Heredity of Hair-Length in Guinea-Pigs and Its Bearing on the Theory of Pure Gametes, And, the Origin of a Polydactylous Race of Guinea-Pigs (Classic Reprint) by William E Castle (Paperback / softback, 2015)
Excerpt from Heredity of Hair-Length in Guinea-Pigs and Its Bearing on the Theory of Pure Gametes, And, the Origin of a Polydactylous Race of Guinea-Pigs In earlier papers (Castle: 03: 05) it has been shown by one of us that long or Angora coat in guinea-pigs and rabbits is alternative in heredity to rmal or short coat. It has been shown further that in cross-breeding rmal or short coat dominates over long coat, in conformity with Mendel's law of heredity, but that the purity of the gametes formed by cross-breds is t absolute. Impurity of the gametes is indicated by two facts: First, the number of long-haired young produced by cross-bred parents is in excess of the Mendelian proportion, one-fourth; secondly, many of these long-haired young show an imperfect development of the long-haired character, as compared with their long-haired ancestors. Both these facts may be explained by supposing that the alternative characters, short and long hair, which are present in the cross-breds - one seen, the other unseen - have in many cases failed to segregate, or have segregated only imperfectly, when gametes have been produced by the cross-breds. Accordingly the conformity with Mendel's law is a qualified one. More extended and detailed studies made by us during the past year confirm these conclusions and add several new facts concerning the behavior in heredity of these alternative characters. The idea advanced tentatively by Castle (:05), that the hair-lengths of guinea-pigs form a discontinuous series of two, three, four or more times the length of short or rmal hair, is found to be incorrect. Careful examination of the hair of several hundred guinea-pigs (mostly cross-breds) shows that there occur hairs of practically all lengths from 3.3 cm. up to about 23 cm. The series of supposed maximal hair-lengths of twice 4 cm., thrice 4 cm., etc., resulted from an insufficient number of observations. About the Publisher Forgotten Books publishes hundreds of thousands of rare and classic books. Find more at www.forgottenbooks.com This book is a reproduction of an important historical work. Forgotten Books uses state-of-the-art techlogy to digitally reconstruct the work, preserving the original format whilst repairing imperfections present in the aged copy. In rare cases, an imperfection in the original, such as a blemish or missing page, may be replicated in our edition. We do, however, repair the vast majority of imperfections successfully; any imperfections that remain are intentionally left to preserve the state of such historical works.