Final answer:
Francesco Redi refuted the belief in spontaneous generation with experiments showing maggots on meat only appear when flies have access, laying eggs that develop into maggots.
Step-by-step explanation:
People historically believed in the concept of spontaneous generation, which held that living organisms could arise from nonliving matter. This was a widely accepted notion supported by thinkers like Aristotle, who claimed that creatures such as maggots formed spontaneously from decaying meat. In contrast, Francesco Redi made careful observations and conducted experiments that refuted spontaneous generation. In his experiments in 1668, Redi demonstrated that maggots only appeared on meat that was exposed to flies, proving that they were the offspring of flies, not spontaneously generated.
He placed meat in six containers: two open, two covered with gauze, and two sealed. Maggots developed only in the containers that were left open, whereas no maggots appeared in the gauze-covered or sealed containers. This provided evidence that spontaneous generation of maggots did not occur and that maggots were formed from fly eggs. Redi's work laid the foundation for later scientists like Louis Pasteur, who further disproved spontaneous generation and supported the principle that 'life only comes from life'.