Born Jan. 12, 1729, in Scandiano; died Feb. 12, 1799, in Pavia. Italian naturalist.

Spallanzani graduated from the University of Bologna. He was a professor at universities in Reggio nell’Emilia (from 1755), Modena (from 1763), and Pavia (from 1769).

Spallanzani worked in various fields of natural science, but his studies in experimental biology are particularly well known. He was the first to demonstrate experimentally the impossibility of spontaneous generation of microscopic organisms (Infusoria). Using microscopy, he studied regeneration in amphibians; also, he was the first to carry out artificial fertilization in amphibians and mammals. He found that eggs do not begin to develop until they have made contact with sperm. However, as an ovist (an adherent of preformation), he assumed that seminal fluid rather than spermatozoa is the major factor in fertilization because it stimulates the growth of the organism, which apparently preexists in the egg. Spallanzani also studied blood circulation, respiration, digestion, and the sense organs.