Question

What's the contribution of these scientists to taxonomy AP De condolle,

Bentham and hooker, Earnst Haeckel

Answer 1

Augustin Pyramus De Candolle contributed the De Candolle system as a system of plant taxonomy. Candolle’s criteria provided the empirical foundation for a modern evolutionary history of plants. His system of plant classification found nearly universal application for half a century, during which time it served as a model for other systems.

Bentham And Hooker- The most accepted natural system of classification of seed plants (Phanerogams) was jointly proposed by two British Botanists, George Bentham and Sir J.D. Hooker in three volumes of Genera Plantarum (1862 – 1883), published in Latin.The classification was based on the form relationship and plant characters which could be correlated with each other. The system was based on the classification of A.P. de Candolle and Lindley, which followed de Jussieu’s classification, but differed and refined from them in many aspects. It is one of the most popular systems of classification followed in many herbaria of the world even today. The classification was based on an actual study of the plant specimens and was not compiled from the work of the earlier authors. This made it a very accurate, authentic and popular classification. They provided key characters for the families and genera which was an easy aid for identification.The seed plants or Phanerogams were divided into three classes – Class I: Dicotyledons, Class II: Gymnosperms and Class III: Monocotyledons. Each class is further divided into subclasses, each subclass into series, cohorts (modern orders) and orders (modern families). Ernst Haeckel (1834–1919) and August Wilhelm Eichler (1839–18878) were two German biologists who started the construction of evolutionary trees. Haeckel established the term "phylogeny". The main part of the 20th century was dominated by extended phenetics, i.e. looking for similarities and differences to create systematics. Not only gross morphology was used to find characters, but anatomy, chromosomes, pollen, biochemistry and eventually proteins. The systems of plants and animals were now huge, in flowering plants approaching a quarter of a million species.