History of plant science

Among the histories and commentaries on botany can be listed those of E.F.H. Meyer (1854), J. Sachs (1865), R.J. Harvey-Gibson (1919), E. Hawks (1928) and H.S. Reid (1942). For more contemporary accounts there are the excellent syntheses by Englishman A.G. Morton (1981) and American E.L. Greene (1983).

There is now a clear need for a new historical synthesis that includes scientific developments post-1950 . . . on the one hand the various developments and new disciplines emerging out of ecology and the global environmental movement and, on the other, the advances coming out of evolutionary biology, molecular biology, and gene technology.

The topic of plant science must include at least: an account of the men and women who have made an impact on the subject; the formal institutions that have promoted its interests; the impact of the science on the world; the place of the subject within the changing social, economic, and environmental context. Some of these topics are treated separately on this site.

This article here is a brief introduction and overview of the topic: it draws heavily on the Morton history, also the Wikipedia article History of Botany for which I was the major author – see that article for additional referencing.

For an account of Theophrastus’s life and work see Theophrastus. For a chronological account of the people contributing to plant science see People of plant science and a list of plant people of Australia (not just those associated with plant science). For an examination of the notion of plant science see plant science and for a summary of early Plant literature.

Introduction – History of Plant Science

A series of articles on the history of plant science examines the history of plant study by first looking critically at what we mean by ‘plant science’. Is plant science in some way a special and unique way of investigating plants that is different from any other form of plant study?

Before moving chronologically through the history of plant study, I first give a brief overview of the long-term changes that have occurred in the relationship between plants and people, and the way that plant study has changed over time as social organization has become more complex, technology more advanced, and societies more interconnected. This is a broad-brush overview of the changing character of plant study as it occurred during the historical transition from Natura, to Agraria, Industria, and Informatia.

This theme is then further explored in a second article that examines the changing social roles of people who were regarded as having special plant knowledge – people we can call plant practitioners: the social precursors to modern-day plant scientists. It examines the accumulation of plant knowledge by these plant practitioners, the institutions where they worked, and the historical circumstances that they faced.

The study of plants

Plants are an integral part of our daily lives – of the food we eat, the materials we use, and the oxygen in the air we breathe . . . so they are important to all of us. In this sense we are all students of plants.

Hunter-gatherers knew far more than us about the plants that grew around them . . . they knew which of them could be eaten, used as medicine, or fashioned into tools and structural materials: they knew where useful plants grew, as well as their names, how they would change with the seasons and respond to changing environmental conditions. This forager collective learning was acquired by careful observation combined with trial and error – in principle, hardly different from the empirical method of experiment and observation. So, were hunter-gatherers plant scientists?

Science

This question is addressed in more detail in two other articles: ‘What is science?’ and ‘The philosophy of plant science?’ However, for the purposes of this article two aspects of the activity we call ‘science’ will be emphasized: first, its claim to be a form of universal knowledge and, second, its progress by means of category refinement.

Universal knowledge

Science, is a body of knowledge that is open to challenge and improvement by anyone who can provide compelling empirical evidence. Its predictive capacity and technological by-products (like smartphones, televisions, and space rockets) are powerful demonstration of its application and importance for human lives.

Before 1600 Chinese, Indian, and European plant knowledge was comparable: expressed crudely it consisted of empirical descriptive knowledge documented in herbals that described plants in sufficient detail as to ascertain their medicinal properties. In both East and West these herbals were derived from sources dating back into antiquity. In the West the best known sources were Hippocrates, Theophrastus, and Dioscorides: in China it was the Han Dynasty writers. But with the European Scientific Revolution and Renaissance all this changed as, stimulated by the flood of plants into Europe from distant lands during the Ages of Discovery and Enlightenment, there began a meticulous systematization of the world of plants – their nomenclature, description, and classification. This was the beginning of modern taxonomy formalized by scholars like Englishman John Ray but developed by Linnaeus into a procedural methodology that eventually proved acceptable to the European botanical community.

This descriptive Western science was then transformed by the introduction of new technologies such as the microscope and other improvements in instrumentation that extended what was achievable with the unaided biological senses alone. By 1700 a discipline called botany was well established in Europe and it was considered different from (or in addition to) the previous similar forms plant knowledge present in both Europe and in China. A community of botanists in Europe were developing a commonly-accepted system of ‘scientific’ nomenclature and classification that was supplementary to the common names and utilitarian classifications that had existed before. The new study included herbaria for dried plants, botanic gardens for living plant collections and research botanists, and modern technology that initiated a new era of intense experimentation, coupled with advances in other subjects, most notably the chemistry that would unlock many of the mysteries of plant physiology.A key ingredient of ‘scientific’ knowledge is its universal application – its attempt to derive conclusions that are valid, regardless of circumstance. This contrasts with assertions made in accordance with social and religious tradition, dogma and ideology, charismatic individuals, and so on: science tries to be ‘objective’ and, in taking a disinterested or detached stance, gains the support of independent thinkers.

In developing the while respect for scientific knowledge derives from the social affirmation of the work of the community of scientists.

With the rigorous application of reason to find the most effective solutions to practical problems, collective scientific knowledge has accumulated, over time, by building on past successes.

One major development has been the extension of our biologically given senses and capacities through the use of increasingly sophisticated technology (e.g. microscopes, telescopes, electron microscopes, particle accelerators, computers, gene sequencers). Indeed, as globalization has advanced – the spread of Western science and technology, especially medicine, to southern and eastern hemispheres – gradually science has been accepted as a reliable source of collective learning about the physical world. This has been a long process that, from the point of view of the geographic dispersion of plant science, did not fully arrive in Asia in its Western form until the second decade of the 20th century.

Names, classification, terminology
One example of the universality of science is the use of scientific names for organisms. The use of a scientific (universal) name for a plant is a very powerful practice as it fixes the understanding of a particular kind of plant across cultures, bringing with it internationally accepted traditions of nomenclature and classification. In so doing it avoids confusion by providing consensual and precise information about the plant and an accepted means of future amendment. These principles also apply to the use of a ‘universal’ terminology for plant structures and processes.

The scientific description of plants is officially recognized as beginning with Linnaeus’s Species Plantarum of 1753. This is taken as the starting point for plant names by international agreement in what was, formerly, the International Code of Botanical Nomenclature. Plants were, of course, described before that time but as ‘phrase names’ which were simply short descriptions of the plant. The great strength of Linnaeus’s work was its systematic approach: it provided a standardised method of presenting plant names in extended lists. One of his accepted conventions was the use of a ‘binomial’, a two-word unique identifier for any plant. Linnaeus had not invented the binomial but he universalised its use.

Describing a plant involves two parties – the plant collector and the plant describer. Today these parties are often the same person but in the early days of Australia this was rarely the case. Collectors came from all walks of life. Sometimes they were a botanist but they may have been botanical bounty hunters, say, or perhaps gardeners or Aboriginals assisting explorers on land or sea.

A full formal botanical name today consists of the Latin binomial (generally in italics) followed by a standardized abbreviation of the person who first described it and a reference to the place where they published the description. Latin was the universal (western) language of scholarship at this time so it provided an effective means of communication between scientists.

The plant often known as Old Man Banksia, Banksia serrata, was first collected at Botany Bay on 29 April 1770, by Sir Joseph Banks and Daniel Solander, naturalists on the British vessel HMS Endeavour during Lieutenant (later Captain) James Cook’s first voyage to the Pacific Ocean. A species description was not published until April 1782, when Carolus Linnaeus the Younger (Linnaeus’s son) described the first four Banksia species in his Supplementum Plantarum. So we have:

Banksia serrata L.f. Supplementum Plantarum 1782

L.f. is the standardised abbreviation for ‘Linnaeus fils’ – the Latin for ‘son of Linnaeus’.

Category refinement

All plant knowledge began as locally shared knowledge. Over time, generally applicable plant knowledge was exchanged as part of trade and other forms of social interaction. In this way, with the improvement of transport and communication systems, knowledge in general became more geographically dispersed.

Though practical plant know-how had obvious benefits it was the spiritual, religious, and medicinal ‘powers’ of plants that appear to have captured the imaginations of humans of Natura. Collective learning underwent a major advance with the invention of writing which facilitated the storage and improvement of plant learning shared by larger groups of people.

As written, then printed and electronic plant knowledge – its categories, principles, theories, terminology etc. – has expanded, so the study of plants has been sub-divided into manageable-sized new disciplines with a major proliferation beginning in the 19th century as, supported by social and technological advances in Europe, descriptive botany was supplemented by subjects related to plant development, reproduction, physiology, and ecology.

One useful characteristic of science is the progressive refinement of the categories we used to describe the natural world, using experiment and observation to improve the categories we use. Science has made such dramatic progress as a form of collective learning that the categories devised in ancient times now appear crude. For example, the distinction between plants and animals, that we readily accept today, was not obvious to humans of antiquity. The first record of this distinction is attributed to philosopher-physician Empedocles of Akragas in Sicily (c. 494 – c. 434 , fl. 444–443 BCE) who is best remembered for his unification of the natural world under the four fundamental elements of earth, air, fire and water interacting through the forces of attraction and repulsion (love and strife). He also anticipated evolutionary theory by suggesting a process of selection of those organisms better adapted to their environments.^[18]

The first philosopher to study plants exclusively appears to have been Menestor of Sybaris in Italy (fl. c. 400 BCE), probably a Pythagorean, whose books are now lost, but quoted in ancient literature.

He was interested in the physiology of plants, particularly in what determines fruit-bearing or its failure and the time of budding or fruiting, and the reason for the deciduous or evergreen habit and for the ability of plants to grow in definite kinds of soil or climate, as well as in those properties of plants, such as taste or flammability, which made them useful to man – all problems of practical bearing.^[19]

Clearly by the time Aristotle and Theophrastus divided their studies between animals (Aristotle) and plants (Theophrastus), the distinction was accepted at the Lyceum.

The writings of Democritus, known to contain commentary on plants, are sadly lost.^[19]

But before investigating the study of plants in more detail, we can overview the topic by looking at the historical evolution of the role of plant practitioner and the places where these plant specialists worked.

What, then, distinguished the science of antiquity and that of today was not some special ‘scientific method’ but the increasing sophistication, complexity, and social integration of ideas as enhanced by rapidly advancing technologies.

Evolution of plant study

Earlier articles emphasized the way the human relationship to plants has been determined by the way plants, as an energy source, have influenced the nature of social organization. During the hunter-gatherer Natura phase wild plants provided the food energy that sustained all life. Through the sedentary and urban phase of Agraria it was cultivated plants that provided food energy. In Industria, to the food energy of cultivated plants was added the energy of fossil fuels that powered the machinery, technology, transport, and communication that accelerated social complexity and globalization, while Informatia has seen the advent of the Anthropocene requiring the management of the environmental impacts of a globally integrated community, most notably through the use of renewable energy sources.

Did the character of plant study change in tandem with these four phases of social organization?

Four phases can be discerned in the history of plant study, each phase emphasizing a particular aspect of the relationship between plants and humans. Phase 1, corresponding with the period of Natura, was a time when plants were viewed largely in terms of their utility. Though they were a vital source of food, plants and their preparation as food were generally treated as lesser ‘womens work’ with the men hunting game. However, it was the mediation of religious and spiritual treatment of ailments of various kinds that gained social status for those who possessed these skills. The emphasis on medicinal utility – the management of medicine, magic, and the spirit world – is characteristic of Natura, continuing with a more formally ritualized and codified religious form during Agraria and beyond.

With the advent of urban communities and writing (a major boost to collective learning) came a broad transition from animism to polytheism and monotheism controlled by a class of priests and scribes (scholars). They were familiar with the means of communication with the gods and their lives were dedicated to the spiritual life of their communities, together with the production and interpretation of legal, economic, sacred, and medicinal texts. Here was a new educated class of society controlling critical social knowledge that could be passed on in a written form as a supplement to the former oral tradition.

Phase 1 – Plant medicine

Plants in relation to humans
The first phase, which persisted into modernity, was about plant utility – concerned with plant use as food, materials, and medicines. In spite of the daily need for plant-based food it was the medicinal use of plants that acquired special significance. Plant powers (medicinal properties) were regarded as a manifestation of the supernatural and they could quickly change human lives for better or worse. The manipulation of these powers required mediators who possessed the special (often secret) knowledge of how to release these powers. Then there was also the role of the bearer of plant wisdom in mediating between the human and spirit worlds. A crude lineage can then be drawn between the shaman/medicine man, priest/scribe, apothecary/physician, academic/plant scientist.

Phase 2 – Botany

Plants in relation to plants
The second phase (with a brief interlude in the Lyceum of ancient Greece focused on plants themselves) entailed the systematization of plant knowledge, at first in relation to their medicinal properties (materia medica, herbals) but then in the refinement of their morphological structure and categorization into kinds. The advent and proliferation of printing through the 15th and 16th centuries, facilitated the sharing of information and standardization of terminology and it was at this time in history when botany diverged from medicine as medicinal botany followed one path into pharmacology and descriptive botany began its academic march towards plant science proper.

Botany then, by this understanding, consisted of the description and organization of the plant kingdom. It was the foundational inventory required before furtherr study could be pursued. Scientifically it entailed the standardization of methods and terms within a specialist plant group within the general scientific community. The emphasis of the study of botany was not on plant utility but the plants themselves: it was about plants in relation to plants as botany extricated itself from medicine to become a discrete academic discipline that persisted in this form until the early 19th century.

Phase 3 – Plant science

Plants in relation to nature
The third phase, ushered in by von Humbolt, placed emphasis on plants in relation to nature (the environment). This was botany coming of age in Industria as study moved from plant structure to plant process and change: it was a phase centred in Germany that eventually moved to Britain. While Humboldt, in the field, laid the foundations for a future ecology, his German colleagues experimented in laboratories to establish the principles of plant physiology and development. The study of plants had now evolved from static ‘botany’ to dynamic ‘plant science’ – from taxonomy, histology, and morphology, to physiology and ecology. This set the stage for the master of change, Charles Darwin, to reconfigure the entire field of biology.

Phase 4 – Plants & the future of humanity

Plants & the future
With the arrival of Informatia in the mid- 20th century, the study of plants has taken yet another turn. Plant science had solved, in principle, all the former mysteries of plant structure and function. No doubt this contributed to the advent of the Anthropocene, an era dominated by an exploding human population and its consumption. With the cracking of the genetic code, arrival of computers, information technology, globalization, and the environmental demands of human consumption, the former three phases have now been harnessed to address the future of humanity by investigating plants more deeply than ever before at the macro- and micro-scales. Environmental concern has harnessed global ecology to address climate change, species extinction, and environmental degradation of the biosphere, integrated with plant microbiology has been harnessed to address food security and the effective completion of an account of the community of life etc. What has transpired is that a large proportion of plant science is now addressing the complex global analysis and management of the place of plants in human ecology.

The path of plant knowledge

Knowledge builds on knowledge that already exists. And the more knowledge there is, the greater is the number of possible directions it can take. We can imagine the evolution of plant science by making the initial assumption that what counted as ‘true’ or scientific knowledge was knowledge that plant authorities from as wide a geographic base as possible, could agree about. Such an enterprise is facilitated in several ways. First, it requires a universal system of names, so that for each kind there is one name that is understood by everyone (nomenclature). Then, to simplify the way we access and manage all these names we need a way of grouping all the different kinds (classification). And if we are to make comparisons then we need descriptions (description). But to provide descriptions there needs to be a common language, that is, unambiguous terms referring to common characteristics, mostly those of structure or physical parts (e.g. the terminology needed for morphology). Together these universal features make up what today we know as taxonomy: nomenclature, classification, description, and terminology – at this stage relating only to gross morphology.

It took humanity up to the 19th century to, so-to-speak, get this far. Clearly one measure of a subject being called a ‘science’ is its use of categories of explanation that are universally acceptable within a scientific community.

This did not, however, occur sequentially with first the names, then the classification and so on. Rather there were various improving attempts at all of these together, although we do need names at a very early stage. We find the first plant lists in the papyri of ancient Egypt. Already rudimentary science was underway as the lists included synonymy, different names used for the same plant.

Plant utility

For most of human history, and for most people, human interest in plants related directly to self-interest. We want to know how we can use plants to our own advantage.

So far as we can tell, the first clearly recorded time when humans studied plants for their own sake was at the Lyceum of Theophrastus in ancient Athens.

Among the categories of plant science that have proliferated over time are the units (species) out of which the plant kingdom is comprised (units of nomenclature), the ways these units are grouped (classification or taxonomy), the structures of which these units are comprised (morphology, histology, anatomy, cytology, ultrastructure, biochemistry, and molecular biology) and the function that these structures serve (physiology, plant reproduction, plant evolution), the changes that plants have undergone from their time of origin on Earth (evolutionary biology, palaeontology), the changes that occur during growth and development in the course of a single generation (embryology, plant development), and the relationship between plants and their environments (ecology, plant geography).

From the mid twentieth century there have been an increasing number of plant studies relating to the impact of humans on plants (plant conservation, plant globalization, sustainability, weed science).

This article is about the history of plant science while the article on plant science people is a strictly chronological listing of influential plant scientists, the countries and cities where they lived and worked (using modern names) and a brief account of their work.

Following the emergence of plant science at the Lyceum of Theophrastus in ancient Athens the world of plant learning would be subsumed once again by medicine for about 2000 years. Botanical historian Alan Morton selects the year 1483, when Theophrastus’s works became available once more during the revival of learning we call the Renaissance. Perhaps the date could be set nearly a hundred years later when botany was distinguished from medicine by the appointment of professors of botany (Praefectoria simplicia) in the medical faculties of universities in Renaissance Italy of the early sixteenth century. These academic positions were associated with medicinal plant collections, and soon began specializing in plant nomenclature, classification and description to become modern era botanic gardens as the focus of plant research and learning. This was the century of Newton and the Scientific Revolution when philosophy fragmented into natural philosophy and natural science.

During the Scientific Revolution of the 16th and 17th centuries Copernicus had finally replaced the classical Ptolemaic view of the Earth as the centre of the solar system, Galileo had resisted religious dogma, and medicine had become more empirically based. Englishman Francis Bacon (1561-1626) in his Novum Organum (1620) attacked Aristotelian deductive logic and Aristotle’s preoccuption with final cause and teleology as the basis for scientific procedure, , observation, and experimentation. Supernatural perceptions of the physical world were being discarded as alchemy was transformed into modern chemistry, numerology into mathematics, and astrology was becoming more like modern astronomy. Old ideas from antiquity – of four humours (Galen), the four fundamental earthly elements of Earth, Air, Fire, and Water ( and four causes (Aristotle) were being replaced by a perception of the world as mechanistic cause and effect.

The development of botany, like the development of science in general, occurred within a social context. Listing the diversification of subject-matter along with the geographic location of its origin helps indicate the way commercial, cultural, and intellectual centres moved around Europe before moving overseas from the 15th century on. This Eurocentric perspective on these events is, in a broad sense, a consequence of the global distribution of political power but, more specifically, it indicates the sites where shared plant knowledge was being accumulated. There is no question that north American Indians and Australian Aboriginals possessed extensive local plant knowledge and experience, far more than the average European, and that the study of plants was also well advanced in the great Asian civilizations of India and China. But the written accumulation of plant knowledge on an intercontinental scale was an activity undertaken by Europeans with global interests. The historical development of plant science tracks the historical movement of centres of trade and learning first around Europe where economic and other resources were available to an academic or leisured intellectual class, and subsequently to colonial settlements and beyond.

 From the nineteenth century there has been a proliferation of disciplines relating to plant study. This is part of the refining process of plant study involving specializations of many kinds including many hybrid subjects like physiological ecology, molecular systematics, developmental morphology and so on, to the point where making an extended list has little value. The particular disciplines listed below are a selection of major ones among many.

Science occurs within a social context: it requires a community of like-minded individuals who can work together towards common goals. This is greatly facilitated by shared written symbolic languages, like mathematics.

In prehistory knowledge was passed on in an oral tradition except perhaps that possessed by shamans or religious leaders. However, with the Neolithic Revolution and the advent of writing and a social division of labour specialist plant knowledge became the possession of the few. Agriculture entailed a profound change in the relationship between humans and the natural world, entering a phase of co-evolution with the man-altered world of domesticated plants and animals. Day-to-day use of plants in agriculture or for structural material and ornament would have been the concern of uneducated labourers, artisans, and people associated with various crafts. Specialist plant knowledge, especially that associated with medicinal properties and herbal lore, was the domain of a social elite – the priests, physicians, and apothecaries – literate people who required special training and who were likely to keep written records. Though perhaps not so evident today, plant science is still the product of specialist training and knowledge gained in educational establishments.

Names & descriptions

Chapter 4 of Harvey and Totelin’s Ancient Botany addresses the problems of plant names in antiquity. There is always the question of the plant’s true identity.^[13] This is complicated by several factors: synonymy (many names for the same plant); multilingualism (though Greek served as a lingua franca names also appeared in local Latin, Egyptian, Cappadocian etc.); homonymy (the same name applying to dfferent plants); anonymity (the absence of a name); pseudonym (false names used to obscure the true identity); phytonymy (the use of Latin in prelinnaean names not always corresponding with current botanical usage). The Greek murtos corresponds to the myrtle or Myrtus in botanical Latin but the Greek kaktos refers to a thistle, not the cacti that we know.

Names might not include descriptions, crops might have changed under selection, and time takes its toll: the names of Theophrastus are different from those of Dioscorides.

In spite of all this scholiasts (commentators on ancient or classical literature) have tackled the identitiy of plants in Homer and all ancient literature and authorities like Galen have attempted to identify the plants indicated in the names used by their predecessors so the botanical lexicon flourished in antiquity and Middle Ages.

The first botanist to use Linnaean binomials for plants listed in ancient texts was Kurt Sprengel (1766-1833) who used the famous 10-vol. Flora Graeca by Englishman John Sibthorp to identify plants listed in Theophrastus’s two works. Then came Julius Billerbeck’s Flora Classica (1824) followed by many more.

Modern plant science & botanical gardens

Modern botany became a discipline in its own right, independent of medicine, when Italian universities appointed professors and teachers in botany, even though they were appointments within the medical faculty. The positions were called lector simplicium or professor simplicium. Francesco Bonafede was the first professor of botany, installed at Padua in 1533 by the Senate of the Republic of Venice which, at this time, dominated the lucrative spice trade.

Better known is Luca Ghini who became lector simplicium at Bologna in 1534 then professor simplicium in 1538 before being made, in 1544, director of the world’s first modern-era botanic garden in Pisa. Botanic gardens, set up virtually simultaneously, were associated with medical faculties and used for both teaching and study, the botany professors automatically becoming the garden directors. Ghini is attributed with the introduction of pressed and dried plant specimens (Hortus siccus – dried garden) thus preserving them in a form that would last for many years while also  being convenient for storage, study, and exchange. He built his own herbarium building to store the specimens, thus setting an example to many generations of future botanists. Ghini forged the link between descriptive botany, botanic gardens, and herbaria. Ghini was a leading figure contributing to the re-establishment of botany in the modern era.

A further initiative of these times was the botanically accurate depiction of plants as drawings and paintings made from living specimens.

By 1546 botanic gardens had been established at Pisa (founded by Cosimo I de Medici at Ghini’s request), Padua, and Florence to be followed within the next 20 years by new botanical gardens at Ferrara, Sassari, Bologna and elsewhere in Italy. The institution of the botanic garden then took 35 to 100 years to spread from Italy to northern and western Europe as traced through the establishment dates of major city botanic gardens: Pisa 1544, Padua and Fllorence 1545, Balogna 1568, Valencia 1567, Montpellier 1593, Leiden 1587, Leipzig 1597, Oxford 1621, Paris 1635, Berlin 1646, Uppsla 1655, Edinburgh 1670, Chelsea Physic Garden 1673 and Amsterdam 1682.

Botanic gardens would, for many years to come, be the major institutions for original botanical thinking.

Early influences of Theophrastus’s work

1470-1670 Printing & Herbals

Printing began in the fifteenth century and had a dramatic impact on scientific communication. Among the first printed books were compendia of herb descriptions called Herbals, mostly repeating the content of De Materia Medica and Naturalis Historia. Herbals are best known as books published after the invention of moveable type by Johannes Gutenberg in the early fifteenth century and associated with Western Europe in the period between 1470 and 1670 and especially the Low Countries, Germany and England. In these publications descriptions of medicinal properties, or ‘virtues’ as they were often known, were frequently enhanced by beautiful woodcut or metal-engraved plant illustrations that were hand-painted after printing and the plants described were often represented by specimens stoted in herbaria. Major herbals dating from this period include those of: Germans – Bock (1539), Brunfels (1530) and Fuchs (1542); Englishmen – Gerard (1597), Turner (1551-1568), Parkinson (1629), and Culpepper (1649); and from the Low Countries – Lobel (1570), and Clusius (1601).

Floras and pharmacopoias

Gradually herbals paid more attention to botanical features and where plants grew, containing more methodical descriptions of plant parts, classification, and illustrations that would facilitate identification. The herbal was transformed, on the one hand, into a botanical flora – a botanical account of the plants growing in a particular region – while, on the other hand, medicinal properties became part of pharmacology and its encyclopaedic pharmacopoeias. Both the new directions reduced much of the former folklore and magic, along with many of the dubiously effective potions, poultices, concoctions, decoctions, ointments and the like. Pharmacopoeias prepared the way for modern synthetic and industrially-produced drugs.

Empiricism, gardens, globalization- 1623 to 1694

Empiricism

Plant science historian Alan Morton (1981) notes a qualitative change in scientific activity during the first decades of the 17th century.

In 1620 Englishman Francis Bacon published in Latin his Novum Organum. Bacon’s natural philosophy began with the senses and his emphasis on experiment and observation. This, when combined with the logic of eliminative induction, laid a firm foundation for empiricism . . . it heralded the birth of modern science and what came to be known as the ‘Scientific Method’. Bacon’s new approach came at a time when microscopes and telescopes were beginning to extend our sensory capacities into scales of existence that were not apparent to our unaided senses: the world of cells, mites, and the mountains on the moon.

The title page of Novum Organum (a reference to Aristotle’s treatise on logic, the Organon) depicts a galleon sailing through the mythical Pillars of Hercules on each side of the Strait of Gibraltar symbolising an exit from the well-charted waters of the Mediterranean into the Atlantic Ocean. The Pillars, as the boundary of the Mediterranean, have been breached revealing a ‘New World’ of exploration. Bacon is implying that empirical investigation will, in a similar way, leave behind the old ideas of the ancient world on its way to a better scientific understanding of the Earth, life, and the heavens.

Joachim Jung (1587-1657) was a professor of mathematics at Giessen in Germany who then studied medicine in Rostock and Padua before returning to Germany, where he held several academic posts acquiring a reputation as a fine teacher. Two of his students published, after his death Isagoge Phytoscopica (1678) which was essentially a theoretical system of botany written in the form of a logical sequence of Aristotelian propositions, like Part 1 of Theophrastus’s Historia Plantarum and other books of early theoretical botany. His carefully observed and defined botanical glossary included many terms for leaves and flowers used for the first time and without reference to function. This work and an earlier simpler work De Plantis Doxoscopiae Physicae Minores (1662) were published in combination in 1747. Jung’s place in the history of botany was sealed when a led when a manuscript of Isagoge . . . was obtained by Ray in 1660 who used most of it in the introduction to his Historia Plantarum (1686) on the way to Linnaeus‘s later keen eye.

Gardens for all

The popular narrative of gardens and gardening follows those with the means to create substantial horticultural displays – which, in antiquity and the first centuries of the modern era, meant royalty and the aristocracy.

It is in this period that ornamental horticulture and especially the flower garden, begins to take hold within a wider section of society. One strong signal of this was a publication by Englishman John Parkinson (1567-1650), apothecary to James I who was given the title Botanicus Regius Primarius by James’s successor Charles I. The title of the publication was a play on words Paradisi in Sole Paradisus Terrestris (Park-in-Sun’s Earthly Paradise). Here he describes over 1000 plants, many being new introductions and these are illustrated with 780 woodcuts (not original). Garden author Penelope Hobhouse remarks that this was probably ‘the first English work to consider flowers for their beauty rather than their use as herbs.^[16] This was followed by his Theatrum Botanicum (1640) which considered 3800 different plants, probably incorporating Lobel’s work as he had purchased Lobel’s manuscripts (presumably when he died). But the work of John Goodyer and John Tradescant the Elder was also acknowledged along with Flemish William Boel who had collected seeds for him in Germany, Spain, Portugal and north Africa (known at that time as the Barbary coast).

Age of Discovery

In the late 15th century an Age of Discovery was unleashed as Spain and Portugal launched a maritime spice race to the East Indies that followed both eastern and western sea lanes around the world. The encounter with the Americas by Columbus in 1492 opened up to western Europe the resources of a New World across the Atlantic. Soon silver and gold were being shipped by the Spanish into Europe from the Americas, and Portugal ended the millennia-old hunt for the mysterious source of the lucrative nutmeg and cloves by locating them on the small Banda Islands  in the Malaccas.

Colonial expansion

As political fortunes waxed and waned global exploration was led first by the Portuguese and Spanish in the 16th century followed by the Dutch in the 17th century and, in the 18th century Enlightenment, by the French and British.

Spain and Portugal began their exploration of the world outside the Mediterranean by  first settling the Atlantic islands off the coast of northwest Africa (Canaries, Azores, Cape Verde) and then venturing westwards to the Americas (1419-1507) before reaching the Indian (1497-1513) and Pacific (1513-1529) Oceans.

Scientific accounts of the biota of these new regions was quick to follow. A natural history of Latin America was published by the Jesuit José de Costa (1539-1600) in 1570 based on his work in Peru. Francisco Hernández lived for seven years in Mexico working on medicinal plants his Plants and Animals of New Spain describing over 3000 new plants while Nicolas Monárdes (1493-1588) published on the plants of the West Indies. Portuguese Garcia de Orta (1501-1568) and Cristóvao da Costa (1515-1594) published on the medicinal plants of India and Southeast Asia.

Circumnavigation of the world by Portuguese explorer Magellan’s expedition of 1519-1522 proved conclusively that the world was a sphere (he did not survive the voyage) and in so doing a seemingly infinite and all-bountiful world acquired physical and biological boundaries. Sea voyages of exploration in the Age of Discovery changed into Enlightenment expeditions of scientific exploration returning a flood of botanical treasures to the large public, private, and newly established botanic gardens. An eager population revelled in the novel crops, drugs and spices from Asia, the East Indies and the New World. These curious, beautiful and new plants required names, descriptions, classification, illustration and cataloging, stimulating a major phase of descriptive plant taxonomy. Botanic gardens associated with universities became the new centres of plant science as botany became a subject in its own right soon fragmenting into sub-disciplines of its own.

1694-1753 – THE WORLD FLORA & ITS DESCRIPTION

With improvements in navigation, coastal charting and shipbuilding the world was opening up to European botanists.

One obvious source of new plants was the British colonies in Virginia.

1750-1850 Botanophilia

All this was combined with a new public engagement that resulted in a frenzy of botanical interest (see extended discussion in the article botanophilia) that resulted in the amassing of plant collections as part of a surge in economic botany, ornamental horticulture, sophisticated landscape design, and scientific research, all at a time when new technology was revolutionising agriculture, horticulture and forestry. Europe had entered a romantic era of botanical explorers, intrepid plant hunters and gardener-botanists. Significant botanical collections came from: the West Indies (Hans Sloane (1660–1753)); China (James Cunningham); the spice islands of the East Indies (Moluccas, George Rumphius (1627–1702)); China and Mozambique (João de Loureiro (1717–1791)); West Africa (Michel Adanson (1727–1806)) who devised his own classification scheme and forwarded a crude theory of the mutability of species; Canada, Hebrides, Iceland, New Zealand by Captain James Cook‘s chief botanist Joseph Banks (1743–1820)(see Plant introduction)^[50] Plant nurseries and commercial horticulture thrived as never before.

Rise of science

Science too was becoming a respectable enterprise, not just a rich man’s diversion or a minor source of useful practical knowledge in a world of religious meaning and explanation. The return to analytical empiricism was to culminate in the celebration of logic and science during the European Enlightenment of the eighteenth century. The number of scientific publications soon multiplied. In England, for example, scientific communication and scientific causes were facilitated by learned societies like Royal Society (founded in 1660) and the Linnaean Society (founded in 1788). There was also the support and activities of botanical institutions like the Jardin du Roi in Paris, the Oxford-, Cambridge- and Chelsea Physic Gardens as well as the influence of renowned private gardens and wealthy entrepreneurial nurserymen. Medicinal herbals changed into Floras as books listing, describing and sometimes also illustrating the plants growing in particular regions. By the early 17th century the number of plants described in Europe had risen to about 6000.

Colonial exploration during the Age of Discovery prompted a flurry of botanical activity as plant trophies from distant lands were returned to decorate the gardens of Europe’s powerful and wealthy in a period of enthusiasm for natural history and botany known as ‘botanophilia‘ an obsession that will never recur. Flower painting reached its height at this time while for botanists this was a true return to science through the encyclopaedic task of plant description, classification, nomenclature, identification, and illustration. Most outstanding of all the naturalists of this period was Carl Linnaeus, the ‘father of plant classification’, but there were many others.

We can see a transition from the first listings and accounts of plants within empire Theophrastus th Greek, Pliny the Roman, the colonial floras of the British Empire, latter-day work in the tropics and the advent of modern on-line plant databases and first installments of a World Flora initiated in 2012 through the Missouri Botanical Garden, Royal Botanic Gardens, Kew, Royal Botanic Garden Edinburgh and New York Botanical Garden.

Women in science

It is a sad aspect of human history that, until recent times, women have been given a secondary role in society, for the most part confined to the home – albeit the management of large estates in the case of the landed gentry and aristocracy. Part of the problem was the desire to preserve and control dynastic continuity by keeping women securely constrained; part was the tradition of primogeniture designed to keep property intact (not broken up by dividing it among many children) within the male line; and of course various prejudices concerning ‘natural’ biological and social differences between the male and female.

Botany has been no exception to this general rule although, as in other areas of life, there have been a few exceptional women who have overcome male barriers. Among those deserving special attention as leaving a permanent impression on the subject are Abbess Hildegard of Bingen.

In the 17th century Mary Somerset, the Duchess of Beaufort (1630-1715) was a botanically well-read friend of John Ray and Hans Sloane. She accumulated and recorded both living and dried plants from her collections in London and Badminton (accumulated from South Africa, West Indies, Sri Lanka, Virginia, India, Japan and China), the latter with fine stove houses rivalling those of Queen Mary at Hampton Court and containing the latest exotic fruits. A society lady, at Badminton she employed the botanist William Sherard to tutor her grandson, taking advantage of his knowledge and contacts to accumulate some 1500 more plants for her collection. She also held a fine orchard and orangerie. In London, at Beaufort House there were some more of her favourite plants including a collection of those with variegated, mostly striped, foliage plants in pots. Many of her plants were acquired from George London of the Brompton Park Nursery and gardener to William III at Hampton Court and she kept a record of the merchant ships and captains who had brought the plants to England. No doubt a proportion of her plants were new and undescribed species. She ensured a record of some of her favourites by initiating a two-volume Florilegium of botanical illustrations, the first volume painted by Evergardus Kickius and the second by Daniel Francome and now in the library at Badminton. She bequeathed a 12-volume herbarium of pressed plants to the Natural History Museum. In 1812 Robert Brown commemorated her contribution to botany by naming an Australian genus, Beaufortia.

18th century botany was one of the few sciences considered appropriate for genteel educated women. Around 1760, with the popularization of the Linnaean system, botany became much more widespread among educated women who painted plants, attended classes on plant classification, and collected herbarium specimens although emphasis was still on the healing and aesthetic properties of plants rather than plant reproduction which had overtones of sexuality which were considered too confronting for the fairer sex. Women began publishing on botanical topics and children’s books on botany appeared by authors like Charlotte Turner Smith. Cultural authorities argued that education through botany created culturally and scientifically aware citizens, part of the thrust for ‘improvement’ that characterised the Enlightenment. However, in the early 19th century with the recognition of botany as an official science women were again excluded from the discipline.

Plant structure

Descriptive botany had become reinvigorated with the printing of Herbals which became more comprehensive and botanically rigorous to eventually take the form of the modern Flora. Credit for this achievement is given to Swedish naturalist Carl Linnaeus (1707-1778).

Influential predecessors included Swiss scholar Conrad Gessner (1516-1565) who discovered many new plants while climbing the Swiss Alps. He proposed that there were groups or genera of plants, each genus composed of many species and that these were defined by similar flowers and fruits. This principle of organization laid the groundwork for future botanists and he wrote the important Historia Plantarum shortly before his death. Carolus Clusius (1526-1609), possibly the most influential of botanical horticulurists of the sixteenth century, trained at Montpelier, he established the Leiden Botanic Garden where he was appointed university professor and noting the virus-induced colouring of tulips that triggered tulipomania. Clusius had journeyed throughout most of Western Europe, making discoveries in the vegetable kingdom along the way. He was the first to propose dividing plants into classes.

Italian physician Andrea Caesalpino (1519–1603) was a teacher at the University of Pisa before becoming Director of the Botanic Garden of Pisa from 1554 to 1558 and author of the 16-volume De Plantis (1583) (published the same year as Dodoens’s Pemptades) described 1500 plants and was, in effect, the first scientific treatise on plants since the works of Theophrastus, the first volume being a 30-page exposition of theoretical botany up to his day: his herbarium of 260 pages and 768 mounted specimens still survives and can be viewed in the Oxford University library. Though aware of the ‘natural’ systems of Pena and Lobel, it was Caesalpino that earned from Linnaeus recognition as being the first true systematist. Caesalpino organised plants into genera and classes based largely on the structure of flowers and fruit. It was on Caesalpino’s ideas that Tournefort and Linnaeus would subsequently build a more securely universal system of plant inventory.

By the 1620’s the number of scientifically known plants totalled about 6000 species as listed in Gaspard Bauhin’s (1560–1624) Prodromus Theatrici Botanici (1620) and Pinax (1623), the latter publication using two-word names or binomials (most botanists at this time were using short descriptive phrases) while also listing the several names that had been used for the same plant (synonyms) and where they were published, thereby linking the descriptive botanical literature, a valuable insight later used by Linnaeus.

Precise descriptions were needed for accurate identification demand an unambiguous terminology for the many plant structures. A rigorous botanical terminology was devised by German philosopher Joachim Jung (1587–1657) and augmented by English botanist John Ray (1623–1705). Volumes 1 and 2 of Ray’s three-volume Historia Plantarum (1686, 1688, 1704) describes and classifies about 7000 species of British and European plants and, in effect, the first botanical synthesis and text book for modern botany, while the third volume adds a further 11,700 entries including plants from Jamaica, the Philippines, Africa and the Far East as a substantial step towards the ultimate goal of a world flora.^[3] He encouraged the use of all plant parts in his classification system and noted the distinction between variation deriving from external environmental and internal factors, and being the first to give a biological definition of the term species. Many of his groupings anticipated modern plant families. He was also among the first experimental physiologists and according to botanical historian Alan Morton ‘influenced both the theory and the practice of botany more decisively than any other single person in the latter half of the seventeenth century‘.^[4]

Naming, description, classification, illustration & cataloguing

Up to the 17th century botany and medicine were one and the same but with the advent of the Flora backed by specimens deposited in a herbarium and plant studies that largely ignored medicinal uses the botanical break from medicine was complete. Plant classification systems of the 17th and 18th centuries now related plants to one another and not to man, marking a return to the non-anthropocentric botanical science promoted by Theophrastus over 1500 years before. By the middle of the 18th century the botanical booty resulting from the era of exploration was accumulating in gardens and herbaria – and it needed to be systematically catalogued. This was the task of the taxonomists, the plant classifiers.

Classification 1650-1750 ->

With a diversity of botanical terminology, the same plants being described under different names in different countries there was a desperate need for a standardised system of naming, describing and classifying organisms to facilitate the difficult business of scientific communication. Ray’s family system was later extended by Pierre Magnol (1638–1715) and Joseph de Tournefort (1656–1708), a student of Magnol, achieved notoriety for his botanical expeditions, his emphasis on floral characters in classification, and for reviving the idea of the genus as the basic unit of classification.

Linnaeus’s great contribution was to synthesise former work into a practical and universal system for cataloguing plants, one that was acceptable to all – a remarkable feat whose legacy remains at the heart of biological classification and nomenclature today. Linnaeus devised a ‘sexual system’ of classification with the numbers and arrangement of stamens and pistils as crucial characters. Gradually he published the necessary background matter needed to support his later ideas: Systema Naturae (1735), Genera Plantarum (1737), and Philosophia Botanica (1751). For botanists it is Species Plantarum (1753) for which he is best known as in this book he gave every species a binomial, a two-word name like our own forename and surname, thus establishing the path for the future accepted method of designating the names of all organisms.

The groundwork laid by Linnaeus has remained, to be refined by more detailed study and supplemented by the new information revealed by modern technology. Classifications have changed from ‘artificial’ systems based on convenient characters of general habit and form, to pre-evolutionary ‘natural’ systems expressing more precisely the similarity and differences between organisms using one to many characters. Linnaeus used a practical artificial system recognising that a more scientific natural system would inevitably follow. Today’s ‘natural’ systems are used to infer evolutionary relationships.

Natural classification – 1700-1800

As anticipated his sexual system was later elaborated into the natural system of French naturalist Bernard de Jussieu (1699–1777), botanist at Le Jardin des Plantes in France. In 1759 Bernard laid out beds of plants in the royal garden (Jardin du Roi, later the Jardin du Plantes) of Trianon in the Palace of Versailles (see Josephine de Beauharnais) according to his own particular scheme or system of classification – to produce what we now know as a ‘system garden’. Frenchman botanists were active at this time, this particular system being modified again by his nephew Antoine-Laurent de Jussieu (1748–1836) and further refined by Michel Adanson (1727–1806) in his Familles des Plantes (1763, 1764) whose classification used many characters, the most diagnostic ones depending on the particular plant group, while also adding more plant families – a system that is followed broadly today. It was but the major principles of taxonomy on which modern classification is based were established in the period 1650-1750.

Classification 1800-1900

From Enlightenment taxonomy we were bequeathed a precise binomial nomenclature and botanical terminology, a system of classification that is based on natural affinities, and a clear idea of the ranks of family, genus and species — although the taxa to be placed within these ranks remains, as always, the subject of taxonomic research. Linnaeus also set a precedent for formal plant description and the listing of plants that included synonyms and former literature. From Linnaeus on, the botanical task of creating a world flora was a clear goal. Today we are well down this path with work now concentrated in the tropics.

From the nineteenth century ‘New and revised “phylogenetic” classification systems of the plant kingdom were produced, perhaps the most notable being that of August Eichler (1839–1887), and the massive 23 volume Die natürlichen Pflanzenfamilien of Adolf Engler (1844–1930) & Karl Prantl (1849–1893) published over the period 1887 and 1915.

Classification 1900-present

Plant taxonomy (perhaps better known today as phylogenetic systematics) has continued its work by adding many more characters as revealed using modern technology – from electron microscopy, palynology, biochemistry, genetics (as genomics, molecular systematics, etc.) and speeding up analysis through the use of computers as informatics (phenetics, taximetrics, cladistics, bioinformatics etc.). Taxonomy based on gross morphology was now being supplemented by using characters revealed by pollen morphology, embryology, anatomy, cytology, serology, macromolecules and more.[98] The introduction of computers facilitated the rapid analysis of large data sets used for numerical taxonomy (also called taximetrics or phenetics). The emphasis on truly natural phylogenies spawned the disciplines of cladistics and phylogenetic systematics. The grand taxonomic synthesis An Integrated System of Classification of Flowering Plants (1981) of American Arthur Cronquist (1919–1992) was superseded when, in 1998, the Angiosperm Phylogeny Group published a phylogeny of flowering plants based on the analysis of DNA sequences using the techniques of the new molecular systematics which was resolving questions concerning the earliest evolutionary branches of the angiosperms (flowering plants). The exact relationship of fungi to plants had for some time been uncertain. Several lines of evidence pointed to fungi being different from plants, animals and bacteria – indeed, more closely related to animals than plants. In the 1980s-90s molecular analysis revealed an evolutionary divergence of fungi from other organisms about 1 billion years ago – sufficient reason to erect a unique kingdom separate from plants.

The microscope & plant anatomy 1650-1700

This approach coupled with the new Linnaean system of binomial nomenclature resulted in plant encyclopaedias without medicinal information called Floras that meticulously described and illustrated the plants growing in particular regions. The 17th century also marked the beginning of experimental botany and the application of a more rigorous scientific method, while improvements in the microscope launched the new discipline of plant histology and anatomy whose foundations, laid by the careful observations of Englishmen Robert Hooke, Nehemiah Grew and Italian Marcello Malpighi, would last for 150 years.

The invention of the microscope and improved lens grinding allowed plants to be observed, described and analysed at a totally different scale leading to the foundation of plant anatomy by Italian Marcello Malpighi and Englishman Nehemiah Grew between 1650 and 1700. Their work marked the beginnings of developmental anatomy and morphology, observing, describing, naming and drawing the changes in structure of tissues and cells at all stages of plant growth from seed to mature plant including wood formation.

During the 19th century German scientists led the way towards a unitary theory of the structure and life-cycle of plants. Following improvements in the microscope at the end of the 18th century, Charles Mirbel (1776–1854) in 1802 published his Traité d’Anatomie et de Physiologie Végétale and Johann Moldenhawer (1766–1827) published Beyträge zur Anatomie der Pflanzen (1812) in which he describes techniques for separating cells from the middle lamella. He identified vascular and parenchymatous tissues, described vascular bundles, observed the cells in the cambium, and interpreted tree rings. He found that stomata were composed of pairs of cells, rather than a single cell with a hole.

Anatomical studies on the stele were consolidated by Carl Sanio (1832–1891) who described the secondary tissues and meristem including cambium and its action. Hugo von Mohl (1805–1872) summarized work in anatomy leading up to 1850 in Die Vegetabilische Zelle (1851) but this work was later eclipsed by the encyclopaedic comparative anatomy of Heinrich Anton de Bary in 1877. An overview of knowledge of the stele in root and stem was completed by Van Tieghem (1839–1914) and of the meristem by Karl Nägeli (1817–1891). Studies had also begun on the origins of the carpel and flower that continue to the present day.

Cytology

The cell nucleus was discovered by Robert Brown in 1831. Demonstration of the cellular composition of all organisms, with each cell possessing all the characteristics of life, is attributed to the combined efforts of botanist Matthias Schleiden and zoologist Theodor Schwann (1810–1882) in the early 19th century although Moldenhawer had already shown that plants were wholly cellular with each cell having its own wall and Julius von Sachs had shown the continuity protoplasm between cell walls.

From 1870 to 1880 it became clear that cell nuclei are never formed anew but always derived from the substance of another nucleus. In 1882 Flemming observed the longitudinal splitting of chromosomes in the dividing nucleus and concluded that each daughter nucleus received half of each of the chromosomes of the mother nucleus: then by the early 20th century it was found that the number of chromosomes in a given species is constant. With genetic continuity confirmed and the finding by Eduard Strasburger that the nuclei of reproductive cells (in pollen and embryo) have a reducing division (halving of chromosomes, now known as meiosis) the field of heredity was opened up. By 1926 Thomas Morgan was able to outline a theory of the gene and its structure and function. The form and function of plastids received similar attention, the association with starch being noted at an early date. With observation of the cellular structure of all organisms and the process of cell division and continuity of genetic material, the analysis of the structure of protoplasm and the cell wall as well as that of plastids and vacuoles – what is now known as cytology, or cell theory became firmly established.

Later, the cytological basis of the gene-chromosome theory of heredity extended from about 1900–1944 and was initiated by the rediscovery of Gregor Mendel’s (1822–1884) laws of plant heredity first published in 1866 in Experiments on Plant Hybridization and based on cultivated pea, Pisum sativum: this heralded the opening up of plant genetics. The cytological basis for gene-chromosome theory was explored through the role of polyploidy and hybridization in speciation and it was becoming better understood that interbreeding populations were the unit of adaptive change in biology.

Plant function

Experimental science & plant physiology

Botany from the time of Theophrastus could be divided straightforwardly into pure and applied domains. Early natural history had created three major botanical streams morphology (classification), anatomy and physiology – that is, external form, internal structure, and functional operation, while the three most obvious streams in applied botany were horticulture, forestry and agriculture – although from now on disciplines began to emerge that did not fall into such neat categories as technology has opened up new techniques and widened the scope of study: weed science, ethnobotany, plant pathology, pharmacognosy, and economic botany and which sit uneasily, if at all, in modern plant science. Specialists now began to confine their interest to the botany of particular plant groups phycology (algae), pteridology (ferns), mycology (fungi, before these were placed in aseparate kingdom), bryology (mosses and liverworts) and palaeobotany (fossil plants).

Classifying plants was for the most part the routine process of descriptive science but the first half of the 18th century marked a move into experimental science – an examination of the way plants functioned and interacted with their environment over many scales from the large-scale global distribution and biological significance of vegetation and plant communities (biogeography and ecology) to the small scale processes operating within the plant as revealed by new subjects like cell theory, experimental physiology, molecular biology and plant biochemistry.

In plant physiology research interest was focused on the movement of sap and the absorption of substances through the roots. Jan Helmont (1577–1644) by experimental observation and calculation, noted that the increase in weight of a growing plant cannot be derived purely from the soil, and concluded it must relate to water uptake. Englishman Stephen Hales (1677–1761) established by quantitative experiment that there is uptake of water by plants and a loss of water by transpiration and that this is influenced by environmental conditions: he distinguished ‘root pressure’, ‘leaf suction’ and ‘imbibition’ and also noted that the major direction of sap flow in woody tissue is upward. His results were published in Vegetable Staticks (1727) He also noted that ‘air makes a very considerable part of the substance of vegetables’. English chemist Joseph Priestley (1733–1804) is noted for his discovery of oxygen (as now called) and its production by plants. Later Jan Ingenhousz (1730–1799) observed that only in sunlight do the green parts of plants absorb air and release oxygen, this being more rapid in bright sunlight while, at night, the air (CO₂) is released from all parts. His results were published in Experiments upon vegetables (1779) and with this the foundations for 20th century studies of carbon fixation were laid. From his observations he sketched the cycle of carbon in nature even though the composition of carbon dioxide was yet to be resolved. Studies in plant nutrition had also progressed. In 1804 Nicolas-Théodore de Saussure’s (1767–1845) Recherches Chimiques sur la Végétation was an exemplary study of scientific exactitude that demonstrated the similarity of respiration in both plants and animals, that the fixation of carbon dioxide includes water, and that just minute amounts of salts and nutrients (which he analysed in chemical detail from plant ash) have a powerful influence on plant growth.

Water relations

The nineteenth century saw major advances in plant physiology, mostly through the research of German botanists determined to elucidate water and nutrient transport through the plant. Much of the work of this period especially was carried out in the laboratories of Julius Sachs (1832-1897) and synthesised in his book Vorlesungen über Pflanzenphysiologie (1882).

Carbon fixation (photosynthesis)

At the start of the 19th century the idea that plants could synthesise almost all their tissues from atmospheric gases had not yet emerged. The energy component of photosynthesis, the capture and storage of the Sun’s radiant energy in carbon bonds (a process on which all life depends) was first elucidated in 1847 by Mayer, but the details of how this was done would take many more years.[88] Chlorophyll was named in 1818 and its chemistry gradually determined, to be finally resolved in the early 20th century. The mechanism of photosynthesis remained a mystery until the mid-19th century when Sachs, in 1862, noted that starch was formed in green cells only in the presence of light and in 1882 he confirmed carbohydrates as the starting point for all other organic compounds in plants.[89] The connection between the pigment chlorophyll and starch production was finally made in 1864 but tracing the precise biochemical pathway of starch formation did not begin until about 1915.

Nitrogen fixation

Significant discoveries relating to nitrogen assimilation and metabolism, including ammonification, nitrification and nitrogen fixation (the uptake of atmospheric nitrogen by symbiotic soil microorganisms) had to wait for advances in chemistry and bacteriology in the late 19th century and this was followed in the early 20th century by the elucidation of protein and amino-acid synthesis and their role in plant metabolism. With this knowledge it was then possible to outline the global nitrogen cycle.

Other discoveries and studies included osmosis and geotropism.

Economic botany

Advances in economic botany have benefitted from basic botanical research into plant physiology, genetics and so on, but empiricism is not confined to universities. Practical applied knowledge could be improved and made more efficient by constant critical observation noting what worked and what did not. Plants have always been the source of energy for our bodies so food has never been of secondary importance.

Perhaps unknowingly today’s familiar staple foods were all domesticated in prehistory. Seed would be collected from the high-yielding plants leading to the selection of higher-yielding varieties. Plants like peas and beans (legumes) were cultivated on all continents but cereals made up most of the basic diet on all continents except possibly Australia. There was rice in East Asia, maize in southern and central America, wheat and barley in the Middle east supplemented by local foods. In Greco-Roman times cereals were supplemented in the Mediterranean by grapes, apples, figs, and olives, Roman manuscripts already alluding to particular cultivated varieties of these plants. Botanical historian William Stearn has observed that ‘cultivated plants are mankind’s most vital and precious heritage from remote antiquity‘.

Though many Greek manuscripts were written on the subject of farming it was the practical Romans who left the founding texts from which later industrial agriculture would emerge.

Plant reproduction 1700-1800

Tracing the finer detail of plant sexuality requires not only good analytic kills but careful microscopic observation and only in 1694 was it conclusively shown that ovule development needed fertilization by pollen from the stamens finally confirming observations made years before by Babylonians observing date palms in Assyria in at least 885-860 BCE^[8], Empedocles (490-430 BCE) and Theophrastus (371-287 BCE). From these early observations work across plant groups revealed the ‘alternation of generations’ and opened up the field of comparative morphology leading in the early19th century to an understanding of nectar and the role of insects and wind in pollination.

Nineteenth century foundations of modern botany

In about the mid-19th century scientific communication changed. Until this time ideas were largely exchanged by reading the works of authoritative individuals who dominated in their field: these were often wealthy and influential “gentlemen scientists”. Now research was reported by the publication of “papers” that emanated from research “schools” that promoted the questioning of conventional wisdom. This process had started in the late 18th century when specialist journals began to appear. Even so, botany was greatly stimulated by the appearance of the first “modern” text book, Matthias Schleiden’s (1804–1881) Grundzüge der Wissenschaftlichen Botanik, published in English in 1849 as Principles of Scientific Botany. By 1850 an invigorated organic chemistry had revealed the structure of many plant constituents.[74] Although the great era of plant classification had now passed the work of description continued. Augustin de Candolle (1778–1841) succeeded Antoine-Laurent de Jussieu in managing the botanical project Prodromus Systematis Naturalis Regni Vegetabilis (1824–1841) which involved 35 authors: it contained all the dicotyledons known in his day, some 58000 species in 161 families, and he doubled the number of recognized plant families, the work being completed by his son Alphonse (1806–1893) in the years from 1841 to 1873.

Plant geography and ecology 1800-present

The opening of the 19th century was marked by an increase in interest in the connection between climate and plant distribution. Carl Willdenow (1765–1812) examined the connection between seed dispersal and distribution, the nature of plant associations and the impact of geological history. He noticed the similarities between the floras of N America and N Asia, the Cape and Australia, and he explored the ideas of ‘centre of diversity’ and ‘centre of origin’. German Alexander von Humboldt (1769–1859) and Frenchman Aime Bonpland (1773–1858) published a massive and highly influential 30 volume work on their travels; Robert Brown (1773–1852) noted the similarities between the floras of S Africa, Australia and India, while Joakim Schouw (1789–1852) explored more deeply than anyone else the influence on plant distribution of temperature, soil factors, especially soil water, and light, work that was continued by Alphonse de Candolle (1806–1893). Joseph Hooker (1817–1911) pushed the boundaries of floristic studies with his work on Antarctica, India and the Middle East with special attention to endemism. August Grisebach (1814–1879) in Die Vegetation der Erde (1872) examined physiognomy in relation to climate and in America geographic studies were pioneered by Asa Gray (1810–1888).

Physiological plant geography, perhaps more familiarly termed ecology, emerged from floristic biogeography in the late 19th century as environmental influences on plants received greater recognition. Early work in this area was synthesised by Danish professor Eugenius Warming (1841–1924) in his book Plantesamfund (Ecology of Plants, generally taken to mark the beginning of modern ecology) including new ideas on plant communities, their adaptations and environmental influences. This was followed by another grand synthesis, the Pflanzengeographie auf Physiologischer Grundlage of Andreas Schimper (1856–1901) in 1898 (published in English in 1903 as Plant-geography upon a physiological basis translated by W. R. Fischer, Oxford: Clarendon press, 839 pp.)

Developmental morphology and evolution

Until the 1860s it was believed that species had remained unchanged through time: each biological form was the result of an independent act of creation and therefore absolutely distinct and immutable. But the hard reality of geological formations and strange fossils needed scientific explanation. Charles Darwin’s On the Origin of Species (1859) replaced the assumption of constancy with the theory of descent with modification. Phylogeny became a new principle as ‘natural’ classifications became classifications reflecting, not just similarities, but evolutionary relationships. Wilhelm Hofmeister established that there was a similar pattern of organization in all plants expressed through the alternation of generations and extensive homology of structures.

Polymath German intellect Johann Goethe (1749–1832) had interests and influence that extended into botany. In Die Metamorphose der Pflanzen (1790) he provided a theory of plant morphology (he coined the word “morphology”) and he included within his concept of ‘metamorphosis’ modification during evolution, thus linking comparative morphology with phylogeny. Though the botanical basis of his work has been challenged there is no doubt that he prompted discussion and research on the origin and function of floral parts.[86] His theory probably stimulated the opposing views of German botanists Alexander Braun (1805–1877) and Matthias Schleiden who applied the experimental method to the principles of growth and form that were later extended by Augustin de Candolle (1778–1841).

Twentieth century

20th century science grew out of the solid foundations laid by the breadth of vision and detailed experimental observations of the 19th century. A vastly increased research force was now rapidly extending the horizons of botanical knowledge at all levels of plant organization from molecules to global plant ecology. There was now an awareness of the unity of biological structure and function at the cellular and biochemical levels of organisation. Botanical advance was closely associated with advances in physics and chemistry with the greatest advances in the 20th century mainly relating to the penetration of molecular organization.[91] However, at the level of plant communities it would take until mid century to consolidate work on ecology and population genetics.[92] By 1910 experiments using labelled isotopes were being used to elucidate plant biochemical pathways, to open the line of research leading to gene technology. On a more practical level research funding was now becoming available from agriculture and industry.

Molecules

In 1903 Chlorophylls a and b were separated by thin layer chromatography then, through the 1920s and 1930s, biochemists, notably Hans Krebs (1900–1981) and Carl (1896–1984) and Gerty Cori (1896–1957) began tracing out the central metabolic pathways of life. Between the 1930s and 1950s it was determined that ATP, located in mitochondria, was the source of cellular chemical energy and the constituent reactions of photosynthesis were progressively revealed. Then, in 1944 DNA was extracted for the first time.[93] Along with these revelations there was the discovery of plant hormones or “growth substances”, notably auxins, (1934) gibberellins (1934) and cytokinins (1964)[94] and the effects of photoperiodism, the control of plant processes, especially flowering, by the relative lengths of day and night.

Following the establishment of Mendel’s laws, the gene-chromosome theory of heredity was confirmed by the work of August Weismann who identified chromosomes as the hereditary material. Also, in observing the halving of the chromosome number in germ cells he anticipated work to follow on the details of meiosis, the complex process of redistribution of hereditary material that occurs in the germ cells. In the 1920s and 1930s population genetics combined the theory of evolution with Mendelian genetics to produce the modern synthesis. By the mid-1960s the molecular basis of metabolism and reproduction was firmly established through the new discipline of molecular biology. Genetic engineering, the insertion of genes into a host cell for cloning, began in the 1970s with the invention of recombinant DNA techniques and its commercial applications applied to agricultural crops followed in the 1990s. There was now the potential to identify organisms by molecular ‘fingerprinting’ and to estimate the times in the past when critical evolutionary changes had occurred through the use of ‘molecular clocks’.

Computers, electron microscopes and evolution

Increased experimental precision combined with vastly improved scientific instrumentation was opening up exciting new fields. In 1936 Alexander Oparin (1894–1980) demonstrated a possible mechanism for the synthesis of organic matter from inorganic molecules. In the 1960s it was determined that the Earth’s earliest life-forms treated as plants, the cyanobacteria known as stromatolites, dated back some 3.5 billion years.

Mid-century transmission and scanning electron microscopy presented another level of resolution to the structure of matter, taking anatomy into the new world of “ultrastructure”.

Biogeography, ecology, domesticated plants 1900-1950 ->

Colonial expansion had, for the colonists, made the world seem smaller and less mysterious. In the early twentieth century the traditional analytic scientific method of breaking things up into constituent parts to see how they worked began to look beyond the scale of individuals into larger groupings. In 1912 Alfred Wegener (1880–1930) published the theory of continental drift which gave impetus to more global interactions. Nineteenth century botanists like Joseph Hooker and Robert Brown had begun reasoned speculation on global plant distribution and this mode of thinking, supported by the work of people like von Humboldt, Alfred Russel Wallace and French-Italian Leon Croizat created a whole new interest in large-scale biological systems at a global scale known as biogeography.

At about the same time and at a slightly smaller scale scientists were looking more closely than ever before at the way plants and animals were interacting with one-another and their environment. This was the beginning of ecology which, by 1930,had produced the important ideas of plant and animal communities, succession, community change, food chains, energy flows and such which, from the 1940s, matured into and independent discipline as Eugene Odum (1913–2002) and others formulated many of the modern concepts of ecosystem ecology.

Genetics had provided a means to study the history and evolution of domesticated plants and the pioneering work on this subject by Frenchman Alphonse de Candolle was extended by Russian Nikolai Vavilov (1887–1943) who, from 1914 to 1940, published accounts of the geography, centres of origin, and evolutionary history of the economic plants that were now occupying so much of the earth’s surface.

The future

Research is unending: every new discovery or problem solved gives rise to more questions. But if we were to bring back Theophrastus and tell him what we have found out since he and Aristotle were researching plants and animals on the island of Lesbos, I think he would be both amazed and deeply impressed. We now know how plants work: all basic questions concerning their structure and function have, in principle, been resolved. A World Flora has begun as an inventory of all the world’s flowering plants. Although we must acknowledge forerunners it was Theophrastus, more than others, who established the ‘initial conditions’ from which so much has flowed: ideas about plant collecting and redistribution, economic botany, the botanical garden as a place associated with education (and later university), and above all the legacy of Greek analytical empiricism that gave us science in general and plant science in particular.

What would probably have surprised Theophrastus more than anything else would be the scope of modern botanical knowledge as science’s application in technology has revealed the plant world at the micro and macro scales (see Reason & science).

So what problems are left to solve: what will plant science look like in years to come, and what are the problems yet to be resolved?

Molecular biology

The fine detail revealed by microscopes of incredible sophistication, and chemical analysis that penetrates to the atoms first postulated by Democritus – the explanatory power opened up by genetics, understanding of the genetic code, and the molecular biology on which modern biotechnology rests.

Ecology

Now the distinction between pure and applied botany becomes blurred as our historically accumulated botanical wisdom at all levels of plant organisation is needed (but especially at the molecular and global levels) to improve human custodianship of planet earth. The most urgent unanswered botanical questions now relate to the role of plants as primary producers in the global cycling of life’s basic ingredients: energy, carbon, hydrogen, oxygen, and nitrogen, and ways that our plant stewardship can help address the global environmental issues of resource management, conservation, human food security, biologically invasive organisms, carbon sequestration, climate change, and sustainability.

Classical era (500 BCE-410 CE)

During the period of the Greek empire (c.500 BCE-100 BCE) medicinal knowledge passed to the Greek rhizotomi who compiled lists of plants and their medicinal properties culminating in the compilation of Diocles of Carystus in Euboeia. Especially notable from this period was the Hippocratic Corpus, a list of medicinal plants attributed to the school of Hippocrates on the Aegean island of Cos, along with the work of physicians, herbalists, and plant scientists (Aristotle and Theophrastus) based in Athens, Galen in Pergamon, and Greek soldier Dioscorides in the Roman Army whose work would dominate the Middle Ages.

General plant knowledge was accumulated in the great Roman imperial libraries at Ephesus and Pergamon on the Turkish Mediterranean coast and the library of Alexandria in Egypt, notably the multi-volume encyclopaedic Naturalis Historia of Pliny the Elder.

Early Middle Ages (c. 400-1000 CE)

Though medical knowledge persisted in the Roman Empire (c.100 BCE-300 CE) to be taken up by Christianity, it was not restricted in the Middle Ages to monastery infirmaries and the clergy. In Western Europe there were centres of medicinal knowledge at Carthage, Saragossa, urban centres in France and elsewhere.

Medical education centres remained (c. 300-600 CE) in the East at Cos, Pergamon, Alexandria, Ephesus, Antioch, and later Constantinople and Edessa. From the time of Alexander Greek influence was evident in the East, notably in Greek Aristotelian schools founded in Syria whose influence passed into Persia, Arabia and elsewhere. In the fourth century a centre for medical education was established at Edessa moving to Nisibis for a few years then to Gundeshapur in Persia. Here, it appears, was a library, university, medical school, and hospital flourishing for about 300 years until about 700 CE.^[2] While Germany, France, and England entered a phase of intellectual stagnation, this centre, which used the Syriac language, was significant for its translation of many original manuscripts of Greek philosophy into Syrian. It was Arabic translations like these that were eventually translated into Latin, and sometimes back into Greek, before being assimilated again into Mediterranean and European culture. For centuries written works referring to plants such as those of influential clerics like Isodore of Seville (c. 560-631) and German Rhabanus Maurus (c.780-856) were clearly derived from the earlier work of Theophrastus and Pliny.
The years 200 to 1400 can be conveniently divided into two historical periods. From 200 to 850-900 we see minimum technical and scientific progress with the feudal system of land management just beginning and little centralized authority. After about 850 there was a consolidation of the Carolingian empire and more stable government and societies under the monastic and feudal systems. From the 8th century there was the development of a money economy, the replacement of 2-field by 3-field crop rotation, the more general use of marl (imestone) and dung for manuring, more legumes, greater use of oats, rye, and buckwheat, the hinged flail for grain harvesting, the harrow for covering seed and weeding, the completion of the heavy iron plough, introduction of iron horseshoes and improved harness. Between 1000 and 1300 the European population doubled and populations became more concentrated in towns.^[15]

During the 600 years of the European Middle Ages, from 600 to 1200, the formal tradition of herbal lore was continued in the monasteries. Many of the monks were skilled at producing manuscripts and tending the medicinal gardens that provided the herbal medicines needed for the sick who were being cared for in the monastery dormitories. However, almost universally the works of this period looked back to, and copied directly from, works of the classical era.

The Islamic Golden Age (650-1300)

With the rise of Islam in the seventh century the torch of learning passed to the intellectual centre of Islam in Baghdad where the medicinal traditions of Greece, Iran, and India were combined. In 985 an Arab medical school, based on a revival of the best Greek medicine, was established at Salerno in Central Italy associated with the monastery of Cassimo, this being an early prototype of later European universities and their medical faculties.

People have traditionally assembled in greater numbers in the the climatically equable temperate and warm-temperate zone of the world. This is where most of the world’s botanists have been trained but where where plant diversity is generally less than the tropics which is where important and practically useful centres of genetic diversity mostly lie. This is important in the light of genetically uniform crop pan-cultivars grown as monocultures.

During the Arab Golden Age Ibn Sina (Avicenna) combined knowledge of the Greek and Muslim worlds and their scriptures into a materia medica that merged the medicinal knowledge of both East and West.

High Middle Ages (1000-1300 CE)

Development of cities and more dispersed centres of learning is indicated through the work of Albertus Magnus, a Dominica monk who, aftetr receiving his education in Padua Italy, moved to Germany and Paris his work being widely disseminated East and West in both the Arab and Christian worlds.

Late Middle Ages (1300-1500 CE)

The Late Middle Ages are marked by the advent of printing and herbals.

Sixteenth century

The 16th century opened with the first circumnavigation of the globe by the Spaniard Magellan’s expedition marking the commencement of a new phase of globalisation emanating from the nation-states of Western Europe. Seeking spices on western route across the Atlantic Ocean Columbus struck the Bahamas. Believing himself to be in the East Indies he described the native inhabitants as ‘Indians’. Columbus connected the Old World of Europe to the New World of the Americas. Travelling on an eastern route around the Cape of South Africa the Portuguese first occupied India before opening up trade routes and trading hubs to the East Indies.

Both Spain and Portugal brought Christianity to the native inhabitants, much of this work being carried out by Jesuit missionaries. But there was also interest in the study of the native plants and animals, with particular emphasis on plant medicinal properties. A general natural history of Latin America was published by the Jesuit José de Costa (1539-1600) in 1570 based on his work in Peru.

In an age of herbals Spanish versions of Dioscorides works were published and works by the Portuguese physician Amato Lusitano on blood circulation have stood the test of time, but it was the travellers who have been most remembered. Portuguese Vasco da Gama had reached Calicut on the west coast of India in 1498 and for around a century it would be Portugal that would control trade to the East. The major trading hub was Goa which was taken by Albuquerque in 1510. Physician Garcia de Orta (1501-1568) arrived here in 1534 after attending a Spanish University and lecturing in Lisbon. He is best known for his Colloquios dos Simples, e Drogas He Cousas Medicinais do India (1563) which was printed in Goa and one of the first European books to be printed in the subcontinent. A feature of his work is its coverage of popular Eastern plant products such as cloves, mace, nutmeg, ginger, cinnamon, assafoetida and betel-nut.^[11] An illustrated Spanish translation of de Orta’s book was published by Cristóvao da Costa (1515-1594) in 1578, both the original and illustrated versions achieved popularity in Europe via a Latin translation by Clusius in Leiden that included a new set of illustrations. These two works introduced Europeans to the medicinal plants of India and Southeast Asia.

Spanish botanists of the New World included Francisco Hernández, physician to Phillip II of Spain, lived for seven years in Mexico working on medicinal plants, his Plants and Animals of New Spain describes over 3000 new plants. Nicolas Monárdes (1493-1588) from Seville in his two-volume Historia Generalis Plantarum (1569, 1571) with a more comprehensive version in 1574, gives us some of the first recorded accounts and illustrations of world-transforming New World plants like tobacco and the sunflower. An English translation was published in 1577 by John Frampton an English merchant who had settled in Spain only to be imprisoned and tortured by the Inquisition but escaping from Cádiz in 1567. published on the plants of the West Indies.

Spanish physicians respected the medicinal knowledge possessed by the native Aztecs as demonstrated by the publication of Libellus de Medicinalibus Indorum Herbis (Little Book of the Medicinal Herbs of the Indians). This was a Latin translation by Juan Badiano of a Nahuatl text, the Badianus Manuscript, compiled at the Colegio de Santa Cruz in 1552 by native American Martín de la Cruz and originally written in the Nahuatl language. It has not survived in the original but it was the first scientific illustrated account of Nahua medicine and botany.

In the second half of the sixteenth century publications (their printer was Christopher Plantin of Antwerp) by Clusius, Dodoens and L’Obel all emphasised botanical detail as well as discussing native habitats and methods of cultivation.

Seventeenth century

By the 1590s Holland had become the dominant naval power in the world. In 1602 the Dutch East India Company was formed and trade extended to the Cape and India and the Far East where Batavia, modelled on Amsterdam, was founded in 1619 launching the study of economic tropical botany. Holland was ideally situated within European trade routes especially those accessing the Baltic and Mediterranean. A Dutch Golden Age followed, engaging not only military and commercial power, but science and art. In the sixteenth century Leiden had become a centre for medicine, the botanic garden, established in 1587, being one of the first in western Europe and a focus for botanical studies. There followed a series of world-renowned physicians culminating in Herman Boerhaave (1668-1738) who made Leiden the European centre for medicine. By 1630 Amsterdam was a commecial and cultural hub and in 1682 its own botanic garden was founded.

Eighteenth century

In this century it is the French legacy that stands out. The men who worked in the Muséum National d’Histoire Naturelle and Jardin des Plantes in the early nineteenth century ‘… were virtually the founding fathers of the modern natural sciences …’ and it was ‘… Frenchmen at the Jardin des Plantes rather than Britons at Oxford, Chelsea and Kew, who founded modern botany’ (Hyams & MacQuitty 1969, p. 84). This was not the case for horticulture. But some of the botanical influence that existed in Paris and London now passed to Berlin.

Nineteenth century

Germany was not a maritime power, but by the early nineteeth century communication within the network of European scientists was efficient and effective with an increasing number of specialist scientific journals. While Britain was engaged with floristics, economic botany and systematics, between 1800 and 1860 a new school of botanical thinking developed in Germany as a Renaissance in botany based in Berlin took place coinciding with Germany’s industrialization as production overtook that in France and rivalled that of Britain. Here there was a return to the microscope and the study of plant processes. Notable here is the publiscation of what was effectively the world’s first modern text book on botany by Schleiden in 1842 which finally took botany away from its procupation with plant taxonomy. Through these years in was German science that lead Europe, especially in the field of plant physiology.

Plant science

Prehistory & early civilizations – agriculture, lists, crude descriptions, materia medica, ornamental horticulture

We know little of plant study in prehistory and the early civilizations. Beyond plant use as food, specialist plant knowledge related mostly to their medicinal use. Medicine, like theology and the law, was the domain of an intellectual class. Though, from antiquity, agriculture and horticulture would have been an important part of daily life, medicine was a scholarly pursuit and therefore more likely to appear in the written record. Human health, though often associated with plant medicines, was largely a spiritual or religious matter, the preserve of a medicine man, shaman, or priest whose skills might involve sorcery, incantations, potions and spells, as well as the medicinal properties of plants. The medicine-man possessed the knowledge and skills needed for the intercession between the physical and spiritual worlds. Gradually, notably in the Classical era, began the tentative replacement of intelligent agency as a causal force in the world with that of causation operating between objects.

Classical era – plant science, medicine

Plant science, the study of plants for their own sake rather than human utility, begins and ends (for 1800 years) with Theophrastus in c. 371–287, only returning with the Renaissance revival in learning. The human preoccupation with plants for agriculture and medicine would be only briefy interrupted by this excursion into the science of Classical Greece which was lost for nearly two millennia before returning in the modern era. Even at this time plant knowledge centred around plant lists, sometimes with descriptions of medicinal properties. Romans made little advance on the botany of the Greeks but agriculture was advanced through the writings of Columella, Varro, and Palladius.

Early Middle Ages

As botany emerges out of medicine (with the plant lists appearing in materia medica, herbals, and pharmacopoias) key historical figures in this subject are also included. The list reflects the Eurocentric bias of recorded history and should be extended with the names of more plant people from Persia, China, India and the East. However, records at present do suggest that although medicine in India and China was equal to that of the West, botanical science was of little interest.

Diversification of plant science

In very general terms we see human curiosity in plants, from prehistory to the European Renaissance, centred on medicinal plants but with a brief interlude in Classical Athens when plants were studied for their own interest.

With the Renaissance medicine was transformed into botany via botanic gardens associated with the appointment of professorial chairs (Professor Simplicium) to the the medical faculties of universities. This occurred first in the affluent Italian trading city-states of Venice, Genoa, Padua ad Pisa. From here botanical science would gradually become established in botanic gardens across Europe passing from the Mediterranean to Europe’s northwest and the Atlantic coast. Students in the Middle Ages were expected to be fluent in Latin, which was the common language of learning, so personal names were frequently Latinized. Lists of plants and their properties appeared as printed Herbals in the fifteenth century but these were largely derived from early sources. Botany proper with the taxonomy and standardization that was needed to put system and order into the flood of new plants coming into Europe during the Age of Discovery. Gradually a standardized terminology for plant morphology began to emerge in the latter part of the sixteenth and early seventeenth centuries. The emergence of plant morphology and anatomy had been prompted by the need for a more reliable and widely-accepted plant taxonomy. Through the seventeenth century the advent of the microscope opened the door to detailed studies of plant anatomy. From about 1580 to 1670 there was a Dutch golden age during which Europe’s centre for medical education was at Leiden and dominated by Herman Boerhaave, Professor of Medicine and director of the Hortus Botanicus Leiden.

In the mid 18th century classifications moved from the essentialist Aristotelian mode (there are particular key characters that constitute the ‘essence’ of a taxonomic group) to a natural or materialist classification that considers the totality of characters, the overall similarities and differences without the necessity for universal common characters. Gradually in the early to mid eighteenth century specialist interest developed in particular plant groups such as fungi (mycology), mosses and liverworts (cryptogams) and we see the beginnings of experimentation in plant physiology.

Though pollen was observed in the 1640s it was only in the 1870s after the development of the optical microscope that palynology would become mainstream.

By 1850 meticulous German botany had produced a unified account of plant structure, development, and reproduction (Schleiden, Hofmeister, Braun).

Key points

• The first recorded distinction between animals and plants was made by Empedocles of Akragas in Sicily

• The first recorded ‘botanist’, in the West, was Menestor of Sybaris in Italy (c. 400 BCE)

• Theophrastus was the botanical culmination of the scientific and rational tradition of the Presocratic and later Greek philosophers

• Ionians Pre-Socratic philosopher Empedocles had envisaged biological evolution by the survival of better-adapted kinds; in contrast Greeks like Aristotle and Plato saw the natural world as a fixed scala naturae or Ladder of Life with a hierarchy of organisms

• Epicurus sought to overcome guilt and fear and to discourage the ceaseless appeasing rituals of religion through religious skepticism

• The Epicurean community enjoyed simplicity, fellowship and self-sufficiency away from mainstream society

• Epicureanism would have an impact on the later lives of Romans and can be seen in the work of John Stuart Mill, Karl Marx, and even Christianity

• In a strongly hierarchical society Epicurus treated women and slaves as equals

Macedonian Empire 334 – 323 BCE, showing the campaigns of Alexander the Great and his admiral Nearchus – the eastward extension of ancient Greek collective learning.
CC BY-SA 3.0 – Accessed 16 August 2019.
Courtesy Wikimedia Commons.