Lazzaro Spallanzani
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Lazzaro Spallanzani (January 10, 1729 - February 12, 1799) was an Italian biologist whose research of biogenesis paved the way for later discoveries by Louis Pasteur.
[edit] Biography
He was born in Scandiano, Reggio Emilia and died in Pavia, Italy. Spallanzani was educated at the Jesuit College and started to study law at the University of Bologna, which he gave up soon and turned to science. Here, his famous kinswoman, Laura Bassi, was professor of physics and it is to her influence that his scientific impulse has been usually attributed. With her he studied natural philosophy and mathematics, and gave also great attention to languages, both ancient and modern, but soon abandoned the study.
In 1754, at the age of 25 he became professor of logic, metaphysics and Greek in the University of Reggio, and in 1760 was transferred to Modena, where he continued to teach with great assiduity and success, but devoted his whole leisure to natural science. He declined many offers from other Italian universities and from St Petersburg until 1768, when he accepted the invitation of Maria Theresa to the chair of natural history in the university of Pavia, which was then being reorganized. He also became director of the museum, which he greatly enriched by the collections of his many journeys along the shores of the Mediterranean.
In 1785 he was invited to Padua, but to retain his services his sovereign doubled his salary and allowed him leave of absence for a visit to Turkey where he remained nearly a year and made many observations, among which may be noted those of a copper mine in Chalki and of an iron mine at Principi. His return home was almost a triumphal progress: at Vienna he was cordially received by Joseph II and on reaching Pavia he was met with acclamations outside the city gates by the students of the university.
During the following year his students exceeded five hundred. His integrity in the management of the museum was called in question, but a judicial investigation speedily cleared his honour to the satisfaction even of his accusers. In 1788 he visited Vesuvius and the volcanoes of the Lipari Islands and Sicily, and embodied the results of his researches in a large work (Viaggi alle due Sicilie ed in alcune parti dell'Appennino), published four years later. He died from bladder cancer on the 12th of February 1799, in Pavia.
His indefatigable exertions as a traveller, his skill and good fortune as a collector, his brilliance as a teacher and expositor, and his keenness as a controversialist no doubt aid largely in accounting for Spallanzani's exceptional fame among his contemporaries; yet greater qualities were by no means lacking. His life was one of incessant eager questioning of nature on all sides, and his many and varied works all bear the stamp of a fresh and original genius, capable of stating and solving problems in all departments of science -- at one time finding the true explanation of "ducks and drakes" (formerly attributed to the elasticity of water) and at another helping to lay the foundations of our modern vulcanology and meteorology.
Spallanzani researched the theory about the spontaneous generation of cellular life in 1768. His experiment proved that microbes come from the air and that they could be killed through boiling. This work paved the way for later research by Louis Pasteur.
Lazzaro also discovered and described animal (mammal) reproduction, showing that it requires both semen and an ovum. He was the first to perform an artificial insemination, using a dog. Spallanzani showed that some animals, especially lizards, can regenerate some parts of their body if injured or surgically removed. He is also famous for extensive experiments on the navigation in complete darkness by bats, where he concluded that they have sensory capacities that he could not explain. We now know bats navigate around obstacles and locate prey by using the echoes from emitted ultra sounds (echolocation).
His great work, however, is the Dissertationi de fisica animale e vegetale (2 vols, 1780). Here he first interpreted the process of digestion, which he proved to be no mere mechanical process of trituration - that is, of grinding up the food - but one of actual chemical solution, taking place primarily in the stomach, by the action of the gastric juice. He also carried out important researches on fertilization in animals (1780).
