The theory of spontaneous generation proposes that living organisms can arise from nonliving matter and was widely accepted for almost 2,000 years, until experiments by Francesco Redi and others challenged it. Which figure challenged it?

• A. Francesco Redi
• B. Aristotle
• C. Robert Hooke
• D. Antoni van Leeuwenhoek

Answer: (A)

The idea being tested is whether life can arise from nonliving matter. Francesco Redi addressed this by using careful, controlled experiments to separate the appearance of life from mere decay. He set up three containers with meat: one open to the air, one sealed shut, and one covered with a fine mesh that kept flies out while still allowing air to circulate. After a while, the open and mesh-covered jars developed maggots and flies, while the sealed jar did not. The consistent absence of maggots when flies couldn’t reach the meat shows that life arose from eggs laid by existing organisms (flies), not spontaneously from the meat itself. This directly challenges the notion of spontaneous generation and supports biogenesis—the idea that life comes from preexisting life. Aristotle had argued for spontaneous generation, so Redi’s experiments were a pivotal shift against that ancient view. Later work, like Pasteur’s broth and swan-neck flask experiments, strengthened the same conclusion. In this context, Redi is the figure who brought empirical evidence against spontaneous generation.