Sunday, March 8, 2020

Antonie van Leeuwenhoek, Father of Microbiology

Antonie van Leeuwenhoek, Father of Microbiology Anton van Leeuwenhoek (October 24, 1632–August 30, 1723) invented the first practical microscopes and used them to become the first person to see and describe bacteria, among other microscopic discoveries.  Indeed, van Leeuwenhoeks work effectively refuted the doctrine of spontaneous generation, the theory that living organisms could spontaneously emerge from nonliving matter. His studies also led to the development of the sciences of bacteriology and protozoology. Fast Facts: Anton van Leeuwenhoek Known For:  Improvements to the microscope, discovery of bacteria, discovery of sperm, descriptions of all manner of microscopic cell structures (plant and animal), yeasts, molds, and moreAlso Known As: Antonie Van Leeuwenhoek, Antony Van LeeuwenhoekBorn:  Oct. 24, 1632 in Delft, HollandDied:  Aug. 30, 1723 in in Delft, HollandEducation:  Only basic educationPublished Works:  Arcana naturÅ“ detecta, 1695, a collection of his letters sent to the Royal Society of London, translated into Latin for the scientific communityAwards:  Member of the Royal Society of LondonSpouse(s): Barbara de Mey (m.1654–1666),  Cornelia Swalmius (m. 1671–1694)Children: MariaNotable Quote:  My work...was not pursued in order to gain the praise I now enjoy, but chiefly from a craving after knowledge. Early Life   Leeuwenhoek was born in Holland on October 24, 1632, and as a teenager he became an apprentice at a linen drapers shop. Although it doesnt seem a likely start to a life of science, from here Leeuwenhoek was set on a path to inventing his microscope. At the shop,  magnifying glasses were used to count the threads and inspect the quality of cloth. He was inspired and taught himself new methods for grinding and polishing tiny lenses of great curvature, which gave magnifications up to 275x (275 times the subjects original size), the finest known at that time. Contemporaneous Microscopes People had been using magnifying lenses since the 12th century and convex and concave lenses for vision correction since the 1200s and 1300s. In 1590, Dutch lens grinders Hans and Zacharias Janssen constructed a microscope with two lenses in a tube; though it may not have been the first microscope, it was a very early model. Also credited with the invention of the microscope about the same time was Hans Lippershey, the inventor of the telescope. Their work led to others research and development on telescopes and the modern compound microscope, such as Galileo Galilei, Italian astronomer, physicist, and engineer whose invention was the first given the name microscope. The compound microscopes of Leeuwenhoeks time had issues with blurry figures and distortions and could magnify only up to 30 or 40 times. Leeuwenhoek Microscope Leeuwenhoeks work on his tiny lenses led to the building of his microscopes, considered the first practical ones. They bore little resemblance to todays microscopes, however; they were more like very high-powered magnifying glasses and used only one lens instead of two. Other scientists didnt adopt Leeuwenhoeks versions of microscopes because of the difficulty in learning to use them.  They were small (about 2 inches long) and were used by holding ones eye close to the tiny lens and looking at a sample suspended on a pin. Leeuwenhoek Discoveries With these microscopes, though, he made the microbiological discoveries for which he is famous. Leeuwenhoek was the first to see and describe bacteria (1674), yeast plants, the teeming life in a drop of water (such as algae), and the circulation of blood corpuscles in capillaries. The word bacteria didnt exist yet, so he called these microscopic living organisms animalcules. During his long life, he used his lenses to make pioneer studies on an extraordinary variety of things- living and nonliving- and reported his findings in more than 100 letters to the Royal Society of England and the French Academy. Leeuwenhoeks first report to the Royal Society in 1673 described bee mouthparts, a louse, and a fungus. He studied the structure of plant cells and crystals, and the structure of human cells such as blood, muscle, skin, teeth, and hair. He even scraped the plaque from between his teeth to observe the bacteria there, which, Leeuwenhoek discovered, died after drinking coffee. He was the first to describe sperm and postulated that conception occurred when a sperm joined with an ovum, though his thought was that the ovum just served to feed the sperm. At the time, there were various theories of how babies formed, so Leeuwenhoeks studies of sperm and ovum of various species caused an uproar in the scientific community. It would be around 200 years before scientists would agree on the process. Leeuwenhoeks View on His Work Like his contemporary  Robert Hooke, Leeuwenhoek made some of the most important discoveries of early microscopy. In one letter from 1716, he wrote, My work, which Ive done for a long time, was not pursued in order to gain the praise I now enjoy, but chiefly from a craving after knowledge, which I notice resides in me more than in most other men. And therewithal, whenever I found out anything remarkable, I have thought it my duty to put down my discovery on paper, so that all ingenious people might be informed thereof. He did not editorialize on meanings of his observations and acknowledged he was not a scientist but merely an observer. Leeuwenhoek was not an artist either, but he worked with one on the drawings he submitted in his letters. Death Van Leeuwenhoek also contributed to science in one other way. In the final year of his life, he described the disease that took his life. Van Leeuwenhoek suffered from uncontrollable contractions of the diaphram, a condition now known as Van Leeuwenhoek disease. He died of the disease, also called diaphragmatic flutter, on August 30, 1723, in Delft. He is buried at the Oude Kerk (Old Church) in Delft. Legacy Some of Leeuwenhoeks discoveries could be verified at the time by other scientists, but some discoveries could not because his lenses were so superior to others microscopes and equipment. Some people had to come to him to see his work in person. Just 11 of Leeuwenhoeks 500 microscopes exist today. His instruments were made of gold and silver, and most were sold by his family after he died in 1723. Other scientists did not use his microscopes, as they were difficult to learn to use. Some improvements to the device occurred in the 1730s, but big improvements that led to todays compound microscopes didnt happen until the middle of the 19th century. Sources â€Å"Antonie Van Leeuwenhoek.†Ã‚  Famous Biologists Antonie Van Leeuwenhoek Comments, famousbiologists.org.Cobb, M. An Amazing 10 Years: The Discovery of Egg and Sperm in the 17th Century. Reproduction in Domestic Animals 47 (Suppl. 4; 2012), 2–6, Faculty of Life Sciences, University of Manchester, Manchester, UK.Lane, Nick. The Unseen World: Reflections on Leeuwenhoek (1677) ‘Concerning Little Animals.’  Philosophical Transactions of the Royal Society of London Series B, Biological Sciences 370 (1666) (April 19, 2015): 20140344.Samardhi, Himabindu Radford, Dorothy M. Fong, Kwun. (2010). Leeuwenhoeks disease: Diaphragmatic flutter in a cardiac patient. Cardiology in the Young. Cardiology in the Young. 20. 334 - 336.Van Leeuwenhoek, Anton. Letter of June 12, 1716, to the Royal Society, quoted by the University of California Museum of Paleontology, Berkeley.Vision Engineering. Later Developments.