Artificial, Natural & Phylogenetic System Of Classification

History Of Different System Of Classification

Various attempt made to classify the plants fall in one of the following in three categories.

·        Artificial system of classification

·        Natural system of classification

·        Phylogenetic system of classification

Artificial system of classification: the earliest system of classification were artificial system and the system of this nature remained dominant from 300 BC upto 1830 AD. Since vary little information was available about plants these system were based on one or few character. The artificial system proposed by early herbalist were based on habit, trees, shrub, herbs and Linnaeus sexual system on floral character.

Theophrastus: (370-287 BC) A Greek naturalist who is called is father of botany. He was the student of great philosopher Plato and Aristotle. He classified the plants into four group on the basis of their habit that is herbs under shrub and trees. He gave name and description to some 500 plants in his book (Historia Plantarum). The oldest botanical work in existence because a wide use his name received general recognition and some of them still appeared as generic name in modern classification for instance. 

E.g Aspharagos (Greek)  ↔  Asparagus (Latin).

He pointed out fundamental difference between monocotyledon and dicotyledon and also recognized difference types of insertion of floral appendages, Thus so lying out foundation for the study of floral morphology.

Angera Caisapina (1519-1603) He was first plant taxonomist and Italian botanist director of botanical and professor of botany in Bologna university. He went to Rome in 1592 as a personal physician of Pop.

Gasspard Bauhin (1560-1624) He was Swedish botanist (1st generic name and 2nd species name this idea gave by them).

John ray (1627-1705) English botanist he was head of padiest.

Carolus  Linnaeus (1707- 1878) He was consider father of botany, 24 classes of classification gave be them, books written by them (species plantarum and generic plantarum)

Natural system of classification: The 2nd half of the 18th century was a period when great number of living plants, seed plants and collection of prepared specimen was coming to European botanical institution from all over the world. A large proportion of these were of species new to science each was to began a name to be describe and place in classification. Preparation of flora  the realization that there were great nature affinities / linking  between plants then the so called sexual system of Linnaeus would indicated.

This realization was not derived from theory and philosophy or logic but was made by means of increase knowledge and understanding of the organography / morphology of the plants. Microscopy was invented in these period, function of plants also noted and help of microscopy new system were called natural system. And they were so in the sense that they reflected means understanding of nature at their time. The plants were placed together existed a correlation of character in common.

Natural System Of Classification

Augustin Pyramus de Candolle system of classification

Ø Vascular plants with vascular bundles and cotyledons.

Exogene: dicotyledons, vascular bundles are arrange in a ring

Endogene: monocotyledon vascular bundle are scattered on the ground tissue .

Ø Celulares plants without vascular bundles.

Foliaceae: leafy sexual plant include mosses and liverworts.

Aphillar: leafless, algae, fungi and lichen

 

Bentham and Hooker Natural system of classification

George Bentham 1800-1884,josep-dalton hooker 1817-1911 two british botanists were associated with royal botanical garden kew at london. They jointly produce  a book genera plantarum 1862- 1883 completed this book.

Classification of Bentham and hooker

1.       Polypetalea: 82families include these are group of dicotyledon

2.       Gamopetalae: 45 families include

3.       Monochlamydeae: 36 families lower plants include.

4.       Gymnosperm: 3 families include

5.       Monocotyledon: 4 families include.

Phylogenetic system of classification

The outlook of taxonomy was changed with the publication of origin of species through natural selection by Darwin in 1859 ,24 November. Every copy of 1st edition was sold on the first day of 24 November 1859 which revolutioned biological thinking. The system of this period are based on the course of evolutionary descent and try to reflect the genetic and phylogenetic relationship. The most widely known system of this period are those of Engler  and Prantl both was German scientist.

John Hutchinso: 1884 -1930 belong to England royal botanical garden .

Two modern systems Arman Takhthan Jaan 1911-1997 authur cronquest 1919-1992 his system of classification was published in fully documented form Coloumbia university USA.

Engler and prantel the two german botanist publish a twenty volume work.

Die naturalichen pflanzan families 1887-1899 published this book where in classified the plants of the world from algae to angiosperm according to their system of classification.

This system has gone undersome changes in syllabis der pflanzen families one volume book which were published in several edition.

The 12th edition appeared  in 1964.

Angler and prantle system of classification is as important as that of benthum and hooker.

The system of classification published in following heading.

1.     Metachlamydeae

2.     Archechlaymdeae

3.     Apetalae

Metachlamydaea fused carpel includes gamopetlous form where aa archeclamydeae into polypetlous form.

The polypetlos form were included in chloropetale and Apetale [without petals].

Each subclass is divided into orders and ordes are composed of group related families.