Question

In formulating the theory of evolution by natural selection, Charles Darwin was greatly influenced by:
A. environmental factors
B. mutations
C. Malthus idea on population control
D. all of these

Answer 1

Hint:-Natural selection is the process involving changes in the organism over time due to changes in their heritable physical or behavioral traits. These changes occur to adapt to the environmental conditions for survival and reproduction.

Complete step-by-step solution:-
The theory of evolution by natural selection was first formulated in the book “Origin of Species” in 1859 by Charles Darwin. The following points were included in this theory:
In each generation, more individuals are produced that are able to survive.
Among individuals, phenotypic variations exist which are known to be heritable.
The individuals that possess heritable traits that suit better to the environment will survive.
New species were formed because of reproductive isolation.
Charles Darwin was greatly influenced by the idea of Malthus on population control. This idea which is known as Malthusianism states that the growth of population is exponential while the growth of food and other resources is linear. This idea was brought up from the economic and political thoughts of Thomas Robert Malthus which was laid out in his writings, An Essay on the Principle of Population in the year 1798. This idea greatly inspired Darwin to formulate the theory of evolution by natural selection.

Malthusian theory of population growth.
Options (A) and (B) are incorrect because environmental factors and mutations were the key points in the theory of evolution by natural selection. These points did not inspire Darwin to formulate this theory but they were the key points in this theory.
Hence, option (D) is also incorrect because option (A) and (B) are already incorrect.
So, the correct option is (C).

Note:- Charles Darwin was greatly influenced by the Malthus idea on population. The main theme in his idea was that the population will always overpower the food and other resources which will lead to states of hunger, disease, and struggle. Thus, the natural struggle for survival caught Darwin’s attention and he extended the idea of Malthus in his theory of evolution by natural selection.