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Taxonomy
Year 1998InfoAuthor: Qjure
Taxonomy is the science of classification or categorization. It can be done for minerals, plants, animals, and so on.Botanical classification have be made for millenia. They have been based on different characteristics. In earlier times systems were just lists of medical plants. Emperor Shen Nung classified herbs based on their medical qualities. Ebers medical papyrus from Egypt is also a systematic arrangement of medicinal plants. Later plants were also sorted by habitat.
The first true systems arose in the late 16th century and in the 17th century. Initially the classification was very simple with as divisions: tree, shrub and herb. Later subshrub was added. But the amount of plants available from herbariums exploded. Andrea Cesalpino introduced the idea of dividing plants by fruits.
A major step was Species Plantarum by Carl Linnaeus in 1753. He introduced the binomial nomenclature, the naming of plants with 2 words, the genus and the species. This standardised the naming of plants. His classification of plants on the amount of stamens was less effective.
Michel Adanson introduced a multi-characteristic taxonomy, based on many qualities and not only the flowers, like Carl Linnaeus. It introduced a much more natural system, with more precise groupings.
The Jussieus combined the groupings of Adanson into a system that lasted with small adjustments for 200 years. A natural method of the classification of plants was established. The term Taxonomy became standard.In the 19th century botanists took on the the idea of evolution. Adolphe-Théodore Brongniart started working with fossils, and Eichler used that as a good fundament for his system. In the 20th century the evolution based taxonomy, arranging taxa in an evolutionary tree. It became known as Cladistic Taxonomy, or cladistics or cladism. Monophyly, the principle that a taxon includes all the descendants of some ancestral form and only those ones, became a guiding principle. The relation between plants was no longer based on their look.
The introduction of DNA analysis became used to reveal the plants ancestors. A strong tendency arose to based the taxonomy on evolution alone.DiscussionThe phylogentic classification, based on DNA, has much resemblance wit the older taxonomies based on from and chemical contents. But some old groups are split and others are joined. Quite some confusion has been created by disappearance of
classes, families and orders, by the creation of new classes, by the changing of names of orders, classes, by changing their endings.
In some cases the DNA taxonomy and the form taxonomy seem very contradicting. Some plants are split into two, and even placed in different families based on their DNA, whereas their form is totally identical. In other cases plants are placed near to each other, whereas their form is totally different. For instance Platanus and Nelumbo are closely related in the DNA taxonomy.
The first true systems arose in the late 16th century and in the 17th century. Initially the classification was very simple with as divisions: tree, shrub and herb. Later subshrub was added. But the amount of plants available from herbariums exploded. Andrea Cesalpino introduced the idea of dividing plants by fruits.
A major step was Species Plantarum by Carl Linnaeus in 1753. He introduced the binomial nomenclature, the naming of plants with 2 words, the genus and the species. This standardised the naming of plants. His classification of plants on the amount of stamens was less effective.
Michel Adanson introduced a multi-characteristic taxonomy, based on many qualities and not only the flowers, like Carl Linnaeus. It introduced a much more natural system, with more precise groupings.
The Jussieus combined the groupings of Adanson into a system that lasted with small adjustments for 200 years. A natural method of the classification of plants was established. The term Taxonomy became standard.In the 19th century botanists took on the the idea of evolution. Adolphe-Théodore Brongniart started working with fossils, and Eichler used that as a good fundament for his system. In the 20th century the evolution based taxonomy, arranging taxa in an evolutionary tree. It became known as Cladistic Taxonomy, or cladistics or cladism. Monophyly, the principle that a taxon includes all the descendants of some ancestral form and only those ones, became a guiding principle. The relation between plants was no longer based on their look.
The introduction of DNA analysis became used to reveal the plants ancestors. A strong tendency arose to based the taxonomy on evolution alone.DiscussionThe phylogentic classification, based on DNA, has much resemblance wit the older taxonomies based on from and chemical contents. But some old groups are split and others are joined. Quite some confusion has been created by disappearance of
classes, families and orders, by the creation of new classes, by the changing of names of orders, classes, by changing their endings.
In some cases the DNA taxonomy and the form taxonomy seem very contradicting. Some plants are split into two, and even placed in different families based on their DNA, whereas their form is totally identical. In other cases plants are placed near to each other, whereas their form is totally different. For instance Platanus and Nelumbo are closely related in the DNA taxonomy.