scopeofzoology

Zoology has never been synonymous with taxonomy. Its province has always been that of
animal biology in its widest context. For example, a zoologist may want, first of all, to find out
how a particular animal works, considered as a piece of living mechanism, and to compare
the ways of working of various other animals. This is the field of animal physiology with the
emphasis on comparisons. Secondly, he may want to know all he can about the structural
plans of animals, to know how that structure develops and to compare the structure of
different animals. That is animal morphology - the science of form. Finally, he may want to
understand how and why it is that different individuals and species of animals are what they
are; their history and as much as possible about the causes of their history. That is the field
of animal heredity and evolution.
The uniqueness of the zoologist as he stands amongst other biologists is that he seeks to
interpret findings about the life of animals within the framework of the theory of evolution.
Evolution is the term used to describe the process by which man arose, by an infinitesimal
slow progression, from a level of organisation similar to that of present-day micro-organisms.
As far as we know, the most important mechanism in the evolution of living species is that of
natural selection. Natural selection suggests that if any form of stress is put on a population
of living creatures, those which most effectively respond to the stress will survive and those
which respond less effectively will die. Survivors pass on their successful characteristics,
which we term 'adaptations', to their descendants. Unsuccessful characteristics are
eliminated through a failure in reproduction and the nature of the population changes. This
leads the zoologist to examine the adaptive significance of his findings, whether they be at
the population or molecular level. In other words, he wishes to know how the structure or
function he has discovered has been advantageous in promoting the evolution of the animal
possessing it. In answer to the question "Why does the tiger have claws?", the molecular
biologist would say that physico-chemical conditions exist at certain point in the embryo
which make it inevitable that certain living cells there will produce the special hard substance
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