Lazzaro Spallanzani was an Italian biologist and physiologist born in 1729. He is best known for his work in the fields of embryology and microbiology. Spallanzani conducted experiments that challenged the idea of spontaneous generation, demonstrating that microorganisms could be killed by boiling and that life did not arise from non-living matter. His research laid the groundwork for later scientists, including Louis Pasteur, who further explored the role of microorganisms in fermentation and disease. Spallanzani's contributions to the understanding of reproduction in animals and the development of the early embryo were also significant, influencing the study of developmental biology.