"Weismann's Follies" refers to a series of experiments conducted by the German biologist August Weismann in the late 19th century. Weismann aimed to demonstrate that acquired characteristics are not inherited, challenging the prevailing ideas of Lamarckism. He famously cut the tails off mice for several generations, observing that their offspring still had tails, supporting the idea that genetic information is passed down through germ cells, not somatic changes. These experiments contributed to the development of modern genetics by emphasizing the distinction between germ cells and somatic cells. Weismann's work laid the groundwork for the understanding of inheritance, influencing later scientists like Gregor Mendel and shaping the field of evolutionary biology.