Discrediting spontaneous generation,
Scandiano, Duchy of Modena and Reggio
Pavia, French First Republic
|Institutions||University of Modena and Reggio Emilia|
University of Pavia
University of Padua
Lazzaro Spallanzani (12 January 1729 11 February 1799) was an Italian Catholic priest (for which the name was coined for him: Abbe Spallanzani) biologist and physiologist who made significant contributions to the study of the bodily functions, reproduction in animals and echolocation in animals. Biogenesis research led the way to the demise in the concept of spontaneous generation an prevailing belief in the time when organisms are born from inanimate matter but the ultimate for the concept was delivered with the help of French scientists Louis Pasteur a century later.
The most significant of his works were summarized by his publication Experiencias Para Servir a La Historia de La Generacion De Animales y Plantas (Experiences to serve to the History of the Generation of Animals and Plants), published in 1786. Some of his contributions include experiments of fertilisation between spermatozoa and ova, and in vitro fertilization.
Spallanzani was born Scandiano in the present Province in Reggio Emilia to Gianniccolo Spallanzani and Lucia Zigliani. His father, who was a lawyer by trade was not impressed by the young Spallanzani who was more involved playing with small animals rather than studying. With the financial assistance of the Vallisnieri Foundation, his father admitted him at Jesuit Seminary. Jesuit Seminary at age 15. When he was invited to join the Order but he declined.
Then, influenced by his father and with the assistance of Monsignor Castelvetro the bishop of Reggio and the Bishop of Reggio, he enrolled in laws and law at the University of Bologna, which ended his studies shortly and began a new path in research. In Bologna, his famous kinswoman, Laura Bassi, was the professor of physics, and it was due to her influence that his desire to study science has been attributable.
Together with her, he studied maths and natural philosophy, and paid great attention to the languages, both ancient and modern, but he eventually stopped studying these subjects. It was his good friend, Antonio Vallisnieri Jr. for his dad to persuade him to stop law school and instead pursue a career in academia.
Career and Education
At an age of 25 just after his ordination, to become a professor of metaphysics, logic and Greek at the university of Reggio. He was promoted to professor in 1763. moved towards Modena, the University of Modena, where the professor continued to teach with great enthusiasm and accomplishment, but all his time was devoted to the study of natural sciences.
He also served as a priest in the Congregation Beata Vergine and S. Carlo He turned down numerous invitations to other Italian universities, and also in 1768, he was a professor at St Petersburg until 1768, after which he accepted the offer by Maria Theresa to the chair of natural history at the University of Pavia, which was then undergoing a restructuring. He was also appointed curator of the institution, and was greatly enhanced with the treasures of his numerous travels across the shores of the Mediterranean Sea. In the month of June 1768, Spallanzani was appointed to be a Fellow in the Royal Society and in 1775 was made a foreign fellow to the Royal Swedish Academy of Sciences.
In 1785, he was admitted to the University of Padua, but to keep his position, the sovereign doubled his pay and permitted him to take a to take a leave of absence for a trip to Turkey in which he stayed for nearly one year.
He also made numerous observations, some of which could be mentioned the copper mine located in Chalki as well as an iron mine located in Principi. The return to his home country was an undisputed success: in Vienna the city he was warmly welcomed from Joseph II and on reaching Pavia the city, he was greeted by acclamations at Pavia’s gates student body of the University.
The following year, his students were more than five hundred. While on a trip to the Balkans as well as to Constantinople the integrity of the administration of the museum put to be in doubt (he has been accused of taking of objects from the collection of the university to build his own collection of curiousities) as well as the writing of letters across Europe to smear Spallanzani’s name.
A court investigation swiftly removed his reputation to the delight of a few people who had been his adversaries. However, Spallanzani took revenge on his main accused, an angry coworker who had planted the fake specimen of the composite “species”. When his colleague made public the amazing specimen, Spallanzani revealed the joke, leading to widespread ridicule and embarrassment.
In 1796, Spallanzani accepted an offer to be a professorship of the National Museum of Natural History, France in Paris, but he declined the position because of his age. He died of bladder cancer on the 12th of February 1799 in Pavia. Following his death the bladder was removed to be studied by his coworkers, following which it was put on display in the museum of Pavia which is where it is until today.
His unstoppable efforts as a traveler as well as his talent and fortune as a collector his excellence as an educator and expositor, as well as his ability to be controversialist are the explanation for Spallanzani’s remarkable fame among his peers; his letters reveal his close relationship with a variety of famous philosophers and scholars such as Georges-Louis-Leclerc, Comte de Buffon Lavoisier along with Voltaire.
But there were other qualities that are not in doubt. His entire life was filled with constant and unending curiosity about the natural world from every angle and his numerous and diverse works are a testament to an original and fresh genius capable of presenting and resolving problems across every science field, while at the same while determining the real cause for the phenomenon of stones skipping (formerly thought to be caused by the water’s elasticity) as well as helping to establish the foundations of modern meteorology and volcanology.
Contributions of Lazzaro Spallanzani
Spallanzani’s initial scientific research was completed in 1765. Saggio of osservazioni microscopically relevant to the system of generation the signors of Needham and Buffon (Essay on the microscopic evidence about the system of generation used by Messrs. Needham and Buffon) that was the first comprehensive rebuttal on the concept of spontaneous generation.
In the 1765 time period, the microscope was in use by researchers. Using it, the advocates of the theory the French scientists Pierre Louis de Maupertuis Buffon as well as John Needham, came to the conclusion that there was an inherent life-generating force in some kinds of inorganic matter that allows living microbes to develop in the event of enough time.
Spallanzani’s research proved that this isn’t an intrinsic characteristic of matter and that it is destroyed in one hour of boiling. Because the microbes didn’t reappeared in the event that the material was sealed hermetically and sealed, he suggested that microbes circulate through air, and could be destroyed by boiling. Needham asserted that the experiments have destroyed that “vegetative force” that was necessary for spontaneous generation to take place. Spallanzani set the stage for research conducted by Louis Pasteur, who defeated the idea of spontaneous generation nearly century after.
In his research work Dissertationi of fisica animale as well as vegetablee (Dissertation regarding the biology of animals as well as vegetables, two volumes 1780) Spallanzani was first to explicate the digestion process in animals. In this work, he first explained the process of digestion which he later proved that it was not just a mechanical procedure of trituration, which is the process of crushing food particles and consuming it. It was a chemical solution that occurs predominantly in the stomach due to the action of gastric juice.
Spallanzani described animal (mammal) reproduction in his Experiencias Para Servir a La Historia de La Generacion De Animales y Plantas (1786). Spallanzani was the first to prove that fertilisation requires the spermatozoa as well as an ovum. Spallanzani was the first to conduct in vitro fertilization using frogs and artificial insemination with dogs. Spallanzani discovered that some species, particularly newts, are able to regenerate certain organs in the event of injury or removal surgically.
In spite of his science background, Spallanzani believed in preformationism, a belief that organisms grow out of their miniature selves; e.g. animals that are miniature animals or animalcules. He conducted a an experiment of filtration that was successful in separating seminal fluids of frogs, one liquid and the other an animalcule with gelatin (spermatozoa) part. However, he later believed that the liquid portion that was able to induce fertilisation. An ovist who was fervent, he believed that the animal form had already been developed in eggs, and that the semen’s fertilisation was just an activation of growth.
Spallanzani was also famous for the extensive research he conducted in 1793 about the ability of bats to fly in the night to find things (including predators) as well as avoid obstructions which led him to conclude that bats don’t make use of their eyes to navigate however, they use a different sense. He was initially inspired by his observations that a tamed barn owls flew perfectly at night in dim light candle, but crashed into the wall after the candle was snuffed out. He was able to catch three wild bats in Scandiono and carried out a similar experiments. On which the following was his note (on the 20th of 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 caught two bats and covered their eyes with a transparent discs made of birdlime. Then, to his surprise the bats flew normal. The surgeon further resorted to surgically taking the eyeballs off of one bat. He noticed 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.
He discovered that bats don’t require vision to navigate; however, he was unable to determine the reasons. The time was when other scientists were skeptical and ridiculed his findings. The Spallanzani’s contemporary The Swiss naturalist and doctor Louis Jurine, learned of Spallanzani’s work and studied the possibility of bat navigation. He observed that bats’ flight became disoriented after their ears were closed. However, Spallanzani believed that it was due to hearing because bats fly in silence. He repeated his experiment with improved ear plugs with turpentine, wax pomatum, or tinder, mixed with water to observe that bats that were blind were unable to navigate without hearing. However, he was still skeptical that deafness was the primary reason for the disorientation of flight, and believed that hearing was essential so he carried out some painful tests, such as burning and taking out the external ear, as well as piercing an inner ear. Following these procedures He was sure that hearing is the most important aspect to the normal flight of bats, on which he wrote:
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.
He was then convinced that he believed the auditory organ was a source of navigation, and wrote:
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?
The exact scientific concept was first discovered around 1938, by the two American biologists Donald Griffin and Robert Galambos.
Spallanzani researched the development and origins of marine fossils discovered in remote regions of the sea as well as over the ridges of certain regions of Europe and led to his 1755 publication of the short dissertationentitled “Dissertazione sopra i corpi marino-montani then presented at the meeting the Accademia degli Ipocondriaci di Reggio Emilia”. Although it was in accordance with one of the popular theories of the period, which believed that the presence of marine fossils on mountain tops to the natural movements of the sea, but not the flood that was universal, Spallanzani developed his own theory, basing it on the dynamic of the forces that altered the condition of the Earth in the time since God’s creation.
Then, a few years later Spallanzani wrote reports on excursions he took in Portovenere, Cerigo Island, and Two Sicilies, addressing important questions such as the discovery of fossilized shells in the volcanic rock, fossils of humans as well as the presence of fossils belonging to extinct species. The fossil issue is the way that, in the fashion of the 18th century, Spallanzani combined studies on his three nature kingdoms.
Spallanzani was a scientist who studied and wrote important observations regarding blood circulation and respiration. He was 1777 when he coined an epithet Tardigrada (from Latin meaning “slow-moving”) for the phylum of animals that includes one of the most robust extremophiles today.
In 1788, he travelled to Vesuvius as well as the volcanic craters of The Lipari Islands and Sicily, and documented the results of his investigations in a major work (Viaggi all due Sicilie ed in alcune parts of the Appennino) that was published four years afterward.