Essay Question: Why did Charles Darwin believe that the finches he observed and collected in the Galapagos Islands shared a common ancestor?

English naturalist, Charles Darwin, believed the finches he collected and observed on the Galapagos Islands shared a common ancestor because he found they all greatly resembled a bird located on the Ecuadorian coast off South America. When Darwin initially began his journey on the Beagle, he was biased toward the widely accepted idea that every living thing on Earth was a divine creation, which remained unchanging and existing as it was originally created. However, when …

…due to frequent use or disuse, and was eventually passed through to their offspring. For example he proposed the lengthing of the giraffe's neck was due in part to the trees it lived among. In order for it to obtain its food it had to crane its neck forward and reach up. Lamarck, believe, over time, the giraffes structure eventually began to get longer and longer as it was passed from each genernertaion of offspring.