scopeofzoology

With the establishment of the theory of evolution in the latter part of the l9th century, which
stressed temporal changes in the organisation of living things, taxonomy gradually became
concerned with the relationship or kinship of animals to each other. During this period,
taxonomy began to express not merely a convenient cataloguing of animals according to
structural differences and similarities, but also took into account the ancestral relationships
between them. Study of the diversity of organisms with a view to establishing relationships
between them is termed 'systematics' and at this time the terms 'taxonomy' and 'systematics'
were generally considered to be synonymous, and dealt mainly with the progressive
evolution of the anatomical features of animals.
This approach also dominated British zoology in the first quarter of the 20th century when it
was almost wholly occupied with problems of phylogeny and comparative anatomy; that is
with the apportioning out of evolutionary priorities and the unravelling of relationships of
descent. Comparative anatomy has many brilliant discoveries to its credit; at best,
exemplified by the deduction that the bones in the mammalian ear, which transmit vibrations
from the eardrum to the organ of hearing, are cognate with bones of ancestral organisms
which had formed part of the articulations of the lower jaw. These discoveries and others
equally dramatic showing modifications with evolution, were the product of the l9th century.
Studies in the early 20th century were concerned with refining and correcting basic
discoveries made earlier. All of the great successes of comparative anatomy were achieved
before the turn of the century and nearly all of the great dynasties in the evolutionary history
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