The Genetic Behaviour Of A Secondary Sexual Character

Author : T. H. Morgan
Publisher :
ISBN 13 : 9781332788644
Total Pages : 138 pages
Book Rating : 4.7/5 (886 download)

DOWNLOAD NOW!

Download or read book The Genetic and the Operative Evidence Relating to Secondary Sexual Characters (Classic Reprint) written by T. H. Morgan and published by . This book was released on 2016-06-27 with total page 138 pages. Available in PDF, EPUB and Kindle. Book excerpt: Excerpt from The Genetic and the Operative Evidence Relating to Secondary Sexual Characters There are a few races of poultry that have two kinds of males, one with the feathering of the ordinary cock, the other with the feathering of the hen. The Hamburgs and the Campines are perhaps the best known races of this sort. Convention amongst breeders, in certain countries, has determined that the cock-feathered bird shall be the standard, and at other times and places that the hen-feathered males shall be the show birds. In one breed, at least, viz, the Sebright bantams, the hen-feathered cock is the only known type. Cock feathered Sebrights have never been seen, so far as I know. This breed is pure for hen-feathering. As shown in plate 1, figure 3, the male Sebright lacks the long, pointed saddle feathers at the base of the tail of the common cock, also the peculiar back and neck feathers (hackles) of the cock bird, as well as the male feathering on the bow of the wing. His feathers in these parts are almost exactly like those of the hen (plate 4, fig. The long Sickle feathers covering the true tail are also absent, although the two median ones sometimes occur in males of this race. The Sebrights seemed excellent material for studying the heredity of this type of plumage in the male. In 1911 I began to study this problem, and crossed Sebrights to black-breasted Game bantams. The latter race was chosen not only because the males have the typical cock-feathering, but also because the coloration of these birds resembles very closely that of the jungle-fowl, from which many, perhaps all, of our domesticated races have sprung. 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 technology 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.