Lazzaro Spallanzani
Lazzaro Spallanzani | |
---|---|
Scientific career | |
Fields | Biology |
Institutions | University of Modena and Reggio Emilia University of Pavia University of Padua |
Lazzaro Spallanzani (Italian pronunciation:
His most important works were summed up in his book Experiencias Para Servir a La Historia de La Generación De Animales y Plantas (Experiences to Serve to the History of the Generation of Animals and Plants), published in 1786. Among his contributions were experimental demonstrations of fertilisation between ova and spermatozoa, and in vitro fertilisation.
Biography
Spallanzani was born in
In 1754, at the age of 25, soon after he was ordained he became professor of
In 1785 he was invited to University of 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. While he was travelling in the Balkans and to Constantinople, his integrity in the management of the museum was called in question (he was accused of the theft of specimens from the university's collection to add to his own cabinet of curiosities), with letters written across Europe to damage Spallanzani's reputation. A judicial investigation speedily cleared his honour to the satisfaction of some of his accusers.[6] But Spallanzani got his revenge on his principal accuser, Giovanni Antonio Scopoli, by preparing a fake specimen of a new "species". When Scopoli published the remarkable specimen, Spallanzani revealed the joke, resulting in wide ridicule and humiliation.[7][8]
In 1796, Spallanzani received an offer for professor at the National Museum of Natural History, France in Paris, but declined due to his age. He died from bladder cancer on 12 February 1799, in Pavia. After his death, his bladder was removed for study by his colleagues, after which it was placed on public display in a museum in Pavia, where it remains to this day.
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; his letters account for his close relationships with many famed scholars and philosophers, like
Scientific contributions
Spontaneous generation
Spallanzani's first scientific work was in 1765 Saggio di osservazioni microscopiche concernenti il sistema della generazione de' signori di Needham, e Buffon (Essay on microscopic observations regarding the generation system of Messrs. Needham and Buffon) which was the first systematic rebuttal of the theory of the
Louis Pasteur, who defeated the theory of spontaneous generation almost a century later.[10]
Digestion
In his work Dissertationi di fisica animale e vegetale (Dissertation on the physiology of animals and vegetables, in 2 volumes, 1780), Spallanzani was the first to explain the process of digestion in animals. Here he first interpreted the process of
Reproduction
Spallanzani described animal (
In spite of his scientific background, Spallanzani endorsed
Echolocation
Spallanzani is also famous for extensive experiments in 1793 on how bats could fly at night to detect objects (including prey) and avoid obstacles, where he concluded that bats do not use their eyes for navigation, but some other sense.[13][14] He was originally inspired by his observation that tamed barn owl flew properly at night under a dim-lit candle, but struck against the wall when the candle was put out. He managed to capture three wild bats in Scandiano, and performed a similar experiment, on which he wrote (on 20 August 1793):
Having seen this, the candle was taken away, and for my eyes like for those of my brother and cousins we were in complete darkness. Yet the animals continued to fly around as before and never struck against obstacles, nor did they fall down, as would have happened with a night-bird. Thus a place which we believe to be completely dark is not at all so, because bats certainly could not see without light.
A few days later he took two bats and covered their eyes with an opaque disc made of birdlime. To his astonishment, both bats flew completely normally. He went further by surgically removing the eyeballs of one bat, which he observed as:
[The bat] flew quickly, following the different subterranean pathways from one end to the other with the speed and sureness of an uninjured bat. More than once the animal landed on the walls and at the roof of the sotterranei and finally it landed in a hole in the ceiling two inches wide, hiding itself there immediately. My astonishment at this bat which absolutely could see although deprived of its eyes is inexpressible.[15]
He concluded that bats do not need vision for navigation; although he failed to find the reason. At the time other scientists were sceptical and ridiculed his findings. He was still suspicious that deafness alone was the cause of disoriented flight and that hearing was vital that he conducted some rather painful experiments such as burning and removing the external ear, and piercing through the inner ear. After these operations, he became convinced that hearing was fundamental to normal bat flight, upon which he noted:
This experiment, which is so decisively in favor of hearing ... has been repeated by me with equal results both in blinded bats and in seeing one.[15]
By then he was too convinced that he suggested the ear was an organ of navigation, writing:
The experiments of M. Professor Jurine, confirming by many examples those which I have done, and varied in many ways, establish without doubt the influence of the ear in the flight of blinded bats. Can it then still be said that ... [for bats] their ears rather than their eyes serve to direct them in flight?[17]
His pupil, Paolo Spadoni (1764-1826), also published observations on the topic.[18]
The exact scientific principle was discovered only in 1938 by two American biologists Donald Griffin and Robert Galambos.[19][20]
Fossils
Spallanzani studied the formation and origin of marine fossils found in distant regions of the sea and over the ridge mountains in some regions of Europe, which resulted in the publication in 1755 of a small dissertation, "Dissertazione sopra i corpi marino-montani then presented at the meeting the Accademia degli Ipocondriaci di Reggio Emilia". Although aligned to one of the trends of his time, which attributed the occurrence of marine fossils on mountains to the natural movement of the sea, not the universal flood, Spallanzani developed his own hypothesis, based on the dynamics of the forces that changed the state of the Earth after God's creation.[21]
A few years later, Spallanzani published reports about trips he made to
Other works
Spallanzani studied and made important descriptions on blood circulation and respiration.
In 1788 he visited
Much of his collections, which he kept at the end of his life in his house in Scandiano, were purchased by the city of Reggio Emilia in 1799. They are now on display inside the Palazzo dei Musei in two rooms denominated the Museo Spallanzani.
Publications
- Saggio di osservazioni microscopiche concernenti il sistema della generazione de' signori di Needham e Buffon (in Italian). Modena: eredi Bartolomeo Soliani (2.). 1765.
- Nuove ricerche sulle scoperte microscopiche (in French). Paris: Jacques Lacombe. 1769.
- Opuscoli di fisica animale e vegetabile (in Italian). Vol. 1. Modena: Società tipografica. 1776.
- Opuscoli di fisica animale e vegetabile (in Italian). Vol. 2. Modena: Società tipografica. 1776.
- Dissertazioni di fisica animale e vegetabile (in Italian). Vol. 1. Venezia: Giammaria Bassaglia. 1782.
- Dissertazioni di fisica animale e vegetabile (in Italian). Vol. 2. Venezia: Giammaria Bassaglia. 1782.
- Expériences pour servir a l'histoire de la génération des animaux et des plantes (in French). Genève: Barthelemi Chirol. 1785.
- Viaggi alle Due Sicilie e in alcune parti dell'Appennino (in Italian). Vol. 1. Pavia: Baldassare Comino. 1792.
- Viaggi alle Due Sicilie e in alcune parti dell'Appennino (in Italian). Vol. 2. Pavia: Baldassare Comino. 1792.
- Viaggi alle Due Sicilie e in alcune parti dell'Appennino (in Italian). Vol. 3. Pavia: Baldassare Comino. 1793.
- Viaggi alle Due Sicilie e in alcune parti dell'Appennino (in Italian). Vol. 4. Pavia: Baldassare Comino. 1793.
- Viaggi alle Due Sicilie e in alcune parti dell'Appennino (in Italian). Vol. 5. Pavia: Baldassare Comino. 1795.
- Lettere sopra il sospetto di un nuovo senso nei pipistrelli (in Italian). Torino: Stamperia reale. 1794.
- Chimico esame degli esperimenti del sig. Gottling (in Italian). Modena: Società tipografica. 1796.
- Memorie su la respirazione (in Italian). Vol. 1. Milano: Annesio Nobili. 1803.
- Memorie su la respirazione (in Italian). Vol. 2. Milano: Annesio Nobili. 1803.
Honours
Spallanzani was elected Fellow of the
See also
- List of Roman Catholic scientist-clerics
- Charles Jurine
References
- ^ Annals of Medical History. P.B. Hoeber. 1924. p. 177.
- PMID 10943424.
- ^ S2CID 84101575.
- ^ a b Walsh, James Joseph (1912). . In Herbermann, Charles (ed.). Catholic Encyclopedia. Vol. 14. New York: Robert Appleton Company.
- ^ "Spallanzani – Uomo e scienziato" (in Italian). Il museo di Lazzaro Spallanzani. Archived from the original on 3 June 2010. Retrieved 7 June 2010.
- ^ a b c d public domain: Chisholm, Hugh, ed. (1911). "Spallanzani, Lazaro". Encyclopædia Britannica. Vol. 25 (11th ed.). Cambridge University Press. pp. 592–593. One or more of the preceding sentences incorporates text from a publication now in the
- ^ Gigli Berzolari, Alberto (2000). Alessandro Volta and the Scientific Culture between 1750 and 1850. Milan: Istituto lombardo di scienze e lettere. p. 300.
- ^ Nosengo, Nicola (2005). "Rivalry and Revenge". Nature. 434 (142). Retrieved 10 February 2024.
- S2CID 27830790.
- ISBN 9780766143524.
- ^ ProQuest 871355494.
- S2CID 37213444.
- ^ Spallanzani concluded that in order to hunt at night, bats didn't rely on their eyes, but on some other sense; however, due to the experimental methods and the species of bat that he used, he didn't conclude that that other sense was hearing. See:
- Spallanzani, Lazzaro, Lettere sopra il sospetto di un nuovo senso nei pipistrelli (Letters on the suspicion of a new sense in bats), (Torino (Turin), (Italy): Stamperia Reale (Royal Press), 1794). [in Italian]
- ^ S2CID 11923119.
- ^ Peschier (1798) "Extraits des expériences de Jurine sur les chauve-souris qu'on a privé de la vue" (Extracts of Jurine's experiments on bats that have been deprived of sight), Journal de physique, de chimie, d'histoire naturelle … , 46 : 145–148. [in French]
- English translation: de Jurine, M. (July 1798). "VI. Experiments on bats deprived of sight". The Philosophical Magazine. 1 (2): 136–140. .
From these experiments the author concludes: … that the organ of hearing appears to supply that of sight in the discovery of bodies, and to furnish these animals with different sensations to direct their flight, and enable them to avoid those obstacles which may present themselves.
- English translation: de Jurine, M. (July 1798). "VI. Experiments on bats deprived of sight". The Philosophical Magazine. 1 (2): 136–140. .
- ^ S2CID 143497517.
- ^ Dissertazione epistolare sul volo di pippistrelli acieccati e sul passagio de'veggente
- .
- PMID 17776129.
- ^ SPALLANZANI, Lazzaro. Regno lapideo. In: Spallanzani, Lazzaro. Edizione nazionale delle opere di Lazzaro Spallanzani. Parte seconda: Lezione. Ed., Pericle di Pietro. Modena: Mucchi. v.1, pp. 233–318. 1788–1789 (1994)
- PMID 22281956.
- ISBN 9780123748553.
- ^ Fox-Skelly, Jasmin. "Tardigrades return from the dead". www.bbc.com. Retrieved 16 August 2021.
Bibliography
General
- . Microbe Hunters. Blue Ribbon Books. New York: Harcourt Brace & Company Inc. pp. 25–56. Retrieved 14 October 2020.
- Nordenskiöld, E. P. 1935 [Spallanzani, L.] Hist. of Biol. 247–248
- Rostand, J. 1997, Lazzaro Spallanzani e le origini della biologia sperimentale, Torino, Einaudi.
- Prestes, Maria Elice Brzezinski; Faria, Frederico Felipe de Almeida (December 2011). "Lazzaro Spallanzani e os fósseis: das observações em viagens naturalísticas ao ensino de história natural" [Lazzaro Spallanzani and fossils: from a naturalist's travel observations to the teaching of natural history]. História, Ciências, Saúde-Manguinhos (in Portuguese). 18 (4): 1005–1020. PMID 22281956.
Work on insects
- Conci, Cesare; Poggi, Roberto (1996). "Iconography of Italian Entomologists, with essential biographical data". Memorie della Società entomologica italiana. 75: 159–382. OCLC 889566579.
- Gibelli, V. 1971 L. Spallanzani. Pavia.
- Lhoste, J. 1987 Les entomologistes français. 1750–1950. INRA(Institut National de la Recherche Agronomique), Paris.
- Osborn, H. 1946 Fragments of Entomological History Including Some Personal Recollections of Men and Events. Columbus, Ohio, Published by the Author.
- Osborn, H. 1952 A Brief History of Entomology Including Time of Demosthenes and Aristotle to Modern Times with over Five Hundred Portraits.Columbus, Ohio, The Spahr & Glenn Company.
External links
- Page describing, with pictures, some of Lazzaro Spallanzani's memories
- Museum of Lazzaro Spallanzani in Pavia
- Official site of "Centro Studi Lazzaro Spallanzani" (Scandiano)
- Zoologica Göttingen State and University Library Digitised Viaggi alle due Sicilie e in alcune parti dell'Appennino
- Guide to the Lazzaro Spallanzani Papers 1768-1793 at the University of Chicago Special Collections Research Center