Concept explainers
To analyze:
The reason why Darwin wrote the note to himself, “Never use the word higher or lower”.
Introduction:
Darwinism is a theory of biological evolution developed by the English naturalist Charles Darwin. Darwin emphasizes the process of adaptation and the relationship between populations of organisms and the environments in which they lived.

Explanation of Solution
Darwin wrote a note to himself in the margin of a book that proposed a theory of cosmic and biological evolution: “Never use the word higher or lower”. Throughout his writing, for the many species he described, Darwin emphasized the process of adaptation and the relationship between populations of organisms and the environment in which they lived. The degree of complexity of an organism is not related to how well that organism is adapted to its environment. There is a tendency to judge animals that are more like humans as “higher organisms”, but animals perfectly adapted to their environment, though they may not be like humans, are not “lower organisms”. One species was never better or worse than another.
One species was never better or worse than another. Rather, each species was differentiated from the others with specializations that adapted individuals of that species to the particular niche in which they lived.
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