but then the plants determined that the water wasn’t going to harm them and so remained open even when droplets fell.

Is this learning? Maybe. But it gets more interesting. When Gagliano checked again weeks later, the plants somehow remembered their lesson from weeks before and didn’t close up when the droplets fell. If this isn’t learning, it’s hard to know what else to call it. Now how a brainless plant learns is not clear, but that’s for a different post.

For now, let’s go back to trees. It turns out some trees are spendthrifts and some are frugal when it comes to water. The spendthrifts are the ones with easy access to water and they use a whole lot of it. But they are also the ones hit hardest by droughts because they don’t know how to conserve. They can suffer badly as their wood dries out and this can result in major tears in their bark, opening them up to all kinds of ills such as insects and fungi.

But they can learn to be thriftier. Wohlleben writes that such tree often “takes the lesson to heart, and from then out it will stick with [a] new thrifty behavior, even when the ground has plenty of moisture–after all, you never know!”

So, can a tree be redeemed, having learned from it’s improvident ways? Perhaps so. Maybe there’s hope for all of us.

Featured image: Beech tree with frost crack bark damage, Stacklawhill. Rosser1954. https://commons.wikimedia.org/wiki/File:Beech_tree_with_frost_crack_bark_damage,_Stacklawhill,_North_Ayrshire.jpg

May the Forces Be with You


Making Up with Plato and Aristotle

In the second chapter of Reality Is Not What It Seems, Rovelli takes us on another millennia-spanning tour of physics. He starts by making up with Plato and Aristotle, whom he had previously seemed to denigrate by comparison with the great and yet savagely censored Democritus (see previous post).

Rovelli says that Aristotle, who invented the name of the physics discipline, deserves credit for describing the physical nature of the universe in a systematic if unquantified manner. He may not have understood the universe well by our standards, but what he wrote was coherent, rationale and served at as humanity’s best description of the physical universe for many centuries.

As for Plato, he championed mathematics (and, in particular, geometry) as a way of understanding the universe. Without mathematics, of course, we could not possibly have modern physics.

The Great Experimenter

Nonetheless, it took a long time before what we call experimental science emerged, according to Rovelli, who boldly states that “experimental science begins with Galileo” (aka, Galileo di Vincenzo Bonaiuti de’ Galilei, born February 15, 1564 and died January 8, 1642).

Once again, Rovelli seems to be simplifying in order to tell a clear, compelling and succinct story. I’m all in favor of that, but in reality there were probably a lot of experimenters before Galileo, even if they were not as systematic, brilliant and productive. For example, the Greek physicians Herophilos (335–280 BCE) and Erasistratus of Chios used experiments to further their medical research. Erasistratus repeatedly weighed a caged bird to determine its weight loss between feeding times.

But let’s go with Galileo as the first truly great experimenter. In a very small nutshell, he discovered that objects do not always fall at a constant speed and that, indeed, they pick up speed as they go: about 9.8 meters per second per second. This number comes up a little latter in history, speeding (so to speak) modern physics on its humanity-changing path. (By the way, the science fiction novel by Kim Stanley Robinson, Galileo’s Dream, goes into some detail about his experiments, insights and life; if you want to know more about Galileo without reading an actual biography, I’d recommend the book.)

Absurd Realities from Isaac

When Isaac Newton (born December 25, 1642 and died March 20, 1726) famously said, “If I have seen further it is by standing on the shoulders of giants,” he must have been thinking of Galileo as one of them.

Inspired by the moons of Jupiter (discovered by Galileo, of course), Newton conducted a thought experiment (a technique Einstein latter became especially famous for) in which he imagined a little moon orbiting the earth just above our highest mountain tops.

“Now,” writes Rovelli, “an object that orbits does not go straight: it continually changes direction, and a change of direction is an acceleration. The little moon accelerates toward the center of Earth. This acceleration is easy to compute. Newton makes the simple calculation and the result is … 9.8 meters per second per second! The same acceleration as in Galileo’s experiments for falling bodies on Earth.”

So Newton figures that the force that would cause the little moon to orbit around the Earth is the same one that Galileo measured for falling objects. In this way, he linked heavenly bodies with objects on Earth and came up with the modern idea of gravity, the first of the four basic forces so far identified by science.

But just because Newton came up with the idea and the math associated with it doesn’t mean he wasn’t baffled by it. Indeed, he thought the idea of one physical object (such as the Earth) acting on another physical object (such as the moon) via some distance and invisible thread of influence was “inconceivable” (even though he’d conceived it) and “is to me so great an Absurdity, that I believe no Man who has in physical Matters a competent Faculty of thinking, can ever fall into it.”

Except, of course, we all have “fallen” into it (did he recognize his pun?) for hundreds of years since. What’s more, we still don’t truly understand gravity, even if we have learned quite a bit more about it thanks to other great thinkers.

Mike and Jim’s Excellent Intellectual Adventure

Faraday the Astonishing Autodidact

Then, in the 1800s, two other British brainiacs came along and discovered another fundamental physical force that would change humanity, ultimately putting a powerful computer in the pockets of just about every angst-ridden teenager in the so-called developed world.

The two geniuses in question are Michael Faraday and James Clerk Maxwell, who are typically portrayed as the the original odd couple of electromagnetics. Faraday was an up-by-the-bootstraps scientist who grew up poor and not formally educated, yet he somehow sweet-talked his way into a lab assistant job with the Cornish chemist and inventor Humphry Davy. He was never trained in higher mathematics but, according to another of my favorite books on science history (Conquering the Electron: The Geniuses, Visionaries, Egomaniacs, and Scoundrels Who Built Our Electronic Age by Derek Cheung  and Eric Brach), he had a “uncanny intuition and a superhuman ability to visualize abstract objects, concepts and shapes.”

It was Faraday (born September 22, 1791 and died August 25, 1867) who basically created the first electrical motor, discovering that electrical energy could be directly converted into the kind of energy (that is, kinetic) that makes stuff move. (So, in theory, if there’d been no Faraday, we’d still be driving steam engines around and who knows what Elon Musk would be doing these days).

But, he was more than just a fantastic tinkerer. He came to the conclusion, in Rovelli’s words, that “there exists an entity diffused throughout space that is modified by electric and magnetic bodies and that, in turn, acts upon (pushes and pulls) the bodies. He calls these ‘lines of force.'” So, in essence, Faraday discovered fields!

Faraday created a number of iron filing diagrams in 1851 to demonstrate magnetic lines of force. Source: Royal Institution

Maxwell the Scottish Aristocrat

I love the little I know about James Clerk Maxwell (born June 13, 1831 and died November 5, 1879) because he seems almost god-like in his ability to crystalize the baffling universe into just a few, elegant equations. He was the Einstein of his day. In fact, without him, Einstein may never have crafted his theories of relativity at all. After all, Einstein’s special theory of relativity is often seen as owing its origin principally to Maxwell’s theory of electromagnetic fields.

Here’s what Maxwell achieved. After working 11 laborious years, he was able to embody all the electrical and magnetic principles into just four seemingly simple equations” (okay, there were 20 at first but they were later distilled by yet another Brit, Oliver Heaviside, whose name seems to pop directly out of a Dicken’s novel).

Rovelli says of the equations: “They describe an amazing number and range of phenomena. Almost everything we witness taking place, with the exception of gravity and little else, is well described in Maxwell equations.”

Perhaps most amazingly, Maxwell’s equations suggested that there would be other types of hitherto undiscovered waves aside from those teased out of nature by Faraday. In fact, it wasn’t too long after Maxwell’s death that radio waves were discovered, harnessed and transmitted. Here’s how Wikipedia reports it:

Radio waves were first predicted by mathematical work done in 1867 by Scottish mathematical physicist James Clerk Maxwell. His mathematical theory, now called Maxwell’s equations, predicted that a coupled electric and magnetic field could travel through space as an “electromagnetic wave”. Maxwell proposed that light consisted of electromagnetic waves of very short wavelength. In 1887, German physicist Heinrich Hertz demonstrated the reality of Maxwell’s electromagnetic waves by experimentally generating radio waves in his laboratory, showing that they exhibited the same wave properties as light: standing waves, refraction, diffraction, and polarization. Italian inventor Guglielmo Marconi developed the first practical radio transmitters and receivers around 1894–1895. He received the 1909 Nobel Prize in physics for his radio work. Radio communication began to be used commercially around 1900.

Maxwell never got to see all this because he died of stomach cancer at only the age of 48. If he had lived to be as old as Galileo, he would have seen Hertz generate radio waves, Marconi develop the first practical radio transmitters and receivers, and Einstein publish his special theory of relativity.

I so wish that the young Einstein could have met the old Maxwell, just as the young Maxwell met, interviewed and learned from the old Faraday. Yet life isn’t always fair like that, even for the truly great ones.

Feel the Forces, Luke

At this point in our scientific story, Galileo and Newton have discovered and quantified gravity while Faraday and Maxwell have done the same for electromagnetism. (That last sentence is an oversimplication, but let’s go with it.) Regardless of the names, humanity has learned to better understand and increasingly harness these two forces, not to mention the strong and weak forces discovered later. The forces were already there, of course, but understanding how to manipulate them has brought power that would have been viewed as god-like to people in the past.

In this sense, we are all like Luke Skywalker in the Star Wars universe, except the Forces are genuine. With them have come wonders, of course, but also more dangers. As fun as they might be, I don’t think our cinematic space operas can hold a candle to the narrative in which Forces-wielding humanity finds itself.

The Rise of New Networks

 A network is a group or system of interconnected people or things. Without networks of thinkers who communicate ideas over time, often via the written word, we would have have no real understanding of electromagnetism or the technologies based on that understanding.

These networks of ideas led to the rise of technologically mediated networks, which led to scientific ideas being spread across the world at the speed of light. This is where we are today, our radio waves not only spanning the globe but expanding well beyond it, perhaps one day washing up on alien shores light years away, maybe even reaching the stars of the Reticulum constellation itself.

The Reticulum Constellation. Author: IAU and Sky & Telescope magazine (Roger Sinnott & Rick Fienberg)
Featured image is VFPt dipoles electric from author Geek3. For more information, go to https://en.wikipedia.org/wiki/File:VFPt_dipoles_electric.svg