28 READINGS IN EVOLUTION, GENETICS, AND EUGENICS 
“The first effect of Darwin’s works,” says McFarland," “was to 
carry the world of science by storm, but at the same time to arouse 
intense hostility on the part of the theologians who found the theory 
of descent . . . . incompatible with the doctrines of Creation. In 
this conflict Darwin took no part, but was championed by Huxley, 
while Bishop Wilberforce led the opposition. The battle was long 
and bitter, there was much acrimonious writing on both sides, but 
the theory of descent—the doctrine of evolution—was found to be 
invulnerable and at present the theologians themselves have accepted 
it and even make use of it in their own work. 
“But as the years flew by the Darwinian doctrines began to meet 
with assaults from the scientists themselves, who, having endeavored 
to prove their validity, began to find them inadequate to the require- 
ments of expanding knowledge. The question was asked, ‘What is 
the origin of the fittest ?’? Given the fittest, we easily understand how 
it is perpetuated, but how does it arise? In the striking phrase of 
someone: ‘Natural selection might explain the survival of the fittest 
but fails to account for the arrival of the fittest!” 
Darwin’s main supporters during the most trying controversial 
period were Herbert Spencer and Thomas H. Huxley. 
Herbert Spencer (1820-1903) was an extremely able supporter of 
the general theory of evolution, but was more definitely an advocate 
of Lamarckism than of natural selection. His réle was that of a 
champion of the whole philosophy of evolution as opposed to special 
creation, and it was largely due to his forceful writings that Darwinism 
won the battle against dogmatism. Spencer tried to explain the 
structure of protoplasm (living substance) on a physicochemical 
basis. He thought of the structural units of protoplasm as compa- 
rable with the molecules of chemical compounds, each local region 
of the protoplasm in the organism being made up of different kinds of 
units, which he called ‘‘physiological units.’’ This conception of the 
physical basis of organic structure had a considerable influence in 
shaping Darwin’s ideas and was probably the basis of the latter’s 
provisional theory of ‘‘pangenesis.”” This theory was probably the 
first consistently worked out theory of the mechanics of heredity. 
It was thought that every part of the body is continually giving off its 
particular kind of units (‘‘gemmules”’) into the blood. These gem- 
mules are transported by the blood stream to all parts of the body and 
tJ. McFarland, Biology, General and Medical (The Macmillan Company, 
1918). : ; 
