August Friedrich Leopold Weismann was a prominent biologist and evolutionary theorist who lived during the late 19th century. Over the course of his life, he worked tirelessly to understand the mechanisms underlying inheritance and evolution, and his insights helped shape the modern understanding of genetics and evolutionary biology. Among his many accomplishments, Weismann is perhaps best known for his work on the germ plasm theory, which argues that hereditary information is stored primarily in germ cells rather than in somatic cells. This groundbreaking idea has since become a cornerstone of modern genetics, and Weismann is widely regarded as one of the most influential biologists of his time.