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Principles of classification

(c) It is less expensive; since it uses The natural system of classification
few observable features to group the The natural system of classification
organisms. is the system of grouping organisms
(d) This system does not require special based on natural features they have in
classification techniques or skilled common, particularly those reflecting their
personnel. evolutionary relationship. With advances
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in science and technology, the natural
Demerits of artificial system of system of classification has incorporated
classification anatomical, embryological, serological,
(a) It does not consider evolutionary physiological, and molecular characteristics
or phylogenetic relationship among in grouping organisms.
organisms. Closely related organisms
are most likely to be placed in In morden scientific techniques, the use of
different groups while unrelated DNA sequencing have revolutionalised the
organisms, such as bats and birds may understanding of evolutionary history that
be grouped together. This makes the allows more accurate classification based
system somewhat misleading because on genetic similarities.
phylogenetically organisms belonging

to one group would be expected to have Merits of natural system of
originated from a common ancestor. classification
(a) It allows organisms that are genetically
(b) It is based on only a limited number and evolutionarily related, to be grouped
of characteristics or information about in the same taxon. The evolutionary
each member. For example, organisms, relatedness increases among the
such as viruses, bacteria and some organisms down the hierarchy. This
fungi are grouped as microorganisms clearly implies that organisms grouped
because they are microscopic. This together at genus level will be more
classification system has ignored other evolutionarily related than those
features, such as their modes of feeding, grouped together at family level.

reproduction, and cell structure. Use (b) This classification system considers
of these features necessitate grouping homology of all characters of organisms
of these microorganisms in different which makes it easy to predict information
groups. about the missing links in the course of

(c) It does not allow the prediction of evolution of organisms even though there
information, hence it limits recent is no fossil evidence to substantiate the
(d) advancements in taxonomy. link. For example, some taxonomists
have predicted that flowering plants
(e) It does not incorporate new discoveries.
evolved from Pteridosperms, the seed

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