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Natural History, Taxonomy, and Systematics

The last 300 years or so, or until I run out of time

Some Definitions

• Natural History – the study of the constituents of nature, their relationships with each other, and their respective places in the overall order of nature.

• Systematics – The study and construction of systems of classification.

• Taxonomy – The study and practice of filing things into a system of clasification.

Aristotle (384-322 BC)

Logical dichotomous division

Living genus

Plant Animal species/genus

Tree Shrub species

But that is not how Aristotle classified living things.

Historia Animalium

Botanical Practices of the Ancients

Theophrastus (371-287 BCE)

Dioscorides (ca. 60CE) Materia Medica

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The Herbalists

Medieval and Renaissance

Classification based on use

HerbsMedicines Food PlantsOilsDyes

No unified system

The Great Chain of BeingScala Naturea

John Ray (1627 – 1705)

Described over 18,500 plant “species”

“The first condition of a natural method must be that it neither splits plant groups between which apparent natural similarities exist nor lumps such with natural distinctions”

Natural Method / Artificial System

Similarity based on characters

Which characters?

Instramentalist approach

Joseph Pitton de Tournefort (1656-

1708)

“To know the plants is to know the exact names one has given to them on the basis of the structure of some of their parts.”

Criticized Ray for inconsistent use of characters

Formulation of genus concept

Described 698 genera – most adopted by Linnaeus

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Carl von Linné (1707 – 1778)

1735 – Systema Naturae

Established a unified foundation for the practice of botany

Linnaean hierarchy

Sexual system

Formalized Nomenclature

Binomial Latin Names Carolus Linnaeus

Generic reform

Formalizing Nomenclature

• International Botanical Congress (1905)

– Species Plantarum (1753)

• International Commission on Zoological Nomenclature (1892-1905)

– Systema Naturae 10th ed. Vol. 1 (1758-1759)

Linnaean Hierarchy

KingdomPhylum

ClassOrder Genus

Species

Modern Taxonomic Hierarchy: Botany

primary ranks- - -secondary ranks- - - - - - -

further rankskingdom (regnum)- - - - - - -

subregnumphylum (phylum)- - - - - - -

subphylumclass (classis)- - - - - - -

subclassisorder (ordo)- - - - - - -

subordofamily (familia)- - - - - - -

subfamilia- - -tribe (tribus)- - - - - - -

subtribusgenus (genus)- - - - - - -

subgenus- -

section (sectio)- - - - - - -subsectio- - -

series (series)- - - - - - -

subseriesspecies (species)- - - - - - -

subspecies- - -variety (varietas)- - - - - - -

subvarietas- - -form (forma)- - - - - - -

subforma

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Works of Linnaeus

• 33 Principal works

• 186 Dissertations/theses

– (1741 – 1776)

• Multiple editions of several works

– Systema NaturaeWent from 11 – 3000 pgs.

Philosophia Botanica

“151. The FOUNDATION of botany (4) is two fold, arrangement and nomenclature. …

Knowledge of botany bears on these hinges; thus all plants become known in a single year, at first sight, with no instructor and without pictures and descriptions, by means of stable recollections. „Ergo, qui hoc novit, Btanicus est, alius non.‟ ”

Translated by Stephen Freer, 2003.

A Taste of Linneaus

“216. The generic must be the same

within the same genus.”

“221. Generic names made from two

entire and separate words are to be

banished from the Commonwealth of

Botany.”

“249. Generic names 1½ feet long,

those that are difficult to pronounce or

are disgusting, should be avoided.”

“268. Taste is often variable, according

to the person doing the tasting;

therefore it should be excluded from

definitions.”

“330. A description may be longer or

shorter than it should be: Either is

wrong.”

The Swedish Empireca. 1658

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Much like the EnglishLove their Newton…

Linnaeus and the Natural Method

Species

Genera

Higher Rank

Georges-Louis Leclerc, Comte de Buffon (1707-1788)

Chief opponent of Linnaeus

All classification was inherently artificial

The only “real” category was the species indentified by membership in a common breeding community

Histoire Naturellle

Michel Adanson (1727 – 1806)

Use of multiple characters

Equal weight to all characters

Overall similarity

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Early 19th Century Taxonomy

Georges Cuvier (1769-1832)

Correlation of characters

Jean Baptiste Lamarck (1744-1829)

Tree thinking

Antoine Laurent de Jussieu (1748-1836)

Subordination of characters

Fixed, Changing, or Evolving

Darwin and Classification

“Thus on the view which I hold, the natural system is genealogical in its arrangement, like a pedigree; but the degrees of modification which the different groups have undergone, have to be expressed by ranking them under different so called genera, sub-families, families, sections, orders and classes.”

DARWIN’S TREES

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David Hull

Professor Emeritus Northwestern University Philosophy

1964 Indiana University, PhD - The Logic of Phylogenetic Taxonomy

Former President – PSA, Society of Systematic Zoology, ISHPSSB

Associate Editor, Systematic Zoology1975-1982

Science as a Process (1988)The Modern Synthesis

Population Genetics, Systematics, Palentology, Evolutionary Biology

Three Groups of Three:

R. A. FisherJ. B. S. HaldaneSewall Wright

Theodosius DobzhanskyGeorge Gaylord SimpsonErnst Mayr

Julian HuxleyC. D. DarlingtonE.B. Ford Evolution: The Modern Synthesis

(1942)

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Evolutionary Systematics

Julian Huxley – The New Systematics, 1940

Mayr – Simpson

Biological Species Concept

Phylogeny reconstruction based on inferences of evolutionary process

Detecting evolution at work -Huxley

Systematics is both a science and an art-Simpson

1902 - 1984

1904 - 2005

Numerical Taxonomy (Phenetics)

Principles of Numerical Taxonomy, Sokal and Sneath, 1963

Overall similarity

Neo-Adansonians

Methods must be objective, explicit, quantitative, and repeatable

Robert Sokal

Phylogenetic Systematics (Cladistics)

Gründzuge einer Theorie der Phylogenettischen Systematik, Willi Hennig, 1950

Phylogenetic Systematics, Hennig (translated by Davis and Zangler), 1966

Nested sets of monophyletic groups diagnosed by the discovery of synapomorphies.

Cladograms as hypotheses

Fundamental, methodological principles

A Taxonomy of Systematists

Phenetics

Evolutionary Systematics

Cladistics

Pattern Cladists

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Natural Selection in 9th Grade Biology

Variable set of characters with in a population

Transfer those characters to the next generation through reproduction

Random mutation

Selection

Genes mutate - Organisms are selected - Species Evolve

Science as a Selection Process

Variation in conceptualization of core ideas with in a research group

Transfer of those characters to the next generation

Change in ideas, theories, research methods, etc.

Selection pressure from journals, professional societies, and funding

Evo

lutio

na

ry

Pro

ce

ss

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But,

What

About

…?