118 “The Descent of Man” 
corrected. A large ear with a point is shown in the photograph’, 
but it can easily be demonstrated—and Deniker has already pointed 
this out—that the figure is not that of an orang-foetus at all, for that 
form has much smaller ears with no point; nor can it be a gibbon- 
foetus, as Deniker supposes, for the gibbon ear is also without a 
point. I myself regard it as that of a Macacus-embryo. But this 
mistake, which is due to Nitsche, in no way affects the fact recognised 
by Darwin, that ear-forms showing the point characteristic of the 
animal ear occur in man with extraordinary frequency. 
Finally, there is a discussion of those rudimentary structures 
which occur only in one sex, such as the rudimentary mammary glands 
in the male, the vesicula prostatica, which corresponds to the uterus 
of the female, and others. All these facts tell in favour of the 
common descent of man and all other vertebrates. The conclusion 
of this section is characteristic: “Jt is only our natural prejudice, 
and that arrogance which made our forefathers declare that they 
were descended from demi-gods, which leads us to demur to this 
conclusion. But the time will before long come, when at will be 
thought wonderful that naturalists, who were well acquainted with 
the comparative structure and development of man, and other 
mammals, should have believed that cach was the work of a separate 
act of creation?.” ; 
In the second chapter there is a more detailed discussion, again 
based upon an extraordinary wealth of facts, of the problem as to 
the manner in which, and the causes through which, man evolved 
from a lower form. Precisely the same causes are here suggested for 
the origin of man, as for the origin of species in general. Variability, 
which is a necessary assumption in regard to all transformations, 
occurs in man to a high degree. Moreover, the rapid multiplication 
of the human race creates conditions which necessitate an energetic 
struggle for existence, and thus afford scope for the intervention of 
natural selection. Of the exercise of artificial selection in the 
human race, there is nothing to be said, unless we cite such cases as 
the grenadiers of Frederick William I, or the population of ancient 
Sparta. In the passages already referred to and in those which 
follow, the transmission of acquired characters, upon which Darwin — 
does not dwell, is taken for granted. In man, direct effects of 
changed conditions can be demonstrated (for instance in regard 
to bodily size), and there are also proofs of the influence exerted 
on his physical constitution by increased use or disuse. Reference is 
here made to the fact, established by Forbes, that the Quechua- 
Indians of the high plateaus of Peru show a striking development 
1 Descent of Man, fig. 3, p. 24. 2 Ibid. p. 36. 
