It was Darwin's genius both to show how all this evidence favored the evolution of species from a common ancestor and to offer a plausible mechanism by which life might evolve.
Lamarck and others had promoted evolutionary theories, but in order to explain just how life changed, they depended on speculation.
As Darwin wrestled with natural selection he spent a great deal of time with pigeon breeders, learning their methods.
He found their work to be an analogy for evolution.
He found several species of finch adapted to different environmental niches.
The finches also differed in beak shape, food source, and how food was captured.He wanted to amass a wealth of evidence before publicly presenting his idea.During those years he corresponded briefly with Wallace (right), who was exploring the wildlife of South America and Asia.Animals, Adaptation, and the Galpagos Islands Collect the Clues Make the Match Unlock the Mystery Interview With Paleontologist Dr.A visit to the Galapagos Islands in 1835 helped Darwin formulate his ideas on natural selection.A pigeon breeder selected individual birds to reproduce in order to produce a neck ruffle.Similarly, nature unconsciously "selects" individuals better suited to surviving their local conditions.Wallace, on the other hand, continued his travels and focused his study on the importance of biogeography.The book was not only a best seller but also one of the most influential scientific books of all time.Typically, they claimed that evolution was guided by some long-term trend.Lamarck, for example, thought that life strove over time to rise from simple single-celled forms to complex ones.