182 THE TREND OF THE RACE 
We often find it stated that in mankind natural selection has 
been practically done away with by our advances in civilization. 
We no longer 4 live in fear of wild beasts; human beings seldom 
die of starvation or succumb to the direct effects of climate. We 
endeavor to keep alive the weaklings who would perish under a 
more primitive régime. Everything is done which is rendered 
possible by our knowledge and skill to prevent natural selection 
from eliminating the ill-favored members of our race. 
Nevertheless the operation of natural selection is far from 
completely checked. However far science may advance, it will 
always lie beyond our power to do away entirely with its action. 
Dr. G. A. Reid in his Present Evolution of Man maintains that 
man’s advance “‘is not mainly an evolution of physical or intel- 
lectual strength, as in his remote ancestry, but mainly an evolu- 
tion against disease.” While there are several evolutionary 
factors which Dr. Reid has not considered in his book, he is doubt- 
less correct in his contention that the course of our development in 
the past has been greatly influenced by the selective action of 
various diseases, and that it will probably continue to be so in the 
future. Races tend, through the action of natural selection, to 
become immunized to prevalent diseases. Most diseases act 
much more severely upon some individuals than others. Many 
people are practically immune to certain diseases, and some races 
are more or less immune to diseases which in other races have a 
high fatality. The relative immunity of the negro race to malaria 
is well known. According to Hirsch (Geographical and Historical 
Pathology, I, p. 245) there died of malarial fevers per thousand of 
the population in Ceylon 
INCGBOES isos iy anda tae Daas I.I 
Natives of India................. 4-5 
Malay S 9.2 e ese aed ae ee ta abe 6.7 
Natives of Ceylon............... 7 
Europeans. ................0000. 24.6 
Indirectly, of course, lack of adequate nutrition is a frequent source of death 
as it predisposes people to die from various diseases. The same may be said of 
the indirect effects of climate. 
