 | Charles Darwin - 1876 - Страниц: 544
...domesticated animals, in the same manner, though in a far less degree, as with captive wild animals. It is by no means rare to find certain males and females...be perfectly fertile with other males and females. Wo have no reason to suppose that this is caused by these animals having been subjected to any change... | |
 | John Michels (Journalist) - 1886 - Страниц: 720
...reproductive system.' Of this fact we have evidence in individuals (eg, Mr. Darwin observes that " it is by no means rare to find certain males and females which will not breed together, though both arc known to be perfectly fertile with other males and females"), in races (eg, under domestication,... | |
 | Alfred Russel Wallace - 1889 - Страниц: 520
...species, and the fertility of the offspring thus produced. Among domestic animals, Darwin states that it is by no means rare to find certain males and females which will not breed 1 Darwin's Animals and Plants under Domestication, vol. ii. pp. 163-170. together, though both are... | |
 | Charles Darwin - 1890 - Страниц: 532
...domesticated animals, in the same manner, though in a far less degree, as with captive wild animals. It is by no means rare to find certain males and females...been subjected to any change in their habits of life ; therefore such cases are hardly related to our present subject. The cause apparently lies in an innate... | |
 | Conwy Lloyd Morgan - 1891 - Страниц: 542
...The same is not true, however, of differential fertility. "It is by no means rare," said Darwin, f "to find certain males and females which will not...be perfectly fertile with other males and females." Mr. Eomanes assumes, as a starting-point, the converse of this, namely, that certain males and females... | |
 | Charles Darwin - 1892 - Страниц: 558
...animals, in the Fame manner, though in a far less degree, as with captive wild animals. It is by no moans rare to find certain males and females which will...be perfectly fertile with other males and females. Wo have no reason to suppose that this is caused by these animals having been subjected to any change... | |
 | Charles Darwin - 1896 - Страниц: 734
...domesticated animals, in the same manner, though in a far less degree, as with captive wild animals. It is by no means rare to find certain males and females...be perfectly fertile with other males and females. Wo have no reason to suppose that this is caused by these animals having been subjected to any change... | |
 | Charles Darwin - 1898 - Страниц: 522
...domesticated animals, in the same manner, though in a far less degree, as with captive wild animals. It is by no means rare to find certain males and females...be perfectly fertile with other males and females. Wo have no reason to suppose that this is caused by these animals having been subjected to any change... | |
 | Alfred Russel Wallace - 1901 - Страниц: 542
...species, and the fertility of the offspring thus produced. Among domestic animals, Darwin states that it is by no means rare to find certain males and females which will not breed 1 Darwin's Animals and Plants under Domestication, vol. ii. pp. 153-154 and 163-170. together, though... | |
 | Robert Alexander Gibbons - 1923 - Страниц: 270
...nature. INCOMPATIBILITY. Incompatibility is observed all through the animal world. According to Darwin, it is by no means rare to find certain males and females which will not breed together, though they are known to be perfectly fertile with other males and females. He considers that the cause, apparently,... | |
| |
It is by no means rare to find certain males and females which will not breed together, though both are known to be perfectly fertile with other males and females. 
