Back to Lamarck?

“Did you know that acquired characteristics can be inherited?”

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Jean-Baptiste Lamarck

My daughter dropped that little bombshell on me one day after she came home from school.

“What kind of crap are they teaching you in that biology class of yours?” I grumbled.

“It’s called epigenetics,” she replied. “Look it up.”

I did. It blew my mind.

In previous posts, I wrote about Bernard Shaw’s attempt to found an evolution-based religion called Life Force Worship. Shaw’s ideas were based on the pre-Darwinian theories of Jean-Baptiste Lamarck. Here’s an admittedly crude and cartoonish rendition of the Lamarckian Story:

Once upon an extremely long-ago time, a certain hoofed animal ate all the leaves within easy reach. It then got into the habit of stretching its neck in order to eat leaves higher up. It passed along both the habit and an ever-so-slightly more elongated neck to its offspring. And lo, after untold generations of habit and inheritance, we now have giraffes in our midst.

Lamarckism eventually gave way to Charles Giraffe23Darwin’s theory of Natural Selection. Alas, according to this new idea, giraffes did not develop long necks solely through exercise and effort—by willing it, so to speak. Instead, giraffes lucky enough to be longer-necked managed to survive and procreate in the life-or-death struggle to reach higher leaves.

The process seemed (at least to thinkers like Shaw) to be intolerably random and mindless. Nevertheless, Lamarckism was relegated to the dustbin of defunct ideas—or so it was long thought.

Epigenetic_mechanismsI won’t try to explain how epigenetics works. I doubt that I’ll ever be able to wrap my own brain around it. The gist of it seems to be that, while our genes are pretty much inalterable, the expression of those genes is not. Moreover, acquired characteristics sometimes can be inherited. As Kara Rogers writes in Scientific American,

the implications so far suggest that our lifestyles and what we eat, drink, and breathe may directly affect the genetic health of our progeny.

What’s more, epigenetics may well offer possibilities for treating obesity, cancer, diabetes, addiction, aging, mental disorders, and all sorts of other bugbears of the human condition.

So has this new science given Lamarckism a new lease on life? There’s a lot of healthy skepticism out there. And I doubt that any serious epigeneticist is ready to claim that giraffes willed themselves into having longer necks. But epigenetics certainly looks like an inspiring plot point in the ever-evolving Story of life.

That Other Darwin

Here are a few lines to celebrate National Poetry Month

Organic life beneath the shoreless waves
Was born and nurs’d in ocean’s pearly caves;
First forms minute, unseen by spheric glass,
Move on the mud, or pierce the watery mass;
These, as successive generations bloom,
New powers acquire, and larger limbs assume;
Whence countless groups of vegetation spring,
And breathing realms of fin, and feet, and wing.

This poetic description of biological evolution was written by Darwin—not Charles Darwin, but his grandfather, Erasmus. And they appear in his poetic masterpiece, The Temple of Nature, posthumously published in 1803.

Erasmus Darwin formulated ideas about evolution (including Natural Selection) during the late eighteenth century, and proposed that all earthly life was descended from a “single living filament”—pretty much the orthodox view of today’s science. His grandson wouldn’t get around to publishing On the Origin of Species, now considered the founding text of evolutionary theory, until 1859.

I just finished re-reading Desmond King-Hele’s inspiring biography, Erasmus Darwin: A Life of Unequalled Achievement. It brought to mind my post of last year about proverbial foxes and hedgehogs. Remember the words of the ancient Greek poet Archilochus?

“The fox knows many things, but the hedgehog knows one big thing.”

If Charles Darwin was the consummate hedgehog, devoting decades at a crack to the single idea of Natural Selection, then Erasmus Darwin was the ultimate fox—a veritable überfox whose accomplishments ranged across all disciplines, all areas of knowledge. Consider just a smattering of facts about him:

He was longtime friends of Joseph Priestley, James Watt, Josiah Wedgewood, and most of the other the intellectual giants of his time. While he maintained a thirty-year friendship with Benjamin Franklin, the great Samuel Johnson was too daunted by Darwin’s genius to have much to do with him.

Erasmus was a philosopher-scientist of the first order, and a member of Britain’s Royal Society. He invented a copying machine and a voice synthesizer. He understood the electrical nature of nerve impulses before Luigi Galvani and Alessandro Volta performed their experiments with frogs’ legs and muscle contractions. He explained the formation of clouds, cold and warm fronts, and the basics of photosynthesis. He was a pioneer in understanding oxygen; he described how the heart and lungs oxygenize blood, and proposed that water was made up of oxygen and hydrogen.

He was a humanitarian who opposed slavery. As a physician, he gave free medical service to the poor. He was an early feminist who advocated education for girls and women, and he insisted on referring to our species as “humankind” instead of “mankind.” Although an Englishman, he was courageously pro-American during the Revolutionary War and supported the French Revolution. A committed freethinker, he advocated a secular morality based on compassion, and he felt touched and honored when the Pope condemned one of his books.

He was also more than a bit of a prophet. He proposed rockets powered by liquid fuel, a goal unrealized until the twentieth century. He dreamed up an internal combustion engine (one which would not pollute!) and designed a steering mechanism that would eventually be used in early automobiles. Some of his speculations are prescient of black holes, the Big Bang, and the DNA molecule.

All this is just the tip of the iceberg—and by the way, he had fascinating ideas about icebergs!

But here’s what I find most interesting. During much of the 1790s, Erasmus Darwin was considered the greatest living poet in the English language. His poetry and ideas were central to founding the Romantic movement, influencing Coleridge, WordsworthShelley, KeatsGoethe, and Sir Walter Scott. William Blake admired Darwin and designed engravings for his poetry. “Dr. Darwin” is cited (albeit erroneously) in the very first sentence of the preface to Mary Shelley’s Frankenstein. And unlike too many poets from his own age until today, he saw nothing incongruous or philistine about putting forth scientific ideas in verse.

What I like most about Erasmus Darwin is his kindness, good cheer, and optimism. Although, like his grandson, he understood that evolution was spurred by a ruthless struggle for survival, he believed that this struggle was ultimately aimed at “organic happiness” or “the Bliss of Being.” And so I’ll close with these joy-affirming lines from The Temple of Nature:

Shout round the globe, how Reproduction strives
With vanquish’d Death—and Happiness survives;
How Life increasing peoples every clime,
And young renascent Nature conquers Time.

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