Charles Darwin faced numerous challenges in his studies of evolution, including skepticism and controversy over his theories. His groundbreaking work, "On the Origin of Species," met resistance from both scientific and religious communities, as it contradicted the long-held belief in creationism. Darwin also struggled with personal doubts about whether his conclusions would undermine the integrity of his faith. Additionally, the meticulous collection and analysis of data during his voyage on the HMS Beagle were time-consuming and arduous. Despite these challenges, Darwin's persistence resulted in a transformative understanding of natural selection that reshaped biological sciences.