In this article we will discuss about:- 1. History of Taxonomy 2. Concepts of Taxonomy 3. Modern Trends.
History of Taxonomy:
The development of a scientific theory of classification is probably a recent phenomenon. There is no doubt that Aristotle (384-322 B.C.) was the father of classification. According to Aristotle “Animals may be characterised according to the way of living, their actions, their habitats and their bodily parts”. He referred to such major groups of animals like birds, fishes, whales and insects.
He used differentiating characters such as blooded versus bloodless, two-footed versus four-footed, hairy versus feathered etc. Although Aristotle’s thinking dominated animal classification for the next 2,000 years, nevertheless he failed to supply an orderly, fully consistent classification.
Concepts of Taxomomy:
In 1975 Mayr and Ashlock first put forward the concept of Micro-taxonomy. Development of the debates on the species, centering mainly around the so-called biological species concept, was called micro-taxonomy or the science of species by Mayr (1982).
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One of the major problems of micro-taxonomy evolves around the concept of species. A merging of different research traditions, in systematics as well as in palaentology and genetics, prompted the development of micro-taxonomy. Micro-taxonomy involves the study of concepts of species like Typological species concept, Nominalistic species concept, Biological species concept, Evolutionary species concept etc.
Micro-taxonomy deals with problems like the evolution of species, estimation of the population of species in the living world or in special groups of organisms to which any two, three or all species definitions apply.
It also deals with geographic variation, the recognition of polytypic species, the definition of subspecies and species, the taxonomic status of incipient species and the role of non- morphological characters in the delimitation of species. In any case, the biological distinction is primary and the morphological difference secondary.
Macro-taxonomy is the science of classification:
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Theoretical comments ranged from a denial that supra-specific taxa were natural entities, to vague statements that a phylogenetic classification is the more natural. How do we reconstruct phylogeny? How do we represent it in a formal classification? These were the problems being dealt under macro-taxonomy. Macro-taxonomy involves study of homology, analogy, affinities, systematic status and phylogeny.
Micro-taxonomy and Macro-taxonomy are related in the sense that one is incomplete without the other. For the science of classification of species it is very important to know the science of species. Macro-taxonomy involves the establishment of equivalent basis of their features. So how is grouping (Macro-taxonomy) possible without knowing the features of the object (Micro-taxonomy). Hence one is heavily dependent on the other.
Modern Trends in Taxonomy:
The term new or modern is a relative term, as what is considered new or modern today may become old systematics in the future. The new systematics introduced by Hyxley in 1940 may indeed be very old systematics today. To dispel such misinterpretation of new systematics the words of Mayr (1964) is of immense help.
Mayr wrote “What then is the new systematics? Perhaps it is best described as a view-point, an attitude, a general philosophy. It started primarily as a rebellion against the nominalistic typological and thoroughly non-biological approach of certain, alas all too many, taxonomists of the preceding period”.
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The New Taxonomy, thus, is an approach of the population taxonomists that differ drastically from the simple pigeonholing of classical Linnaean taxonomy. Workers in the new systematics consider themselves biologists rather than filing clerks.
New Taxonomy is neither a special technique nor a special method but an attitude which can be applied at every taxonomic level. It deals with –
1. The utilisation of an ever-increasing number of characters and a continued depreciation of key characters — in contrast to the typological approach.
2. A ready acceptance of new tools and techniques such as —
(a) Visual analysis of sounds in insects, frogs and birds,
(b) Analysis of courtship displays and other behaviour,
(c) Utilisation of biochemical characters,
(d) Utilisation of computers.
3. A further clarification of concepts, such as
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(a) Clear separation of taxon from categories,
(b) Recognition of the subspecies as a category and not as an evolutionary unit, and
(c) Clean understanding of the causes of similarities and differences between taxa.