Mendelism / by R.C. Punnett.

  • Reginald Crundall Punnett
Date:
1912
Catalogue details

Licence: Attribution-NonCommercial 4.0 International (CC BY-NC 4.0)

Credit: Mendelism / by R.C. Punnett. Source: Wellcome Collection.

    34/218 page 12
    12 MENDELISM CHAP. Heredity^ as it was termed, expresses with fair accu- / racy some of the statistical phenomena relating to the transmission of characters in a mixed population. But the problem of the way in which characters are distributed from gamete to zygote and from zygote to gamete remained as before. Heredity is essen¬ tially a physiological problem, and though statistics may be suggestive in the initiation of experiment, it is upon the basis of experimental fact that progress must ultimately rest. For this reason, in spite of its ingenuity and originality, Galton's theory and the subsequent statistical work that has been founded upon it failed to give us any deeper insight into the nature of the hereditary process. While Galton was working in England the German zoologist, August Weismann, was elabora¬ ting the complicated theory of heredity which eventually appeared in his work on The Germplasm (1885), a book which will be remembered for one notable contribution to the subject. Until the pub¬ lication of Weismann's work it had been generally accepted that the modifications brought about in the individual during its lifetime, through the varying conditions of nutrition and environment, could be transmitted to the offspring. In this biologists were but following Darwin, who held that the changes in the parent resulting from increased use or disuse of any part or organ were passed on to the children. Weismann's theory involved the conception of a sharp cleavage between the general body tissues or somato¬ plasm and the reproductive glands or germplasm. The individual was merely a carrier for the essential germplasm whose properties had been determined
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