can you name some places he visited during this travel?
St Jago in Cape Verde, Brazil and other places.
Charles Darwin
On their first stop ashore at St Jago in Cape Verde, Darwin found that a white band high in the volcanic rock cliffs included seashells. FitzRoy had given him the first volume of Charles Lyell's "Principles of Geology", which set out uniformitarian concepts of land slowly rising or falling over immense periods, and Darwin saw things Lyell's way, theorising and thinking of writing a book on geology. When they reached Brazil, Darwin 
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. 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. what does this first book deals with? It is a vivid travel memoir as well as a detailed scientific field journal covering biology, geology, and anthropology.
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Charles Darwin [SEP] Survey voyage on HMS "Beagle"
Despite suffering badly from seasickness, Darwin wrote copious notes while on board the ship. Most of his zoology notes are about marine invertebrates, starting with plankton collected in a calm spell. On their first stop ashore at St Jago in Cape Verde, Darwin found that a white band high in the volcanic rock cliffs included seashells. FitzRoy had given him the first volume of Charles Lyell's "Principles of Geology", which set out uniformitarian concepts of land slowly rising or falling over immense periods, and Darwin saw things Lyell's way, theorising and thinking of writing a book on geology. When they reached Brazil, Darwin was delighted by the tropical forest, but detested the sight of slavery, and disputed this issue with Fitzroy.