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Home , Genera Plantarum, Valerius Cordus

Integrative Biology 335 Historical Systematics University of Illinois

Remember this quote from the Introduction to IB335 — “ is at the same time the most basic and the most derived or synthetic field of biology. It is basic because a system of naming and classifying organisms is needed in order to communicate knowledge about them to others, and hence every field of biology uses the results of taxonomy. It is also the most derived field because it has no data of its own, but uses those from every other discipline, thus progressing with advances in accumulated knowledge and technology.”

Also remember that systematics and taxonomy are often used synonymously, but ‘taxonomy’ applies to the science of classification [and naming], while ‘systematics’ implies the study of evolutionary relationships. Today’s lecture is about the evolution of ‘taxonomy’ into ‘systematics’.

The system of classification used for in a particular place at a particular time reflects the: needs of people at the time level of accumulated knowledge philosophical concepts available technology of the period.

The development of classification systems has been closely tied to botanical gardens. This was enhanced with botanical exploration for gardens. Even today, many established, historical botanical gardens have major herbaria and specialized libraries.

The following six points summarize the sequential development of different methods to classify plants over time.

1. There is a strong historical background on the study of plants that has developed over time. Humans have been looking at plants since ancient times. The first classifications were utilitarian — the need to know if plants were useful for food, fiber, fuel, medicines, etc. or were poisonous or otherwise dangerous.

2. Humans have also been examining the structure of plants since at least the Ancient Greeks — floral details, etc. They noticed the amazing diversity of flowering plants, and this eventually led to ways of classifying this diversity. One way is to group plants based on form — tree, shrub, vine, herbaceous.

3. Another simple way to group plants is on one or a few simple traits, such as flower color or the number of stamens, which results in what we call an artificial or analytic system. [Classification systems have functions of identification and memorization]

4. Eventually, it was recognized that many plants that looked alike shared suites of morphological features (leaves, flowers, fruits) and should be grouped together in a classification system, and the idea of plant families and genera developed. This led to natural or synthetic systems of classification. [Note: there was no distinction between shared primitive and shared derived characters.]

5. After the publication of Darwin’s theory of evolution, biologists realized that the reason taxonomic groups shared certain suites of characteristics was because those groups were evolutionarily related to each other. Evolution provided the theoretical basis for morphological similarities. These result in phyletic or evolutionary systems of classification.

6. A major breakthrough in efforts to make systematics less empirical and more scientific was the development of cladistic theory and the construction of phylogenies that infer evolutionary relationships. Phylogenetic classification systems can be produced from these phylogenies. — From Peter Steven’s Chapter 3 in the Judd et al. textbook — “If you look at the phylogenetic trees in Chapters 7 through 9, you will see that it is possible to base classifications on them that capture precisely the clades in those phylogenies (See Chapter 2). Both phylogenies and classifications are hierarchical and are made up of groups nested within groups. However, some classifications in use today – in particular, evolutionary classifications – do not try to represent phylogenies in this way. Indeed, they are not strictly hierarchical. What they are trying to represent can be understood today only in the context of a long history stretching back before anyone had any idea about evolution. Understanding classifications thus means that we need to understand their history.”

Hunters & Gatherers — “Ancient men (or more likely women) who made their living by gathering food from the landscape were of necessity practical plant taxonomists. Through experience, they learned which plants were edible and which were not. Those people who failed to learn this distinction also failed to become our ancestors.” [Theodore Barkley] • developed at least 9,000 years ago • People have been using plants for medicinal purposes for at least 4,000 years

Ancient Greek (ca. 370—285 B.C.) Student of Plato & , knew Alexander the Great Enquiry into Plants, The Causes of Plants — 480 . FORM [Flowers. Trees, Shrubs, Herbs; ovaries superior or inferior, sympetalous corollas] Dioscorides & Pliny (1st C. A.D.) died at Pompeii (Vesuvius) — 600 Species. [Plants used in medicine; mints and umbels recognized as groups] Juliana Codex (ca. 500 A.D.) UTILITARIAN

MIDDLE AGES —Between fall of Roman Empire and the , there was Little original science or observations. The Ancients were thought to have possessed all knowledge, and their works were copied repeatedly. However, many Greek & Roman texts were translated into Arabic. Cultures in Arabia, China, Japan, India, and the Americas were flourishing at this time. • Death of Mohammed 632

Renaissance Albertus Magnus (d. 1280) teacher of Thomas of Aquinas De vegetabilis [distinguished monocots & dicots] • Dante, Chaucer, Gothic Cathedrals • Marco Polo (d. 1324) • Madeira discovered 1418, Azores 1419 • Guttenberg Bible 1455 • Christopher Columbus, 1492 [He was looking for plants!] • Magellan 1522 • Copernicus (d. 1543) • Dürer (d. 1528), Da Vinci (d. 1519), Michelangelo (d. 1564) • established in Pisa, (1543)

Herbalists—People sought originality, looked at plants, not just accepted and copied what the ancients said. Moveable type made books more widely available. Exploration brought new, unknown plants to Europe to be described. There was a need for medical information. UTILITARIAN

Otto Brunfels (1464—1534) Herbarum vivae Eicones [good drawings] Jerome Bock (1469—1554) Neu Kreuterbuck [good descriptions] (1501—1566) De historia stirpium Casper Bauhin (1560—1631) Pinax theatri botanici [6,000 species] William Turner Herball 1551 [in English] (d. 1544) Historia Stirpium [went on botanical field trips]

PRE-LINNAEAN Andrea Caesalpino (1519—1580) De plantis libri xvi HABIT [Had a herbarium, used flower and fruit characters]

• Botanical garden established in Pisa, Italy, 1543; also Florence & Padua, 1545 • Herbarium specimens first made by Luca Ghini in Italy, about 1532 • First shipment of coffee to England, 1650 • Rembrandt (d. 1669), Rubens (d. 1640) • Galileo (d. 1642) • William Harvey (De Motu Cordis, 1628) • (, 1665) • Francis Bacon (Novum Organum, 1620) • Chocolate introduced to Europe! (1657) • Isaac Newton (Principia, 1687) • Johann Sebastian Bach (1685-1750) • Antonio Vivaldi (ca. 1675-1743) • Jardin du Roi established (1635) • Chelsea Physic Garden established (1673)

J. P. de Tournefort (1656—1708) Institutiones rei herbariae, 700 genera & 10,146 species, Father of genus concept ARTIFICIAL [trees & shrubs/petals free vs. petals connate/flowers actinomorphic vs. zygomorphic]

John Ray (1628—1705) Synopsis methodica stirpium Britannicarum [A “flora” or account of plants that grow wild in a particular geographic region] Historia Plantarum, 3 volumes, 17,000 species NATURAL [Traveled extensively in Europe; used a classification system that relied on multiple characters of leaf, flower, and fruit characters — plants that looked alike were grouped together, such as monocots and dicots, also many modern plant families.]

LINNAEUS By middle of 18th C., many developments made science of ready for a person to synthesize information. People needed an easy, rapid way to identify and name plants. Travel widespread in period, advances in navigation, early microscopes, widespread use of herbarium specimens, printed books widely available, groundwork of herbalists, Bauhin, de Tournefort, Ray, and others.

Carl Linné or Carolus Linnaeus (1707—1778) (1753) 7,700 species (1754) 1,105 genera

1. Sexual system of classification — not used very long ARTIFICIAL [“floral hanky-panky”] 2. Binomial system of nomenclature — still used today [Name of genus + the specific epithet]

“ was named by the celebrated Gronovius and is a plant of Lapland, lowly, insignificant, disregarded, flowering but for a brief space—from Linnaeus who resembles it.”

• John Harrison, developed first chronometer or accurate clock, 1735 • Cook’s first voyage, 1769-1771 • Voltaire, 1694-1778 • French Revolution 1789 • Wolfgang Amadeus Mozart (d. 1791) • John Bartram, Philadelphia, sent plants to Europe between 1734 & 1765, traveled from Canada to Florida; discovered Franklinia • Lewis & Clark expedition, 1804-1806

POST-LINNAEAN FRENCH/SWISS (1727—1806) Familles des Plantes “Phenetics” [use all measurable features when making classification]

J. B. de Lamarck (1744—1829) Flore Françoise [Also hypothesized evolution through acquired characters — not scientifically correct, but did present idea that species could change over time]

A. L. de Jussieu (1748—1836) Genera Plantarum — [father of plant families] NATURAL [Developed classification scheme for planting the Jardin des Plantes in Paris; plants that look alike, based on a suite of characters, are grouped together]

A. P. de Candolle (1778—1841) Prodromus Systematis Naturalis Regni Vegetabilis “flora of the world”, 58,000 species

THEORY OF EVOLUTION (1809—1882) (1859) [Provided the theoretical bas for “natural” systems of classification; organisms that look alike do so because they are related and share a common ancestor]

George Bentham (1800—1884) and Joseph D. Hooker (1817—1911) NATURAL Genera Plantarum [7,569 genera]

• Karl Marx (Das Kapital, 1867) • Vincent van Gogh (1853-1890) • Piotr Ilich Tchaikovsky (1840-1893)

Asa Gray (1810—1888) A Manual of Botany of the Northern United States (1848, many later versions) Appointed first professor of botany in United States in 1842 at Harvard University (founded 1636)

PHYLETIC SYSTEMS Adolph Engler (1844—1930) and K. A. E. Prantl (1849—1893) PHYLETIC Die natürlichen Pflanzenfamilien

Charles Bessey (1845—1915) The Phylogenetic Taxonomy of Flowering Plants Also remember to look at Bessey’s “cactus”

John Hutchinson (1884—1972) Families of Flowering Plants, Genera of Flowering Plants

Robert F. Thorne (1920— ) A Phylogenetic Classification of the Angiospermae

Armen Takhtajan (1910— ) Flowering Plants: Origin and Dispersal

Arthur Cronquist (1919—1992) An Integrated System of Classication of Flowering Plants

Robert Sokal & Peter Sneath (1963) Principles of Numerical Taxonomy PHENETIC

Willi Hennig CLADISTIC/PHYLOGENETIC Grundzüge einer Theorie der Phylogenetischen Systematik (1950) Phylogenetic Systematics (1966) [published by University of Illinois Press]

David Swofford, Ph.D. from the University of Illinois, now at Florida State University PAUP–Phylogenetic Analysis Using Parsimony (1984-present)

Angiosperm Phylogeny Group. 2003. An update of the Angiosperm Phylogeny Group classification for the orders and families of flowering plants: APG II. Botanical Journal of the Linnean Society 141: 399 – 436.

APPROACHES TO CLASSIFICATIONS Utilitarian (Uses) Herbalists Form (habit of plant) Caesalpino Artificial (few obvious characters) Tournefort, Linnaeus Natural (overall resemblances) Bauhin, Ray, de Jussieu, de Candolle, Bentham & Hooker Phyletic (reflects evolution) Engler & Prantl, Bessey, Hutchinson, Cronquist, Takhtajan, Thorne

Note the following: With natural and phyletic systems of classification, members of a group have more in common with one another than with members of any other group.

Instead of having to record and remember the characteristics of every individual within a group, we only need to know characters of group as a whole, and note exceptions.

Natural and phyletic systems of classification are predictive and enable us to summarize knowledge