Genetics - Second Edition

By: Karvita B. Ahluwalia...

Man’s curiosity to know about transmission of hereditary characters is as old as humanity itself. From the earliest times it had been noticed that the offspring may resemble their parents, grandparents, or other relations. Around 300 BC the great Aristotle had observed that peculiarities of hair, nails and even gait may reappear in offspring, that characters not visible in an individual may also be inherited. It appears that the existence of heredity was taken for granted. Yet, the rules which govern transmission of characters were not understood. Explanations were sought everywhere, even in the prevailing beliefs of the time such as magic,
witchcraft, gods and folklore.

Many considered heredity to be some sort of a blending process, because of which the offspring showed different ‘‘dilutions’’ of the parental characteristics. The concept of blending inheritance
fitted well with ancient thinking as it could explain why some children were more like their parents whereas others were less. As far back as 400 BC an ancient Greek writer suggested the role of environment in producing variations in inheritance. The idea appears similar to the ‘‘Theory of acquired characteristics’’ proposed by Lamarck twenty-two centuries later.


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