has he written any book?
"The Voyage of the Beagle", "On the Origin of Species", "The Descent of Man","The Expression of the Emotions in Man and Animals", " The Power of Movement in Plants" and others.
Charles Darwin
 author of "The Voyage of the Beagle", as a geologist who had published extensively on South America and had solved the puzzle of the formation of coral atolls, and as a biologist who had published the definitive work on barnacles. While "On the Origin of Species" dominates perceptions of his work, "The Descent of Man" and "The Expression of the Emotions in Man and Animals" had considerable impact, and his books on plants including "The Power of Movement in Plants" were innovative studies of great importance, as was his final work on "The Formation of Vegetable Mould through the Action of Worms".
the process of natural selection principles and applications It is the differential survival and reproduction of individuals due to differences in phenotype. what does this selection refers to? A mechanism of evolution. what do you mean by this last term? It is change in the heritable characteristics of biological populations over successive generations. is there is any specific theory related to the previous selection process? Yes, Darwin's theory. what is stated in this theory? He defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved". who was this above person you previously mentioned? He was an English naturalist, geologist and biologist, best known for his contributions to the science of evolution.
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Charles Darwin [SEP] Works
Darwin was a prolific writer. Even without publication of his works on evolution, he would have had a considerable reputation as the author of "The Voyage of the Beagle", as a geologist who had published extensively on South America and had solved the puzzle of the formation of coral atolls, and as a biologist who had published the definitive work on barnacles. While "On the Origin of Species" dominates perceptions of his work, "The Descent of Man" and "The Expression of the Emotions in Man and Animals" had considerable impact, and his books on plants including "The Power of Movement in Plants" were innovative studies of great importance, as was his final work on "The Formation of Vegetable Mould through the Action of Worms".