A Confusion of Names

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0:00:09 > 0:00:13For centuries, people regarded plants

0:00:13 > 0:00:17as solely the creation of God, and some still do.

0:00:17 > 0:00:20Their variety had no human order to it.

0:00:20 > 0:00:25Plants were here to be celebrated, not questioned.

0:00:25 > 0:00:31As a botanist, I understand how plants are grouped into species.

0:00:31 > 0:00:37And yet, 300 years ago, this simple concept was highly controversial.

0:00:39 > 0:00:44To question the order of nature was to question God himself.

0:00:46 > 0:00:48In the late 17th century,

0:00:48 > 0:00:53scientific investigation began to erode religious certainty.

0:00:53 > 0:01:00The new discipline of botany was thinking about plants in new ways.

0:01:01 > 0:01:06What botanists were looking for, and are still looking for,

0:01:06 > 0:01:09is how the plant world fits together,

0:01:09 > 0:01:13understanding what is related to what.

0:01:15 > 0:01:19Grouping plants is what we botanists call "classification".

0:01:19 > 0:01:23It's not about making life easier, though that would be nice,

0:01:23 > 0:01:27it's about revealing the natural order of the world.

0:01:33 > 0:01:37Classification of plants is the basis of the science of botany.

0:01:37 > 0:01:42Pioneering botanists really struggled to invent a system

0:01:42 > 0:01:47so that knowledge could be passed on to future generations

0:01:47 > 0:01:50And they began to glimpse a world

0:01:50 > 0:01:54where bigger, better, stronger plants could be created.

0:01:56 > 0:02:01For the first time, the study of plants rejected religious dogma

0:02:01 > 0:02:03and embraced science.

0:02:05 > 0:02:07Today, botany is at the forefront

0:02:07 > 0:02:11of advances that will affect all our lives.

0:02:11 > 0:02:16And how it got there is a tale of intrigue, of jealous rivalry

0:02:16 > 0:02:18and of flawed genius.

0:02:18 > 0:02:22It's the story of how science unlocked the secrets

0:02:22 > 0:02:27of what, for me, is our most precious resource - plants.

0:02:45 > 0:02:48This is the University of Oxford botanic garden.

0:02:48 > 0:02:52I should, at this point, declare an interest

0:02:52 > 0:02:54For 22 years, I've been director

0:02:54 > 0:02:59of the most compact, yet diverse, collection of plants in the world.

0:03:05 > 0:03:10I have the benefit of centuries of accumulated knowledge,

0:03:10 > 0:03:14because this is the oldest botanic garden in Britain.

0:03:14 > 0:03:21It was founded nearly 400 years ago to celebrate and encourage understanding of the plant kingdom.

0:03:32 > 0:03:34At its most basic level,

0:03:34 > 0:03:38botany enables us to distinguish between these berries.

0:03:38 > 0:03:42That's important because this is St John's wort,

0:03:42 > 0:03:44used by some to treat depression.

0:03:44 > 0:03:49This is deadly nightshade, which will kill you,

0:03:49 > 0:03:51and these are blackcurrants.

0:03:51 > 0:03:57Botany can also tell us which plants are related to each other.

0:03:58 > 0:04:03That may not sound important, but it's been known for decades

0:04:03 > 0:04:07that this yew tree can be used to treat breast cancer.

0:04:07 > 0:04:14So it was logical to look at plants related to it, to see if they also contained useful molecules.

0:04:14 > 0:04:18Sure enough, its cousin over there is being used to treat leukaemia.

0:04:22 > 0:04:28This one example shows how important it is to define and classify plants.

0:04:30 > 0:04:35The first major breakthrough in the classification of plants

0:04:35 > 0:04:40was made by a young man studying not here in Oxford, much as it pains me,

0:04:40 > 0:04:42but in Cambridge.

0:05:01 > 0:05:05John Ray is a name most people have never heard of.

0:05:05 > 0:05:10Yet, for me, he's one of the greatest naturalists ever.

0:05:10 > 0:05:12CAMERA CLICKS

0:05:12 > 0:05:17As a student at trinity college, and armed with nothing more

0:05:17 > 0:05:21than a hand lens and the personality of a 17th-century geek,

0:05:21 > 0:05:27Ray glimpsed something that no-one else had ever seen - a natural order.

0:05:33 > 0:05:38The 17th century was an exciting time to be a scientist.

0:05:38 > 0:05:42This was the era when Isaac Newton uncovered laws of physics.

0:05:42 > 0:05:46There were revolutions taking place in the world of science,

0:05:46 > 0:05:49and botany is one of them.

0:05:49 > 0:05:51CAMERA CLICKS

0:05:51 > 0:05:55John Ray's pioneering work on classification

0:05:55 > 0:06:01moved the study of plants away from superstition and towards science.

0:06:05 > 0:06:10Ray did what field botanists do today, went out into the field,

0:06:10 > 0:06:14collected plants and pressed them in his herbarium press,

0:06:14 > 0:06:16brought them home and observed them.

0:06:18 > 0:06:20The more he looked,

0:06:20 > 0:06:25the more he began to see a pattern in the plants he collected.

0:06:25 > 0:06:29This pattern would be his first great discovery.

0:06:29 > 0:06:33Ray would have gone out into the Cambridgeshire countryside

0:06:33 > 0:06:36and found purple loosestrife.

0:06:36 > 0:06:40Purple loosestrife vary in a number of ways - some are taller,

0:06:40 > 0:06:42some have paler flowers.

0:06:42 > 0:06:47Some people would have said these were fundamentally different.

0:06:47 > 0:06:52Ray said, "No. This is just variation.

0:06:52 > 0:06:59"You get different plants coming from seed that has been collected from the same plant."

0:06:59 > 0:07:04My children have different coloured eyes, different coloured hair.

0:07:04 > 0:07:09That doesn't mean they're a different species. Probably.

0:07:12 > 0:07:17He argued that plants can look different and be closely related.

0:07:17 > 0:07:23He'd recognised natural variation between plants, and he went further.

0:07:23 > 0:07:28John Ray realised that there is a set of characters

0:07:28 > 0:07:33that remain unique to a group of plants, in particular, the flowers.

0:07:33 > 0:07:37Inside those flowers, the seeds,

0:07:37 > 0:07:40the seed vessel

0:07:40 > 0:07:44and the outer parts of the flower, the sepals.

0:07:44 > 0:07:49These were the characteristics that didn't vary within a species.

0:07:49 > 0:07:52These could be used to define a species.

0:07:52 > 0:07:55It may seem a bit strange today,

0:07:55 > 0:07:59but before Ray, no-one knew what a species was,

0:07:59 > 0:08:01let alone how to identify one.

0:08:03 > 0:08:08For the first time, we had a clear definition of what was a species.

0:08:08 > 0:08:14Defining species in that way was a huge step forward for botanical science

0:08:14 > 0:08:18and was one of Ray's major contributions to botany.

0:08:20 > 0:08:22His progress was short-lived.

0:08:22 > 0:08:26Soon afterwards, Ray was kicked out of Cambridge.

0:08:26 > 0:08:31In 1660, the monarchy is restored following the death of Cromwell.

0:08:31 > 0:08:39On a point of principle, Ray refuses to swear a new oath of allegiance to King Charles II.

0:08:42 > 0:08:48Had he stayed at the university, he may well have become as famous

0:08:48 > 0:08:50as his contemporary, Isaac Newton.

0:08:50 > 0:08:55Instead, he left Cambridge and walked away into obscurity.

0:08:58 > 0:09:01He exchanged the cloisters of Cambridge

0:09:01 > 0:09:04for rooms in a house owned by one of his students.

0:09:04 > 0:09:08This is Middleton Hall in Staffordshire.

0:09:08 > 0:09:12It's here that Ray made his next discovery.

0:09:12 > 0:09:18He'd defined a species by those characteristics of plants that don't change.

0:09:18 > 0:09:21Now he wanted to go further,

0:09:21 > 0:09:26to see if species themselves can be organised and grouped.

0:09:26 > 0:09:30He wanted to know if they could be classified.

0:09:30 > 0:09:33When John Ray was living here at Middleton Hall,

0:09:33 > 0:09:37he was able to get on with what he did best,

0:09:37 > 0:09:40which was looking at plants.

0:09:40 > 0:09:43He would collect things, bring them back

0:09:43 > 0:09:49and...he saw things that other people missed.

0:09:49 > 0:09:53He turned his attention to looking at seeds.

0:09:53 > 0:09:57Flowering plants produce seeds. They all look quite different.

0:09:57 > 0:09:59But when you cut them open,

0:09:59 > 0:10:05Ray discovered that there seem to be two sorts of seeds.

0:10:05 > 0:10:11When you take a bean seed and cut it open, it splits into two.

0:10:11 > 0:10:15He then started cutting open other seeds.

0:10:15 > 0:10:20When he looked inside these seeds, he found that some, like this iris,

0:10:20 > 0:10:24didn't split nicely into two like that.

0:10:24 > 0:10:29There was just one structure in the middle.

0:10:29 > 0:10:32Ray had uncovered a fundamental split

0:10:32 > 0:10:34in the plant world.

0:10:36 > 0:10:41The first group that splits easily into two, he named the dicots,

0:10:41 > 0:10:44and the other, the monocots.

0:10:46 > 0:10:50As he looked at the structure of the plants in these two groups,

0:10:50 > 0:10:53he found five more significant differences -

0:10:53 > 0:10:58in the flowers, in the stems, the roots,

0:10:58 > 0:11:02the first leaves to emerge

0:11:02 > 0:11:05and the mature leaves.

0:11:05 > 0:11:10He realised that any further advances in classification

0:11:10 > 0:11:13could only come about by looking at the whole plant,

0:11:13 > 0:11:15all of its features, bar none.

0:11:21 > 0:11:24The man was a genius. He got it right.

0:11:24 > 0:11:29He created order out of the chaos that is nature.

0:11:29 > 0:11:32It's a testament to Ray's brilliance

0:11:32 > 0:11:35that his principles of classification

0:11:35 > 0:11:39are taught to this day, 350 years later.

0:11:39 > 0:11:44So, as chaplain to the household, was there a chapel here...?

0:11:44 > 0:11:50'These are the rooms where Ray began to crack the code of classification.

0:11:50 > 0:11:54'Today, they're looked after by Dr Ian Dillamore,

0:11:54 > 0:11:57'a trustee of Middleton Hall.

0:12:00 > 0:12:05'Although it's open to the public and you can learn about his work,

0:12:05 > 0:12:09'John Ray is hardly a household name.'

0:12:09 > 0:12:13He's not better known because he wrote his serious works in Latin

0:12:13 > 0:12:17and he could not afford to illustrate them.

0:12:17 > 0:12:21His humility in not pushing himself was very important as well.

0:12:21 > 0:12:27In the prefaces, he apologises for putting readers to the trouble

0:12:27 > 0:12:29of reading what he has to say!

0:12:29 > 0:12:31LAUGHING: That's terrific!

0:12:31 > 0:12:35"Does the world need another book like this?" he keeps asking.

0:12:35 > 0:12:39The answer is, "Desperately." There was no book like it.

0:12:39 > 0:12:44All of his books stand quite distinguished.

0:12:44 > 0:12:50The principles of classification that John Ray developed in the 17th century

0:12:50 > 0:12:52were largely ignored.

0:12:52 > 0:12:55The status quo was undisturbed.

0:12:55 > 0:12:59Botanists, farmers and gardeners had to struggle on

0:12:59 > 0:13:02with hearsay and superstition.

0:13:04 > 0:13:09Ray got the science right but the publicity hopelessly wrong.

0:13:09 > 0:13:12When you have a good idea, you need to...

0:13:12 > 0:13:15SHOUTS: ..shout it from the rooftops!

0:13:15 > 0:13:18That simply wasn't Ray's style.

0:13:21 > 0:13:24Modesty is a trait that could never be levelled

0:13:24 > 0:13:27at Sweden's most famous son of botany,

0:13:27 > 0:13:30the self-styled "prince of the plant kingdom", Carl Linnaeus.

0:13:30 > 0:13:35His approach was as far removed from that of John Ray as you could get.

0:13:35 > 0:13:39For Linnaeus, botany was all about sex!

0:13:43 > 0:13:47This is the student thesis of Carl Linnaeus.

0:13:47 > 0:13:52He called it "An introduction to the courtship of plants".

0:13:54 > 0:14:01When Linnaeus wrote about the sexuality of plants, it wasn't only novel, it was shocking.

0:14:01 > 0:14:05Because he described the reproductive biology of plants

0:14:05 > 0:14:11as if they were humans indulging in licentious and shocking sex.

0:14:14 > 0:14:17This was just the first deliberately shocking step

0:14:17 > 0:14:20in the career of botany's first celebrity,

0:14:20 > 0:14:25the showman and genius that was Carl Linnaeus.

0:14:29 > 0:14:32I've come to Uppsala in Sweden,

0:14:32 > 0:14:36where Linnaeus began his extraordinary career.

0:14:38 > 0:14:43Linnaeus just scraped into Uppsala University to read medicine.

0:14:43 > 0:14:47He was a difficult, under-achieving student

0:14:47 > 0:14:50and medicine was regarded as an inferior subject.

0:14:50 > 0:14:54But while here, Carl became an expert in anatomy.

0:14:55 > 0:14:58Plant anatomy.

0:15:02 > 0:15:08While his fellow students concerned themselves with the bloody workings of the human body,

0:15:08 > 0:15:11Linnaeus saw only flowers.

0:15:15 > 0:15:19Linnaeus had been obsessed with the sex lives of plants

0:15:19 > 0:15:23since he'd been shown their reproductive bits and pieces.

0:15:23 > 0:15:27So he would look at a plant like euphorbia

0:15:27 > 0:15:31and he would find a male part, called a stamen,

0:15:31 > 0:15:34and a female part referred to as the pistol,

0:15:34 > 0:15:38both present in the same structure.

0:15:38 > 0:15:42But not all plants have the same number of sexual parts.

0:15:42 > 0:15:46When he opened up this blue salvia, he found

0:15:46 > 0:15:49two males and one female.

0:15:49 > 0:15:53The males are the two with the yellow pollen on them.

0:15:53 > 0:15:58The female is the one with the blue tip.

0:15:58 > 0:16:03He looked in this penstemon, and when he looked inside this one,

0:16:03 > 0:16:09he discovered not one, not two, but four stamens!

0:16:09 > 0:16:12But still only one female.

0:16:12 > 0:16:16The more he studied, the more he became convinced

0:16:16 > 0:16:21that he'd found a way to classify the plant kingdom.

0:16:21 > 0:16:26He argued that nothing could be more fundamental to a plant's identity

0:16:26 > 0:16:28than its genitalia.

0:16:28 > 0:16:31He believed he could order the vast diversity of plants

0:16:31 > 0:16:34by their sexual parts alone.

0:16:45 > 0:16:49In the hallowed halls of learning across Europe,

0:16:49 > 0:16:54scientists were discovering the laws of their disciplines.

0:16:54 > 0:17:00But botany didn't have any, and now Linnaeus thought he'd found them.

0:17:00 > 0:17:07As he rather immodestly put it, "God created. Linnaeus classified."

0:17:13 > 0:17:18For five years, Linnaeus continued to study - identifying, counting,

0:17:18 > 0:17:21noting and describing the genitalia of plants.

0:17:24 > 0:17:27With his research completed,

0:17:27 > 0:17:29he was ready to publish.

0:17:31 > 0:17:35So here's Linnaeus's Systema Naturae,

0:17:35 > 0:17:38published in 1735.

0:17:38 > 0:17:41For a book that changed the world,

0:17:41 > 0:17:45it's...small, it's only 14 pages.

0:17:45 > 0:17:48I like to think of Linnaeus's work

0:17:48 > 0:17:52as like an 18th-century computer spreadsheet.

0:17:52 > 0:17:56The most simple flower is one that has just one stamen.

0:17:56 > 0:17:59Here we have those with one stamen.

0:17:59 > 0:18:02Then there are two boxes in that column,

0:18:02 > 0:18:07those with one female and those with two females.

0:18:07 > 0:18:11Then the next column boxes are those that have two males.

0:18:11 > 0:18:14All those plants only ever have one female.

0:18:14 > 0:18:17When you get into three stamens,

0:18:17 > 0:18:21there are flowers that have one, two or three females.

0:18:21 > 0:18:24It's beautifully neat and tidy.

0:18:24 > 0:18:29It works simply from the left-hand side starting with one stamen,

0:18:29 > 0:18:34right the way across, to where it's more than 20.

0:18:35 > 0:18:38Linnaeus knew if his system was to succeed,

0:18:38 > 0:18:41it had to be accepted in England,

0:18:41 > 0:18:46the most important and influential horticultural market in Europe.

0:18:46 > 0:18:50He began what can only be described as a marketing campaign.

0:18:50 > 0:18:54He sent advance copies of his Systema Naturae to the key players

0:18:54 > 0:18:56and he set sail for England.

0:19:15 > 0:19:17When Linnaeus arrives in London,

0:19:17 > 0:19:19he's not yet 30 years old.

0:19:19 > 0:19:23He has no money or friends in high places, he's shabbily dressed.

0:19:23 > 0:19:26He doesn't even speak any English.

0:19:26 > 0:19:31He carries his address in case he becomes lost or waylaid.

0:19:31 > 0:19:35All he had going for him was his incredible confidence.

0:19:39 > 0:19:44Soon after arriving in London, he headed for the Royal Society.

0:19:44 > 0:19:50He assumed he'd have no trouble persuading the great and the good of the scientific world

0:19:50 > 0:19:55of the significance of his Systema Naturae.

0:19:55 > 0:19:59He'd then have access to all the important men of the kingdom.

0:19:59 > 0:20:02He couldn't have been more wrong.

0:20:02 > 0:20:08The doors of the Royal Society were shut firmly in Linnaeus's face.

0:20:18 > 0:20:22His marketing campaign failed spectacularly.

0:20:22 > 0:20:27The preview copies of his sexual system for ordering nature caused uproar.

0:20:27 > 0:20:30Not because of the bold ideas,

0:20:30 > 0:20:34but because of the language Linnaeus used to express them.

0:20:34 > 0:20:38One critic condemned Linnaeus's system as "loathsome harlotry"

0:20:38 > 0:20:44because "it was like a tour round the bed chambers of prostitutes."

0:20:44 > 0:20:50In effect, our Carl had written the screenplay of a Swedish blue movie,

0:20:50 > 0:20:53and the English were deeply offended!

0:20:55 > 0:20:59None of which mattered to our young botanical voyeur.

0:20:59 > 0:21:04He was convinced he was right and everyone else was wrong.

0:21:07 > 0:21:11And anyway, he'd come to England to meet just one person -

0:21:11 > 0:21:15the current holder of the title Linnaeus coveted,

0:21:15 > 0:21:19that of the greatest horticultural authority in Europe.

0:21:23 > 0:21:26His name was Philip Miller.

0:21:32 > 0:21:34Miller was a diligent gardener

0:21:34 > 0:21:38and, like Linnaeus, a determined self-promoter.

0:21:38 > 0:21:41A clash of egos was inevitable.

0:21:44 > 0:21:50Miller started his career as a lowly florist in the flower markets of London,

0:21:50 > 0:21:55awash with new plants from around the world.

0:21:55 > 0:22:01The arrival of this new wealth of plants brought great opportunities.

0:22:02 > 0:22:07But it also came with its own problems.

0:22:07 > 0:22:12What was causing consternation was the names. Take this, for example.

0:22:12 > 0:22:16Known as American wisteria, Wisteria frutescens,

0:22:16 > 0:22:20but also known as Mr Catesby's new climber.

0:22:20 > 0:22:24Which is quaint, but it is not scientific.

0:22:26 > 0:22:30Every country had developed different names for its plants.

0:22:30 > 0:22:33These even varied from region to region.

0:22:33 > 0:22:37There were no universally agreed names.

0:22:37 > 0:22:40This made it impossible to share advice

0:22:40 > 0:22:44when you didn't know if you were talking about the same plant.

0:22:48 > 0:22:52Philip Miller spied the chance to make his name.

0:22:52 > 0:22:55He would put an end to this confusion

0:22:55 > 0:22:58by regulating the naming of plants.

0:22:58 > 0:23:03To do this, he founded the Society of Gardeners.

0:23:04 > 0:23:08Once a month they met at Newhall's coffee house in Chelsea

0:23:08 > 0:23:14to discuss and name the flowers, trees and shrubs flooding in from the New World.

0:23:15 > 0:23:22The purpose of the society was to compare such things as should be received from abroad

0:23:22 > 0:23:25with those already in the English gardens,

0:23:25 > 0:23:29and discover where the real differences, if any, lay.

0:23:32 > 0:23:35Philip Miller felt that their whole profession,

0:23:35 > 0:23:38the new science of botany, was in danger.

0:23:38 > 0:23:42He wrote, "All the sciences have each their proper language,

0:23:42 > 0:23:49"but botany alone has almost as many different languages as there are different authors."

0:23:53 > 0:23:57Miller believed that, as the self-appointed most talented,

0:23:57 > 0:24:01the Society of Gardeners would soon compile a catalogue

0:24:01 > 0:24:05of all the foreign species growing in English gardens.

0:24:07 > 0:24:09Sadly, the society collapsed,

0:24:09 > 0:24:13overwhelmed by the enormity of the task.

0:24:17 > 0:24:19But it made Miller's name.

0:24:19 > 0:24:26He was appointed head of the most prestigious botanic garden in London, the Chelsea Physic Garden.

0:24:32 > 0:24:34As he began his work,

0:24:34 > 0:24:37Miller, who was never short of confidence,

0:24:37 > 0:24:42promised that Chelsea would soon out-vie all other gardens in Europe.

0:24:42 > 0:24:44And he was probably right.

0:24:55 > 0:24:57In the 50 years Miller was here,

0:24:57 > 0:25:00he utterly transformed the garden.

0:25:00 > 0:25:04He was directly responsible for doubling

0:25:04 > 0:25:08the number of foreign species successfully grown in Britain.

0:25:11 > 0:25:13The purpose of a physic garden

0:25:13 > 0:25:17was to grow plants with medicinal properties.

0:25:17 > 0:25:19Miller went further.

0:25:19 > 0:25:22He developed it into a centre of economic botany,

0:25:22 > 0:25:27growing cotton and roots used in the dye industry.

0:25:27 > 0:25:32A lot of the plants here have the second name tinctorius,

0:25:32 > 0:25:35which implies that they were used as a dye.

0:25:35 > 0:25:42Here, for example, we've got dyer's weld, Roseda luteola.

0:25:42 > 0:25:45This here for a red dye.

0:25:45 > 0:25:49There's other dye plants here, like woad,

0:25:49 > 0:25:52now being used as a treatment for cancer.

0:25:54 > 0:25:57Now you've got dyes, you need something to dye.

0:25:57 > 0:26:01Here, lots of plants used for their fibres.

0:26:01 > 0:26:05We've got sisal, for example, for rope.

0:26:06 > 0:26:08These are used in Japan.

0:26:08 > 0:26:14And finally, one of the plants that changed the world, really. Cotton.

0:26:14 > 0:26:17Hard to imagine the history of America being the same,

0:26:17 > 0:26:22had it not been for the cultivation of cotton.

0:26:25 > 0:26:29'Daniel Pretlove is one of the gardeners here at Chelsea.

0:26:29 > 0:26:34'An aim of the garden is to keep it looking as it did in Miller's time.'

0:26:34 > 0:26:38We still keep here, the vegetable beds, the herbal beds,

0:26:38 > 0:26:43the pharmaceutical beds set out as Miller had them in his time.

0:26:43 > 0:26:46They were reinstalled about 15 years ago.

0:26:46 > 0:26:53He's a great person to have in your history, he's such a major figure in the history of English gardening.

0:26:53 > 0:26:57He was here for such a long time. He changed the face of horticulture.

0:26:59 > 0:27:02'Miller was an innovator.

0:27:02 > 0:27:06'To grow the more exotic species he designed glasshouses

0:27:06 > 0:27:10'with their own intricate heating systems.'

0:27:10 > 0:27:15- Miller had glasshouses. How did he heat them?- They were coal-fired.

0:27:15 > 0:27:20Did somebody have to stay up all night stoking the boilers?

0:27:20 > 0:27:22They usually had someone.

0:27:22 > 0:27:28Usually the under gardener, the apprentice, had to put out the fires.

0:27:28 > 0:27:36- Trainees today just don't know that they have such an easy time of it! - That's right.

0:27:40 > 0:27:44In his day, Philip Miller was regarded as the most distinguished

0:27:44 > 0:27:46and influential gardener in Britain.

0:27:46 > 0:27:50It wasn't simply for what he'd achieved at Chelsea.

0:27:50 > 0:27:52It was for what he'd written.

0:27:52 > 0:27:56Miller took the notes from the ill-fated Society of Gardeners

0:27:56 > 0:28:03and compiled the first comprehensive dictionary of gardening.

0:28:03 > 0:28:09Miller's book is this great bringing together of the knowledge of that time.

0:28:09 > 0:28:14He's gathering together names and horticultural practice

0:28:14 > 0:28:17and putting it in one place.

0:28:17 > 0:28:22For the first time, everything you needed to know about every plant

0:28:22 > 0:28:25found in an English garden was in one place.

0:28:25 > 0:28:29It became the standard work, the bible, if you like.

0:28:29 > 0:28:34Miller simply listed everything clearly and in alphabetical order.

0:28:34 > 0:28:37He made no attempt to classify.

0:28:39 > 0:28:42His dictionary, published in 1731,

0:28:42 > 0:28:46became THE reference work for gardeners around the world.

0:28:48 > 0:28:52All the names given to the same plant were listed together,

0:28:52 > 0:28:54eliminating confusion.

0:28:54 > 0:28:59The dictionary gathered more authority with every new edition.

0:29:00 > 0:29:04And it turned Philip Miller into a superstar.

0:29:05 > 0:29:09When you start on a new scientific venture

0:29:09 > 0:29:13you must gather together all that is known about your subject.

0:29:13 > 0:29:16That was Miller's great contribution.

0:29:16 > 0:29:22His dictionary brought order and focus to all the knowledge available at that time.

0:29:25 > 0:29:29His dictionary became an international best-seller.

0:29:29 > 0:29:36This is what brought Carl Linnaeus to Chelsea Physic Garden in 1736.

0:29:38 > 0:29:43Linnaeus wanted Miller to promote the sexual system of classification

0:29:43 > 0:29:47by including it in the next edition of the famous dictionary.

0:29:49 > 0:29:53But the meeting of the two egos was a frosty affair.

0:29:54 > 0:29:58Linnaeus, we know, was an opinionated chap.

0:29:58 > 0:30:00In Miller he had found his match.

0:30:00 > 0:30:05Miller dismissed Linnaeus's classification system.

0:30:05 > 0:30:10He predicted "that it will be of a very short duration".

0:30:10 > 0:30:13Linnaeus had hoped for Miller's support.

0:30:13 > 0:30:18Now he derided Miller's achievements as "mere plant collecting".

0:30:18 > 0:30:23This was the beginning of a life-long rivalry.

0:30:28 > 0:30:31So Linnaeus stared failure in the face,

0:30:31 > 0:30:37but there was one chink of light for the self-styled prince of botanists.

0:30:37 > 0:30:39Oxford.

0:30:52 > 0:30:55Linnaeus came here,

0:30:55 > 0:30:59to our botanic garden in Oxford, to see Johann Jacob Dillenius,

0:30:59 > 0:31:02Professor of Botany.

0:31:02 > 0:31:04He had read Linnaeus's book

0:31:04 > 0:31:07and had not been convinced by it.

0:31:07 > 0:31:12As Linnaeus demonstrated his vast knowledge of plants

0:31:12 > 0:31:16and the beautiful simplicity of his sexual classification system,

0:31:16 > 0:31:19the two became firm friends.

0:31:21 > 0:31:25They were inseparable during Linnaeus's time in Oxford,

0:31:25 > 0:31:29and they were to write to each other for the rest of their lives.

0:31:29 > 0:31:35When Linnaeus left, Dillenius begged him under tears and kisses to live and die with him.

0:31:35 > 0:31:38He offered to share his salary to keep him in Oxford.

0:31:40 > 0:31:46Linnaeus had saved face. With the University of Oxford ready to accept his classification system,

0:31:46 > 0:31:50he could return to Sweden with his head held high.

0:31:50 > 0:31:53Who needed Philip Miller?

0:32:01 > 0:32:03Linnaeus arrived back in Uppsala

0:32:03 > 0:32:08with an ambitious plan to transform the Swedish economy.

0:32:08 > 0:32:13His confidence in his own abilities knew no bounds.

0:32:13 > 0:32:16However, he did raise sufficient funds

0:32:16 > 0:32:20to establish a National Botanic Garden.

0:32:20 > 0:32:24And this is the result, the botanic garden at Uppsala,

0:32:24 > 0:32:30which Linnaeus had laid out according to his sexual system, as it still is today.

0:32:32 > 0:32:35The plants are set out in beds

0:32:35 > 0:32:39according to how many sexual parts they have.

0:32:48 > 0:32:52I've wanted to visit Linnaeus's botanic garden for many years

0:32:52 > 0:32:55and see his work first hand.

0:32:56 > 0:33:01Coming to Linnaeus's garden is a pilgrimage for any botanist.

0:33:01 > 0:33:05Seeing the plants laid out according to his sexual system

0:33:05 > 0:33:09really is a testament to the genius of the man

0:33:09 > 0:33:14and to his confidence that this was the system that people would adopt.

0:33:28 > 0:33:32Just six years after his arrival in England as a penniless upstart,

0:33:32 > 0:33:38Linnaeus was Professor of Botany at the university and the director of his own garden at Uppsala,

0:33:38 > 0:33:43where he settled into a career of continued research and teaching.

0:33:47 > 0:33:51Here he could have stood, master of all he surveyed.

0:33:56 > 0:34:00'He had status, wealth and a crowd of adoring pupils

0:34:00 > 0:34:04'who he used to take on lively botanical trails.

0:34:07 > 0:34:11'The original Linnaean trails have been reintroduced

0:34:11 > 0:34:15'by Dr Mariette Manktelow of Uppsala University.

0:34:17 > 0:34:21'I joined her for a spot of botanising.'

0:34:21 > 0:34:25He was a marvellous teacher. He was one of the best.

0:34:25 > 0:34:30He was very charismatic and people loved to listen to him.

0:34:30 > 0:34:33He really inspired his students.

0:34:33 > 0:34:35These excursions,

0:34:35 > 0:34:39- they weren't the subdued botanising that you would expect?- No.

0:34:39 > 0:34:44- They were fantastic. There could be 100 students...- Amazing!- ..singing.

0:34:44 > 0:34:47They stopped at his house and everybody shouted,

0:34:47 > 0:34:51"Hooray for Linnaeus!" They were very happy.

0:34:51 > 0:34:55- Word spread that this was how you learnt botany.- Yeah.

0:34:55 > 0:34:59He had hundreds of students coming with him in the 1740s.

0:34:59 > 0:35:08'It was on these trails that Linnaeus identified a significant weakness with botany at the time.

0:35:08 > 0:35:13'The names that were used for plants were very unwieldy.'

0:35:13 > 0:35:18On one of the journeys he made to Stockholm he found this trifolium.

0:35:18 > 0:35:21'For example, we came across this clover.

0:35:21 > 0:35:24'Its name in Linnaeus's time was...'

0:35:30 > 0:35:36Here we have one of those woodland plants that Linnaeus also saw here.

0:35:36 > 0:35:38This is viola.

0:35:38 > 0:35:43'For Linnaeus and his students, this viola's full title was...'

0:35:52 > 0:35:57'These were descriptions of every minute detail of the plant.

0:35:57 > 0:36:00'In this case, it translates as...'

0:36:06 > 0:36:13'To teach, even just write down, these foot-long names had become completely impractical.'

0:36:13 > 0:36:17How do you carry out field biology like this

0:36:17 > 0:36:21if the name takes 30 seconds to say?

0:36:28 > 0:36:33Linnaeus set out to find a neat and easy way for naming plants,

0:36:33 > 0:36:39just as he thought he had found a neat and easy way of classifying them.

0:36:41 > 0:36:46What Linnaeus realised was all a plant name had to do was designate.

0:36:46 > 0:36:48It did not need to describe.

0:36:48 > 0:36:52A universal language was needed to do this,

0:36:52 > 0:36:55and that is what Linnaeus gave us.

0:36:57 > 0:37:01He came up with a beautifully simple set of rules.

0:37:01 > 0:37:06He reduced the lengthy names to just two words.

0:37:06 > 0:37:10The first word is like a manufacturer's name.

0:37:10 > 0:37:13The second word...

0:37:13 > 0:37:17refers to the models of the things they make.

0:37:17 > 0:37:19So, take...

0:37:26 > 0:37:30..Becomes viola mirabilis.

0:37:30 > 0:37:36Rather easier to remember. Much quicker to write down. Very simple.

0:37:36 > 0:37:39Over the next two decades,

0:37:39 > 0:37:44Linnaeus applied his two-name system to over 7,700 plants.

0:37:44 > 0:37:50When he published them in his next best-seller, Species Plantarum,

0:37:50 > 0:37:54it was a giant step forward for science.

0:37:54 > 0:37:58Whereas Miller had listed all the names of every plant,

0:37:58 > 0:38:03Linnaeus had come up with a system which was simple and short.

0:38:03 > 0:38:05So this is a catalogue

0:38:05 > 0:38:09of every plant name that has ever been used.

0:38:09 > 0:38:14And each species has...

0:38:14 > 0:38:18all the names that have been used plus Linnaeus's new name,

0:38:18 > 0:38:22the short name, the two-word name.

0:38:22 > 0:38:27This really sets the precedent for standardisation of names.

0:38:27 > 0:38:32Without permanent names there can be no permanence of knowledge.

0:38:32 > 0:38:37One after another, botanists and gardeners around the world

0:38:37 > 0:38:41accepted the new two-name or binomial system, turning to Linnaeus

0:38:41 > 0:38:45for the final decisions on what plants should be called.

0:38:47 > 0:38:51With the exception, that is, of a certain Philip Miller.

0:38:51 > 0:38:58Miller did not approve, railing instead, that Linnaeus had "the vanity of being the law-giver".

0:38:58 > 0:39:02It was not until the eighth and last edition of Miller's dictionary

0:39:02 > 0:39:06that Linnaeus's binomial system was finally included.

0:39:10 > 0:39:13In his autobiography Linnaeus says

0:39:13 > 0:39:17that he did not think that the binomial system would be his legacy,

0:39:17 > 0:39:20but it was, and it's a big contribution.

0:39:20 > 0:39:23In fact, it's a colossal contribution.

0:39:23 > 0:39:28Thanks to Linnaeus, botanists around the world could now identify

0:39:28 > 0:39:30and classify plants,

0:39:30 > 0:39:34teach, correspond and advance their science easily,

0:39:34 > 0:39:38efficiently, coherently.

0:39:44 > 0:39:49Here in the botanic garden in Oxford, as elsewhere,

0:39:49 > 0:39:53we still use Linnaeus's binomial system.

0:39:53 > 0:39:58Some Linnaeus named after botanical heroes, thus immortalising them.

0:39:58 > 0:40:00But for his arch rival Philip Miller

0:40:00 > 0:40:03he had something else in mind.

0:40:07 > 0:40:10For Philip Miller, Linnaeus spitefully chose

0:40:10 > 0:40:15a rather weedy member of the daisy family.

0:40:17 > 0:40:21Linnaeus believed there should be a connection

0:40:21 > 0:40:23between the botanist and the plant.

0:40:23 > 0:40:29The outer stumpy petals of the Milleria flowers reputedly refer

0:40:29 > 0:40:31to Miller's plump figure.

0:40:31 > 0:40:37Now, Linnaeus has a reputation for being arrogant and a self-publicist.

0:40:37 > 0:40:41And yet the plant he chose to name after himself,

0:40:41 > 0:40:45the twin flower, or Linnaea borealis,

0:40:45 > 0:40:48is a sweet pretty little thing.

0:40:50 > 0:40:57Perhaps Linnaea borealis is a very rare example of Linnaean modesty.

0:40:57 > 0:41:00Maybe he was human after all.

0:41:01 > 0:41:06Linnaeus's naming method was very successful and survives to this day.

0:41:09 > 0:41:12The more botanists looked at his sexual system,

0:41:12 > 0:41:14the more flawed it appeared.

0:41:14 > 0:41:18There were inconsistencies and anomalies you can't have in science.

0:41:22 > 0:41:26If you follow Linnaeus's system, you look at a lily,

0:41:26 > 0:41:29it has six male parts, three female parts.

0:41:29 > 0:41:36If you look at a yucca, it has six male parts, three female parts.

0:41:36 > 0:41:41The same is true of butcher's broom. Same is true of asparagus.

0:41:41 > 0:41:48Then you look at these plants, and they are so totally different.

0:41:48 > 0:41:54The number of male and female parts can vary among different flowers

0:41:54 > 0:41:57on the same plant.

0:41:57 > 0:41:59It was not a reliable way to group plants.

0:41:59 > 0:42:05Through his obsession with plant genitalia and perhaps his arrogance,

0:42:05 > 0:42:09Linnaeus had ignored a fundamental flaw.

0:42:09 > 0:42:11His mistake was to focus

0:42:11 > 0:42:17on just one feature, the sexual organs of plants.

0:42:17 > 0:42:23As John Ray had warned, any classification system has to take into account the whole plant.

0:42:23 > 0:42:27As Linnaeus's system fell into disrepute,

0:42:27 > 0:42:34botanists began to rediscover the work of the long-forgotten John Ray.

0:42:36 > 0:42:42Amongst them was Philip Miller, who had the last laugh on his rival.

0:42:42 > 0:42:44He had stood firm

0:42:44 > 0:42:47against the juggernaut of Linnaeus's self-promotion.

0:42:47 > 0:42:51Chelsea Physic Garden never embraced the sexual system of classification.

0:42:54 > 0:42:59Without question, Miller was the outstanding gardener of his age,

0:42:59 > 0:43:03but that doesn't mean he was popular.

0:43:03 > 0:43:07Despite his fame, not a single portrait of Miller exists.

0:43:07 > 0:43:10Not even a sketch. Why?

0:43:10 > 0:43:16Because, like Linnaeus, he never underestimated his own ability,

0:43:16 > 0:43:19and he suffered fools not at all.

0:43:19 > 0:43:24So on his death, he left no friends to celebrate his achievements,

0:43:24 > 0:43:30but he left plenty of enemies who would rather forget he ever existed.

0:43:33 > 0:43:39The world of plants could be a brutal arena with colossal egos.

0:43:39 > 0:43:42It could also be a dangerous place

0:43:42 > 0:43:45if you wanted to push the boundaries.

0:43:46 > 0:43:50Britain was still a God-fearing society.

0:43:50 > 0:43:56The power of religious authorities remained a block on scientific advance.

0:43:56 > 0:44:02If you were smart, you'd carry out experiments away from prying eyes.

0:44:02 > 0:44:04OWL HOOTS

0:44:04 > 0:44:08In 1716, a man called Thomas Fairchild

0:44:08 > 0:44:11makes his way furtively to his garden.

0:44:15 > 0:44:20He carefully closes the door of his potting shed and sets to work.

0:44:22 > 0:44:28He wants to try an experiment that has never been done successfully.

0:44:30 > 0:44:33Thomas Fairchild was a successful nursery man.

0:44:33 > 0:44:38In Hoxton, north London, he sold not only British native species

0:44:38 > 0:44:40but exotic plants

0:44:40 > 0:44:44that people had sent him, but suppliers were unreliable.

0:44:44 > 0:44:49He decided to take nature into his own hands.

0:44:49 > 0:44:53Behind closed doors, Fairchild turned creator.

0:44:53 > 0:44:59He wasn't interested in classification, and he didn't want to improve an existing flower.

0:44:59 > 0:45:02He wanted to create a new plant

0:45:02 > 0:45:08so that he could sell blooms that his rivals didn't have.

0:45:08 > 0:45:13Fairchild was about to create an artificial hybrid flower,

0:45:13 > 0:45:17a plant that couldn't be found in nature.

0:45:19 > 0:45:24He had prepared two flowers, a carnation and a sweet william.

0:45:24 > 0:45:28He took male pollen from the sweet william...

0:45:31 > 0:45:36..and he placed it on the female part of the carnation.

0:45:39 > 0:45:41And then, he waited.

0:45:42 > 0:45:47He waited until the carnation produced seeds.

0:45:47 > 0:45:50Then he sowed them. This was the true test.

0:45:50 > 0:45:54When his hybrid seeds grew and burst into flower,

0:45:54 > 0:45:57he knew he'd succeeded.

0:45:57 > 0:45:59To dry and preserve his new plant,

0:45:59 > 0:46:04he cut the stem of the ruffled pink bloom and pressed it carefully

0:46:04 > 0:46:06between two sheets of paper.

0:46:10 > 0:46:12And this is the result.

0:46:12 > 0:46:16This simple specimen isn't much to look at,

0:46:16 > 0:46:19but for botanists like me, it's a milestone -

0:46:19 > 0:46:24the world's first scientifically created hybrid.

0:46:26 > 0:46:29But when he finally emerged, clutching his sample,

0:46:29 > 0:46:32it was not in triumph, but in dread.

0:46:40 > 0:46:43Fairchild knew that most of his contemporaries

0:46:43 > 0:46:48were still enthralled to the story of creation in the Bible.

0:46:48 > 0:46:53God had made all the species of plant and animal, and that was that.

0:46:55 > 0:46:57300 years ago, Thomas Fairchild

0:46:57 > 0:47:01thought he had "created" a new species.

0:47:01 > 0:47:06And his guilt was immense because he had cast doubt

0:47:06 > 0:47:08on the story of the creation.

0:47:08 > 0:47:13His reaction to assuage his guilt was to make a benefaction

0:47:13 > 0:47:17to this church in Shoreditch so that an annual sermon could be preached

0:47:17 > 0:47:20to glorify the work of creation.

0:47:20 > 0:47:26He knew how important his discovery was.

0:47:26 > 0:47:31He had made a new plant, and that should not have been possible.

0:47:34 > 0:47:40He knew that man's relationship with plants would never be the same again.

0:47:46 > 0:47:48It was nearly four years

0:47:48 > 0:47:52before Fairchild dared tell the world about his experiment.

0:47:52 > 0:47:59On 4 February 1720, he made his way anxiously to the headquarters of the Royal Society in London.

0:47:59 > 0:48:06He presented his pressed flower to the scientific world, fearful of the reaction he might receive.

0:48:09 > 0:48:14"The experiment by Mr Fairchild found a plant of a middle nature

0:48:14 > 0:48:18"between a sweet william and a carnation flower,

0:48:18 > 0:48:23"a specimen which produced no seed but is barren, like the mule."

0:48:27 > 0:48:29These are the minutes of the meeting

0:48:29 > 0:48:33when Fairchild came to the Royal Society.

0:48:33 > 0:48:35He really didn't need to worry.

0:48:35 > 0:48:38The members were able to see beyond the faded colours

0:48:38 > 0:48:43of this now famous exhibit, and realise the significance.

0:48:45 > 0:48:49The Fellows of the Royal Society were not so concerned with the Bible

0:48:49 > 0:48:53as excited by the possibilities that the hybrid presented.

0:48:53 > 0:48:55But there was a problem.

0:48:55 > 0:48:59Fairchild's hybrid could not produce seeds.

0:48:59 > 0:49:03It was sterile. Nobody knew why.

0:49:08 > 0:49:12For all the progress, the steps towards classification,

0:49:12 > 0:49:15and understanding the sex lives of plants,

0:49:15 > 0:49:20to the first plant dictionary and a universal naming system,

0:49:20 > 0:49:25still botanists could not answer this fundamental question.

0:49:25 > 0:49:27Why was Fairchild's mule sterile?

0:49:27 > 0:49:30What was the missing piece of the jigsaw

0:49:30 > 0:49:34that would enable scientists to create fertile hybrids,

0:49:34 > 0:49:38stronger crops, more efficient medicines?

0:49:40 > 0:49:46The missing link was an understanding of how different plant species evolved.

0:49:48 > 0:49:54This missing link arrived in the shape of Charles Darwin and his book on The Origin Of Species.

0:50:04 > 0:50:06Botany was a passion of Darwin's.

0:50:06 > 0:50:11He demonstrated that plants had the ability to adapt to surroundings

0:50:11 > 0:50:16and, as a result, can increase their chances of survival.

0:50:20 > 0:50:23He'd set sail in 1831 on board the HMS Beagle.

0:50:26 > 0:50:32The ship's naturalist, he was fascinated by the diversity of plant life in the southern hemisphere.

0:50:36 > 0:50:40Darwin saw that flowers which are pollinated by the wind

0:50:40 > 0:50:43have little colour.

0:50:43 > 0:50:48While those that need to attract insects are brightly coloured.

0:50:49 > 0:50:54For over a decade, he observed plants and carried out experiments.

0:50:54 > 0:50:58He understood that natural selection applied as much to plants

0:50:58 > 0:51:00as it did to animals.

0:51:02 > 0:51:08Darwin's theory of evolution, finally published in 1859,

0:51:08 > 0:51:13may have put the cat amongst the pigeons in religious circles.

0:51:13 > 0:51:20But for botanists, it was like manna from heaven, finding the Holy Grail, because it explained everything.

0:51:21 > 0:51:2619th-century botanists recognised the significance of Darwin's work

0:51:26 > 0:51:31on how and why plants evolved into different groups.

0:51:33 > 0:51:36In his notes for the book,

0:51:36 > 0:51:39Darwin uses this illustration.

0:51:39 > 0:51:41It's the metaphor of a tree,

0:51:41 > 0:51:45showing how species diverged as they evolved.

0:51:45 > 0:51:49Growing from a central trunk, some branches dying out,

0:51:49 > 0:51:51others sprouting further growth.

0:51:51 > 0:51:57The newest twigs and leaves far away from the roots but still connected.

0:51:59 > 0:52:02The Origin Of Species changed everything.

0:52:02 > 0:52:06Darwin explained why we CAN classify plants.

0:52:06 > 0:52:11The plants in a well-defined natural group share a common ancestor.

0:52:11 > 0:52:15He explained why plants with fewer things in common

0:52:15 > 0:52:17are more distantly related,

0:52:17 > 0:52:24and why plants that have a lot in common are more likely to produce fertile offspring.

0:52:31 > 0:52:33Botanists now understood

0:52:33 > 0:52:37why Fairchild's experiment 150 years earlier had failed.

0:52:39 > 0:52:42The plant he bred was sterile

0:52:42 > 0:52:45because the carnation and the sweet william

0:52:45 > 0:52:47come from two distinct species.

0:52:47 > 0:52:52They're not closely related enough to breed successfully.

0:52:52 > 0:52:56This understanding of the importance of classification

0:52:56 > 0:52:59underpins botanical science to this day.

0:53:07 > 0:53:14I've come to probably the most famous botanic garden in the world, Kew Gardens.

0:53:14 > 0:53:17It's where I trained as a gardener.

0:53:17 > 0:53:22The work begun by Miller, Linnaeus, Fairchild and John Ray

0:53:22 > 0:53:25continues here.

0:53:25 > 0:53:29Simple field lenses are supplemented by 21st-century tools

0:53:29 > 0:53:35such as scanning electron microscopes and DNA analysis.

0:53:35 > 0:53:39The work to define and classify plants

0:53:39 > 0:53:41is as vital as ever.

0:53:46 > 0:53:49One of the scientists, Professor Monique Simmonds,

0:53:49 > 0:53:54came across a plant in Ghana that was being used to treat malaria.

0:53:54 > 0:53:59She was curious to see if there was scientific basis for the treatment.

0:54:04 > 0:54:08The plant belongs to the same family as sage.

0:54:08 > 0:54:12The herbarium archive at Kew found 300 species in the same group,

0:54:12 > 0:54:1762 of which have also been used in traditional medicines.

0:54:23 > 0:54:26Professor Simmonds identified her specimen

0:54:26 > 0:54:29as Plectranthus barbatus...

0:54:30 > 0:54:33..and began a chemical analysis.

0:54:33 > 0:54:37She found a totally new anti-malarial compound.

0:54:39 > 0:54:46The active compounds that we're looking at appear to be in the hairs on the leaves.

0:54:46 > 0:54:51- Right.- And when you stress the plant, when you cut it back,

0:54:51 > 0:54:53the leaves that then regrow

0:54:53 > 0:55:00seem to have a higher concentration of the active compounds.

0:55:00 > 0:55:04That was encouraging, but was Plectranthus barbatus

0:55:04 > 0:55:08the best source of the anti-malarial compound?

0:55:08 > 0:55:13Could other related species produce more of the compound

0:55:13 > 0:55:16or a more potent version?

0:55:16 > 0:55:23Before we develop the project, we want to make sure that we've got the most effective species.

0:55:23 > 0:55:30If you look at the plants around us here, are the ones that are similar related,

0:55:30 > 0:55:34or are the ones that are diverse in style related?

0:55:34 > 0:55:41Molecular data can give us an insight into one species and its "near neighbours".

0:55:41 > 0:55:45Near neighbours most likely share a similar type of chemistry.

0:55:45 > 0:55:48The molecular data is the DNA fingerprinting?

0:55:48 > 0:55:53The DNA fingerprinting is what we're using as molecular data.

0:55:56 > 0:56:01The leaves of the Plectranthus are ground in a pestle and mortar,

0:56:01 > 0:56:07dipped in a hot bath mixed with chloroform, then shaken and spun.

0:56:07 > 0:56:10The sediment is removed, and when ethanol is added

0:56:10 > 0:56:14strands of DNA are visible, even to the naked eye.

0:56:20 > 0:56:24The sample is then frozen, along with another 40,000

0:56:24 > 0:56:30that make up an extraordinary database at Kew.

0:56:30 > 0:56:34By comparing this DNA with that of other species of Plectranthus,

0:56:34 > 0:56:39Professor Simmonds and the team came up with a precise family tree

0:56:39 > 0:56:45showing the nearest relatives to her original specimen.

0:56:47 > 0:56:54The DNA tree has enabled us to identify four or five other species

0:56:54 > 0:56:59that might contain similar or more active compounds,

0:56:59 > 0:57:02and that's the exciting part of the project.

0:57:02 > 0:57:05That's what we're putting our efforts into.

0:57:05 > 0:57:08We'd really like to find a new anti-malarial

0:57:08 > 0:57:12that could serve as a platform for development of a new drug.

0:57:12 > 0:57:15That would really be exciting.

0:57:15 > 0:57:21The malaria project demonstrates how valuable it is to understand the connections between plants.

0:57:21 > 0:57:26Incredible to think how far we've come since the early pioneers.

0:57:26 > 0:57:31Ray, with his hand lens, could only study plants from the outside.

0:57:31 > 0:57:35Now, with modern equipment, we can look from the inside outwards.

0:57:55 > 0:58:00The ability to harness and manipulate plants

0:58:00 > 0:58:04was made possible by the classification of the plant kingdom.

0:58:04 > 0:58:10The importance of botany and those early pioneers cannot be overstated.

0:58:10 > 0:58:13I know you'd expect me to say that, but it's true.

0:58:13 > 0:58:17'Next time on Botany: A Blooming History,

0:58:17 > 0:58:20'I'll look at how botanists wrestled with the question

0:58:20 > 0:58:25'of what plants do with water, sunlight and carbon dioxide,

0:58:25 > 0:58:29'the amazing process known as photosynthesis.'

0:58:50 > 0:58:53Subtitles by Red Bee Media Ltd

0:58:53 > 0:58:56E-mail subtitling@bbc.co.uk