Question

Regarding Charles Darwin and Alfred Wallace Journeys, How did studying different organisms lead the two men to the same discovery? Who had the simpler path? The more difficult?

Answer 1

Charles Darwin had explained the theory of evolution by natural selection in his publication The Origin of Species in 1859. He would not have completed his book without another British Scientist, Alfred Wallace. Wallace had discussed the term transmutation and also the geographical barriers.

In theory of natural selection, Darwin stated about:

1) Variation among individuals of the species

2) Competition among the same species due to the presence of limited resources i.e. struggle for their existence

3) Survival of the fittest, the fit individual would survive and others would lead to death.

4) Individuals with favorable variations would survive and reproduce at much higher rates.

5) Adaptation, the variation which increases the chances of survival would be inherited to the next generations in a particular environment.

Darwin had explained the natural selection with the example of the Giraffe, that shorter necked Giraffes were eliminated and those were with longer neck were favored, selected and later adapted to the environment.

At that time, Alfred Wallace was also traveling through the different areas from amazon of Africa to the Malay Archipelago for his field study. He is also known as the father of Biogeography. He observed that the Asian subspecies which is present in the westernmost island of Malay Archipelago were absent in the eastern islands. In the eastern island, he found some other species of Australian origin. He concluded that the two closely related species might have inhabited by the same territory but during evolution, they got separated by the large biogeographical barriers. He observed that the geographical isolation has let the species to differentiate and forming new species.

Wallace had shared his essays and work with Darwin, One of them was "On the Law which has Regulated the Introduction of New Species". Darwin realized that they both were thinking of the same theory of natural selection, adaptation, and speciation. Wallace was one of the defenders of Darwin's theory.  As he independently also come up with the theory of natural selection.

Saying simpler and difficult part would not justify their study, but if we talk about the fact of time involved in the study and all the statement of the natural selection. Darwin work was much more seemed to be difficult and appreciated because for making the theory of natural selection publicly unveil, it took him more than 20 years to gather all the shreds of evidence and compile all the aspects of the natural selection i.e. variation, competition, survival of the fittest, reproduction and adaptation.

Wallace had also given the same theory but he didn't work on all the aspects, his work was more focused on the species differentiation and adaptation based on the geographical barriers.