Darwin's Grandpa and the Art of Sex Appeal
Charles Darwin was stumped by peacocks. According to his theory of evolution, some creatures were better equipped to survive in their particular environment than others. It explained a lot - but it didn't explain the peacock's brightly coloured tail feathers, which were extravagant and cumbersome. Surely such plumage made it harder for peacocks to survive?
It so happens that the life of Darwin's own grandfather offered clues to the puzzle of the peacock's tail - if only he'd known to look there...
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Charles Darwin hated peacocks.
The sight of a feather in a peacock's tail, he said.
Whenever I gaze at it, it makes me sick.
But what had peacocks ever done to Charles Darwin?
For years, Darwin had been working out the details of his theory of evolution.
At the core of that theory was a simple but powerful insight.
Some creatures are better equipped than others to survive in their particular environment and they get to pass on their characteristics to the next generation.
Darwin called it natural selection and it explained a lot but not everything.
Look around in nature and you'll see plenty of things that don't seem to help with survival.
The peacock's tail, for example, with its long, brightly coloured feathers.
Surely having to lug around such cumbersome plumage must make it harder for peacocks to survive.
Wouldn't a peacock with a lighter, shorter tail be better able to run away from predators?
And yet, evolution had produced the peacock's tail.
How?
Every time Darwin saw a peacock, it painfully reminded him that he hadn't fully worked out the details of his theory.
And in the English countryside in the 1860s, Charles Darwin must have seen peacocks rather often.
They were popular with the landed gentry.
Charles was a country gentleman himself.
Where could Darwin turn for inspiration to solve his peacock problem?
Perhaps to the writings of others.
It's Charles whose name we associate with evolution today.
But many earlier thinkers had speculated along similar lines.
Chief among them was Darwin's own grandfather, the larger-than-life Erasmus Darwin, who had died before Charles was born.
Erasmus was enormously fat, gross and corpulent, said one unkind obituarist.
His features were coarse, he was rather clumsy and slovenly, and frequently walked with his tongue hanging out of his mouth.
What he lacked in conventional standards for good looks, though, Erasmus made up for in charm.
He attracted two beautiful wives and fathered 14 children, two of them with a third woman, between the marriages.
Erasmus made his living as a doctor, dabbled as an inventor, and won fame as a poet and a writer, including on evolution.
Would it be too bold to imagine, wrote Erasmus, that all warm-blooded animals have arisen from one living living filament?
That's impressive for the 1700s, long before anyone conceived of DNA.
As it happens, there was one particular aspect of Charles Darwin's grandfather's life that might have helped Charles figure out the peacock's tale.
But this is a story...
about how answers aren't always found in the most obvious places to look.
I'm Tim Harford, and you're listening to Cautionary Tales.
Josiah Wedgwood was born in seventeen thirty in the village of Burslem in the English Midlands.
The region was known for pottery from its local clay soils.
Josiah's father was a potter, but not a successful one.
His wares were low-priced and low-quality, his profit margins slim.
While other branches of the Wedgwood family had done well for themselves, Josiah's side were the poor relations.
Josiah was the youngest child of eleven.
Five of his older siblings died of smallpox.
Those who lived went to work in the family workshop as soon as they were able.
First, they shoveled clay into a kind of mill.
A horse walked in circles, turning a shaft that pummeled the clay with metal blades until it was ready to throw onto the potter's wheel, dip in a glaze, and bake in the brick oven.
It was hard physical work.
As a boy, Josiah too got smallpox.
It seemed for a while that he wasn't going to make it.
He lay in bed, weak and delirious, his body covered in pustules.
At last, the fever broke, the skin scabbed over.
But part of Josiah never really recovered from the illness, his right knee.
He hobbled back to the workshop and tried to find ways he could make himself useful while sitting down, resting his leg on a stool.
It wasn't easy.
But times were changing.
Some other local potters were starting to experiment with new techniques and ingredients to make new designs and coloured glazes.
Bowls that looked like tortoiseshell, teapots shaped like a cauliflower or pineapple.
Josiah found a job he could manage despite his painful leg.
He discovered that he loved to experiment.
A new shade of green, a vibrant orange-yellow, a more visually pleasing pineapple teapot.
By the age of 30, Josiah had set up on his own.
Every evening after work, he'd sit in his kitchen and mix together some new combination of metals and minerals, salts and enamels to glaze his wares.
He carefully recorded the results in a leather-bound notebook.
Experiment number 406.
This seems to separate, part is run thin like water, and is a good color, says one entry.
Experiment number 408, much the same, but less of the exuded watery part.
Every experiment was systematic.
Vary one ingredient, hold the others constant, and see how it changed the outcome.
Experiment number 409.
Rather better.
Josiah was trying to solve a problem that frustrated every potter at the time.
When they tried to make white-coloured wares, they always had a browny-yellow tinge.
And then...
Experiment number 411.
A good white glaze.
Josiah's new white plates were like nothing else on the market.
He could print on them, verses and pictures.
Business began to boom.
Josiah hired new workers.
He expanded into a second workshop.
And he finally felt successful enough to propose to the love of his life.
Sally was his cousin, from the wealthy branch of the Wedgwood family.
They had been smitten with each other for years.
But Sally's father, a successful banker, had always been sniffy about his only daughter marrying a potter.
He wanted Josiah to make him financial guarantees.
Exasperated, Josiah told a friend, I have gone through a long series of bargain-making of settlements, reversions, provisions, etc., etc.
It was mortifying, he said, to have to negotiate marriage like just another business deal.
If it were up to him and Sally, they could settle the whole affair in three lines and so many minutes.
Sally put her foot down.
She was nearly 30.
She'd never wanted anyone else, and her father relented.
Josiah was soon gushing in another letter to his friend.
They were two married lovers as happy as this world can make them.
Sally joined Josiah in the kitchen every night, mixing chemicals, glazing pots, and filling notebooks.
He'd taught her his code.
She helped him make more fashionable products that caught the attention of high society, 150 miles away in London.
An order came in that Josiah could barely have dreamed of, a tea service for the Queen of England, Queen Charlotte, the wife of Mad King George III.
Josiah's business could hardly be going better.
His right leg, though, was giving him more and more trouble.
On a badly rutted road, he'd fallen from his horse.
The pain was constant now, and his trusted doctor said there was only one thing for it.
That leg would have to come off.
The doctor?
Erasmus Darwin
Erasmus Darwin was born in 1731, a year after Josiah.
His career as a doctor got off to a shaky start.
His first patient, a man who'd been stabbed in a drunken brawl, died.
He got no other patients.
After a couple of months, he gave up and moved 40 miles to another town to try for a fresh start.
This time, his first patient was a young man from a wealthy family whose doctor had told them that his illness was incurable.
In desperation, The young man's mother called on the new doctor in town and asked for a second opinion.
Was there nothing Erasmus could do?
In truth, there wasn't much choice of treatments in the 1700s.
Erasmus later wrote down his prescriptions for a range of conditions.
For anorexia, for instance, opium, half a grain twice a day.
For impotence?
A grain of opium before bed.
Epilepsy?
Opium.
A grain every half hour.
Gallstones?
Tetanus?
You guessed it.
History doesn't record what Erasmus gave the young man whose doctor had given up on him.
Perhaps it was opium.
But whether or not Erasmus had anything to do with it, the patient made a miraculous recovery, and his family recommended Erasmus to everyone.
Soon Erasmus was making friends among the great and the good of the Industrial Revolution, treating their illnesses and sending them ideas for inventions.
Some didn't work out, like the horizontal windmill.
Others did, like a clever new steering mechanism for carriages.
He didn't bother to patent it, he just wanted to make his own journeys safer.
Erasmus had to travel a lot to see his patients, and the roads were terrible.
His idea for the steering mechanism was good enough to last.
Over a century later, it was the standard in the early car industry.
In his early 30s, Erasmus heard from an up-and-coming potter from the other side of the county.
Josiah Wedgwood was lobbying to raise funds for a canal.
It was hard to get his fragile goods to distant cities on the pothold roads, Josiah explained.
No matter how much straw he packed them in, something always got smashed.
Erasmus was well respected.
Would he support the campaign?
He would.
Erasmus threw himself into the cause, writing a long pamphlet on the benefits of inland waterways.
He became close friends with Josiah and doctor to the Wedgwood family.
Erasmus recommended a surgeon to take care of Josiah's troublesome leg.
The amputation was risky.
No antibiotics in the 1760s and fearful.
No anesthetic either.
Erasmus prescribed opium.
Josiah sat in a chair at home in a drug-induced haze while his wife Sally waited anxiously in the next room with their little daughter Susanna.
The surgeon redded his sore.
Cautionary Tales will be back after the break.
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You're listening to a cautionary tale about Charles Darwin.
and how he struggled to understand how the peacock's tail could have evolved when it seemed so obviously to hinder survival.
We'll come back to Charles and his peacock problem later on, but I promise that Charles might have better understood the peacock's tale if only he'd paid more attention to his own grandfather's life.
So let's get back to that life, where we left it.
Erasmus Darwin anxiously watched over his friend Josiah Wedgwood.
Josiah was off his head on opium, his right right leg a stump wrapped in bandages.
Ever the hard-nosed businessman, Josiah would have been happy to know his employees were getting on with a job.
A letter survives from the Midlands Workshop to the London showroom.
Sir, Mr.
Wedgwood has this day had his leg taken off.
and is as well as can be expected after such an execution.
Mr.
Horne's goods are packed in one crate for the warehouse.
Josiah's leg healed well.
He commissioned a craftsman to make him a wooden prosthetic with joints that moved and a foot that could wear a shoe and stocking.
Josiah worked hard on his tea service for the Queen.
The request was specific.
A complete set of tea things with a gold ground and raised flowers upon it in green.
Josiah knew how to do green glazes, but gold?
He had some gold leaf sent up from London and tried to work out how to burn it onto his smooth, ivory-white plates.
He was mortified to find it does not look so well as I expected.
He consulted books with arcane knowledge that might help or might not.
Mix the gold leaf with virgin honey.
Add resin, asphaltum and lead, boil, strain through a flannel.
Night after night, Josiah depleted his stocks of gold until at last he was happy.
He sent off the tea set and waited nervously.
Then he received an invitation to Buckingham Palace.
Josiah travelled to London, dressed up in his best scarlet waistcoat and blue velvet jacket, and treated himself to a brand new wig.
At the palace, Queen Charlotte told Josiah how much all her guests had been impressed with her new tea service.
She wanted to give Josiah a title, Potter to Her Majesty.
It was an honour.
And a marketing godsend.
Josiah promptly paid for announcements in the newspapers.
He also left the palace with Charlotte's blessing to make more of the same design.
and market them as queenswear.
Orders flooded in.
Josiah took on a business partner and drew up plans for a big new factory.
It is really amazing, Josiah mused to his partner, how rapidly the use of Queensware has spread almost over the whole globe and how universally it is liked.
Then Josiah asked himself, why?
How much of this general estimation is owing to the mode of its introduction?
And how much to its real utility and beauty?
We should be a good deal interested in the answer to that question, he said, because if a royal or noble introduction be as necessary as real elegance and beauty, then the manufacturer should bestow as much pains and expense on the former as the latter.
Josiah now had an open door into London's high society.
That's what happens when you're you're Potter to Her Majesty.
He sought out the aristocratic trendsetters.
What were they excited by?
The answer turned out to be antique vases, currently being brought back from the excavation of Pompeii.
What if Josiah could produce new vases in a similar style?
He went back to his workshop to experiment.
Forget Potter to Her Majesty, he playfully told his business partner.
He was going to be Vase Maker General to the universe.
There remained the problem of transporting those fragile vases from Josiah's new factory to the rest of the universe.
But the new canal that Josiah had lobbied for was finally being built.
And just like in Pompeii, some unexpected things were being excavated.
Josiah was fascinated to be shown a prodigious rib with the backbone of a monstrous-sized fish.
It had to be the whale that swallowed Jonah, the canal diggers said.
Other long-buried remains were even more mysterious.
Josiah thought Erasmus might be interested, so he sent them off.
Erasmus had no idea what he was looking at, so he made a joke of it.
The bone seems to be the third vertebra of a camel, he wrote back.
The horn must have been that of a Patagonian ox.
But beneath the jokes, Erasmus was intrigued.
These long-dead creatures that once roamed the English Midlands were unlike anything alive today.
How did species change through the ages?
Erasmus began to think,
but also decided to keep his thoughts to himself.
Everyone thought that God created species just as they were.
If he openly doubted that, he'd scandalize the devout among his patients.
He couldn't afford to risk the income.
Erasmus had a growing family to support, and his wife was becoming more and more unwell, with violent pains in her side and fits of delirium.
Nothing Erasmus tried was any help, except the opium to ease the pain, until, one day,
the dear partner of all the cares and pleasures of my life ceased to be ill, Erasmus wrote, and I felt myself alone in the world.
When Erasmus became a widower, his youngest son Robert was just four years old.
Josiah Wedgwood's new Pompeii-themed vases were a huge success.
Vases for the mantelpieces, vases as candle holders, vases for potpourri.
They exceed the ancients, said one impressed aristocrat in beauty and variety.
But success brought problems.
Josiah was investing so much to expand production, his cash flow became stretched.
Where should he cut back?
Josiah embarked on an exercise of what we'd now call management accounting.
It didn't have a name then, as nobody did it.
He wanted to understand how much profit each line brought in, when you apportioned wages, materials, coal for the kilns, and so on.
I'm puzzling my brains, he wrote to his partner.
But he figured it out.
Josiah was a pioneer beyond accountancy.
In marketing his new vases, he instinctively hit on two ideas that wouldn't be given names for over a century.
One idea was conspicuous consumption.
A few wealthy aristocrats would pay a high price to be among the first to buy a new design of vase.
They could show off both their money and their good taste.
Josiah gave his London showroom manager strict instructions when the first samples of a new product arrived.
Do not keep them open in the rooms, he said.
Show them only to people of fashion.
He defined his target market.
That sort of customers who can afford to pay for anything they like.
The second idea Josiah instinctively understood is now known as the trickle-down theory of fashion.
When a high-status person shows off something new, others try to copy them.
We see it today with wasteful fast fashion in the clothing industry.
A new designer look debuts on the catwalk.
A few weeks later, high street stores are selling cheaper look-alikes.
Here's how Josiah described the process.
The great people have had their vases in their palaces long enough for them to be seen and admired by the middling class of people, he wrote to his business partner.
The middling people would probably buy quantities of them at a reduced price.
Josiah's marketing strategy fit perfectly with what he'd discovered from his accounting exercise.
It cost a lot to figure out how to make something new, but then he could easily churn out replicas.
That would eventually cause the item to fall out of fashion, and Josiah knew it.
Our customers will not much longer be content with Queensware, he wrote a few years after after its launch, it now being rendered vulgar and common everywhere.
But that was fine.
It simply created demand for another novelty.
It always seemed to be ladies who drove new fashions, Josiah noticed.
He studied the trends in the leading female salons and never launched a product without his wife Sally's approval.
He also kept in mind his lesson that new products benefited from a noble introduction.
When he made a new flowerpot, for example, he suggested to his partner, Suppose you present the Duchess of Devonshire with a set and beg leave to call them Devonshire Flowerpots.
The Duchess of Devonshire was quite the social trendsetter, much like her great, great, great grandniece, Princess Diana.
Wedgwood's Devonshire flowerpots flew off the shelves.
Make something new, charge a high price, sell cheaper copies to the mass market, rinse and repeat.
Josiah became very rich.
Erasmus brought in a teenage governess to look after his children when his wife died.
Before long, he'd had two more daughters with her.
Then, he fell madly in love with the young wife of an elderly aristocratic patient.
He bombarded her with love poems.
Understandably, perhaps, the old husband decided to get himself a different doctor.
But he died anyway.
Erasmus married his widow, who'd inherited a sizable income.
They had seven more children together.
and folded the two young daughters of the governess into their blended family.
Erasmus' new wife encouraged him to publish his thoughts about evolution, among other things.
He was growing older.
He didn't need to worry so much about money anymore.
And if his writings caused a scandal, who cares?
Cautionary Tales will be back after the break.
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As Josiah Wedgwood became richer and more famous, his experiments became more ambitious.
I want to astonish the world, he wrote to his business partner, for I hate piddling, you know.
Josiah came up with a brand new way of colouring pottery.
Not by adding a glaze, but by infusing colour into the clay itself.
A distinctive shade of pale blue became synonymous with the Wedgwood name.
He made teapots and vases, with tasteful decorations in white relief, and medallions with the profiles of famous people.
By the late 1780s, Josiah and Erasmus were both approaching sixty.
Josiah launched a product that became a best-seller, a medallion depicting a black African slave, in chains, inscribed with the words, Am I not a man and a brother?
Josiah gave the prophets to the cause of abolishing slavery.
The medallion, said one campaigner, had an effect equal to that of the best written pamphlet.
Erasmus, meanwhile, transformed almost overnight from an obscure provincial doctor into one of the most famous writers in the land.
His first first publication was a poem, The Loves of the Plants.
In rhyming couplets, Erasmus combined an explanation of sexual reproduction in plant species with risque allusions to human relationships.
The poem is all flushed cheeks and seductive smiles, while the footnotes read like popular science.
It sounds like it shouldn't work, but apparently it did.
The most delicious poem on earth, said one famous critic.
The author is a great poet.
The follow-up poem was an even bigger success and even more unlikely.
In a single poem, with 80,000 words of explanatory footnotes, Erasmus deals with everything from astronomy to geology to the workings of steam engines, an artistic interpretation of his friend Josiah's latest vase, and a polemic against his country's role in the slave trade, inspired by Josiah's medallion.
The poor fettered slave, on bended knee, from Britain's sons imploring to be free.
By now, Erasmus' daughters with the governess were grown up.
Erasmus started a school for girls and put them in charge.
He wrote, A plan for the conduct of female education, ahead of its time for the 1790s when any kind of education for girls was a niche idea.
Some of his other books haven't aged as well, such as his textbook on medicine, which took nearly 800 pages to leave the strong impression that whatever your ailment, you may as well try
opium.
He finally published his thoughts on evolution, too.
Would it be too bold to imagine that all warm-blooded animals have arisen from one living filament?
Too bold?
It was for many readers.
These godless musings proved just as controversial as Erasmus had feared.
And for all that his living filament sounds startlingly prescient, Erasmus couldn't yet explain convincingly how evolution worked.
That would have to wait a couple of generations.
Charles Darwin read everything his grandfather wrote about evolution, but he was reluctant to cite Erasmus in his own work.
He seems to have been embarrassed by Erasmus' libertine lifestyle and unashamed enjoyment of sex.
Charles Darwin was a product of his era, the Victorian era, prudish and straight-laced.
In our present state of of society, wrote Charles, it may seem a strange fact that my grandfather's practice as a physician should not have suffered by his openly bringing up illegitimate children.
As for the popular acclaim for Erasmus' racy poems, well, that was quite incomprehensible to Charles.
Just like Erasmus, Charles dithered for years before before publishing his ideas on evolution, fearful of the backlash they might cause.
Remember Charles' great insight about natural selection.
Creatures that survive would pass on their characteristics to the next generation.
But the peacock's cumbersome tail seemed to hinder survival, not help it.
So how had it evolved?
The answer, Charles realised, starts with the insight that survival isn't enough.
To pass on your characteristics to the next generation, you need not only to survive, but to attract a mate.
In his private writing, Charles began to work out another strand to his theory, sexual selection.
If peahens chose to mate with peacocks with the most magnificent tails, then magnificent tails will be passed on to their offspring.
Charles was thinking along the right lines, but when it came to going public with his theory, Charles knew he had a problem.
In prudish, patriarchal Victorian society, nobody would want to believe that sex was a powerful force in shaping nature.
Even worse, female choice about who to have sex with?
Today, that idea is uncontroversial, but but as Evelyn Richards argues in her book, Darwin and the Making of Sexual Selection, to male Victorian scientists, it was almost unthinkable.
That's why the sight of a peacock made Charles feel so sick.
He knew he'd need some brilliantly persuasive arguments to have his idea taken seriously, but he failed to find them.
When Charles eventually published his theory of sexual selection, it was ridiculed, widely ignored, and quickly forgotten.
For a hundred years, it languished in intellectual obscurity.
Perhaps Charles could have made a more convincing case if he had had access to insights from modern biology.
One intellectual breakthrough came in the 1970s.
The handicap principle.
To Charles and his critics, it seemed like an obvious weakness in his theory that lugging around a massive tail surely makes survival harder.
The handicap principle turns that objection on its head.
It says, the peacock's tail evolved precisely because it hinders survival.
The peacock is showing off to peahens.
Look how fit and strong I am.
I can grow this magnificent tail and still outrun any predators.
Josiah Wedgwood would have understood this idea instinctively because it so closely mirrors another idea he anticipated, conspicuous consumption.
Remember how Josiah defined his target market for his expensive new vases.
That sort of customers who could afford to pay for anything they like.
Josiah knew some of his customers wanted to say something much like the peacock.
Look how wealthy I am.
I can buy Wedgwood's latest vase and still afford to live in luxury.
If only this analogy had occurred to Charles Darwin, he might have been less sickened by the peacock's tail.
He might have realised that hindering survival could be a powerful feature of his sexual selection theory, not a troublesome bug.
But that wasn't the only insight Charles was lacking.
When Charles published his theory, his critics scorned the implication that peahens must have a human-like ability to appreciate beauty.
It seemed like a stretch, and biologists now say sexual selection can work without it.
Peahens didn't need to evaluate the objective ideal of beauty, if there is such a thing.
They only needed to be able to spot the distinguishing features of the highest status peacocks.
Once again, Josiah Wedgwood would have had no trouble grasping that idea.
Remember what he once asked himself about the success of queenswear?
How much of this general estimation is owing to the mode of its introduction and how much to its real utility and beauty?
Josiah knew that people might buy queenswear, even if they themselves didn't find it beautiful, simply to boost their own status by associating themselves with the queen.
Biologists now see sexual selection as being about signals.
Peacocks, for example, signaling their genetic fitness through their tail.
In much the same way, we humans send signals about ourselves with our purchasing decisions.
We signal our wealth, our taste, our understanding of the latest trends.
Even our virtue.
Josiah, with his anti-slavery medallion, understood that too.
I told you that Charles Darwin might have found the answer to the peacock puzzle in the life of his grandfather.
But I didn't mean Erasmus Darwin.
I meant his other grandfather, Josiah Wedgwood.
In the winter of 1794, Josiah became ill.
His friend Erasmus prescribed everything he could think of, but nothing could work because Josiah had cancer of the jaw.
He died, aged 64.
The following year, his daughter Susanna married Erasmus' son, Robert.
Susanna Wedgwood and Robert Darwin had six children, including a boy called Charles.
While Charles grew up to share one grandfather's fascination with evolution, he didn't share the other grandfather's fascination with pottery.
We are degenerate descendants of old Josiah W., Charles wrote to a friend, for we have not a bit of prettyware in the house.
Prettyware.
You can almost hear the condescension.
Yet perhaps if Charles had studied his grandfather's prettyware business, the peacock's tale might not have puzzled him so much.
He might have noticed that peacocks showing off their tails are much like Josiah's customers showing off their their vases.
The clues were right there in Charles's family history, just
not where he'd thought to look.
This episode relied on biographies such as Josiah Wedgwood Entrepreneur to the Enlightenment by Brian Dolan and Tristram Hunt's The Radical Potter.
For a full list of sources see the show notes at TimHarford.com
Cautionary Tales is written by me, Tim Harford, with Andrew Wright.
The show is produced by Alice Fiennes with Marilyn Rust.
The sound design and original music are the work of Pascal Wise.
Sarah Nix edited the scripts.
Cautionary Tales features the voice talents of Ben Crowe, Melanie Gutteridge, Stella Harford, Gemma Saunders and Rufus Wright.
The show wouldn't have been possible without the work of Jacob Weisberg, Ryan Dilley, Greta Cohn, Eric Sandler, Carrie Brody, Christina Sullivan, Kira Posey and Owen Miller.
Cautionary Tales is a production of Pushkin Industries.
It's recorded at Wardore Studios in London by Tom Berry.
If you like the show, please remember to share, rate and review.
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And if you want to hear the show ad-free, sign up to Pushkin Plus on the show page on Apple Podcasts or at pushkin.fm slash plus.
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