Jan Swammerdam

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There is no such thing as an authentic portrait of Swammerdam. What is shown here is based on a misinterpretation of a person in Rembrandt's "Anatomy of Dr Tulp".

Jan Swammerdam (born February 12, 1637 in Amsterdam ; † February 17, 1680 ibid) was a Dutch anatomist , biologist and naturalist and is considered the founder of the theory of preformations .

Life

Jan Swammerdam's father was a pharmacist in Amsterdam and was engaged in collecting coins, minerals and fossils. His mother died in 1661. In the year she died, Jan began studying medicine at the University of Leiden with Franciscus Sylvius . His fellow students were u. a. Reinier de Graaf , Frederik Ruysch and Niels Steensen . 1664 he went to Saumur and Paris , where he contacts with the wealthy polymath Tanneguy Le Fèvre and Melchisédech Thévenot tied, returned a year later back to Leiden and Amsterdam and was in 1667 with De respiratione , a treatise on breathing, to Dr. med. PhD. However, he only practiced his profession as a doctor to finance his passion, insect research. As a doctor, he often performed autopsies , and the findings were incorporated into his anatomical research. To this end, he also injected wax into blood vessels from anatomical specimens in order to illustrate them clearly.

From 1667 to 1675 he published three essays on the natural history of insects , which earned him a high reputation, but also aroused envy. Swammerdam led several lawsuits against former college friends, including quarreling with Graaf over who discovered the ovarian follicles first. At about the same time he fell ill with malaria . The outbreak of the Franco-Dutch War in 1672 also led to the economic ruin of the Swammerdam family.

Swammerdam had long been haunted by doubts that arose from contradictions in his research on the Bible. In 1675 he traveled to the Flemish mystic Antoinette Bourignon in Schleswig and for a time neglected his research in favor of spiritual knowledge. Even an invitation to Duke Cosimo III mediated by his college friend Niels Steensen . to Florence , who offered him 12,000 guilders to exhibit and complete his insect collection there, he turned down. However, he continued his research with the aim of discovering the divine plan of creation in small living beings. He died at the age of 43. The papers he left behind appeared only in 1737/38, translated into Latin by Hermann Boerhaave under the title Biblia naturae .

research

The model of a frog muscle from 1658, with which he refuted the millennia-old belief that muscles are made to contract by filling fluid via nerves, but did not believe his research himself.

Swammerdam was among the first researchers to use the microscope . He was in contact with his compatriots Antoni van Leeuwenhoek and Christiaan Huygens . As early as 1658 he was the first person to describe the (red) blood cells in frog serum that he discovered under the microscope .

Until the invention of the microscope, insects were considered too unimportant to be classified. A large part of his entomological work therefore consists of a system , with which he laid the basis for further researchers. Swammerdam's microscopic examinations of insects also showed that, contrary to what was previously assumed, insects did not produce spontaneously from mud or the like. emerged, but develop like all other animals. He recognized that the queen is the only female of the bee colony capable of reproduction and established that the metamorphosis of insects is nothing more than the development and growth of already existing systems.

Other important studies deal with the life cycle of frogs and the construction of the female reproductive organs of the people . Swammerdam was able to “prove” that all life comes from an egg ; the human egg in the form of the egg cell remained hidden from him as a discovery of the 19th century. With his research he also postulated the preformation theory , the doctrine of the predetermination of all forms of life, which replaced the epigenetic ideas that had been in effect since Aristotle , according to which the embryo gradually develops with its various parts from the initially unformed mass of both parents. While this ancient idea, which was also respected in the Middle Ages, was much closer to modern embryogenesis , Swammerdam's preformist position, which prevailed in the following two centuries, said that all future humans would already have been nested in the bud in the first egg, that of Eve . According to this, a woman's child would already be fully developed in her egg as a miniature ( homunculus ), while the man would only take on mechanical functions, so that Swammwerdam is one of the ovists of preformation theory.

Swammerdam is also considered to be the first to describe the phenomenon that muscles do not increase in volume when they contract, as Galen said . In doing so, however, he did not believe in appearance, but rather Descartes ' hypothesis of a “nerve alcohol” that flows from the brain via the nerves into the muscles and dilates them. The method he developed for isolating individual frog muscles was still used centuries later.

Works

  • Historia insectorum generalis. Utrecht 1669.
  • Miraculum naturae sive uteri muliebris fabrica, notis in D. Joh. Van Horne prodromum illustrata, & tabulis [...] adumbrata. Adjecta est nova methodus, cavitates corporis ita præparandi, ut suam semper genuinam faciem servent [...]. Leiden (with Severinus Matthaei) 1672. Digitized edition of the University and State Library Düsseldorf

Designations

literature

Web links

Individual evidence

  1. ↑ Swammerdam: Bible of Nature , plate 39  ( page no longer available , search in web archives )  Info: The link was automatically marked as defective. Please check the link according to the instructions and then remove this notice. (Object of the month December 2007 in the scientific collections of the Humboldt University Berlin).@1@ 2Template: Toter Link / www.sammlungen.hu-berlin.de  
  2. ^ Matthew Cobb: Swammerdam on muscles: right without realizing it .
personal data
SURNAME Swammerdam, Jan
BRIEF DESCRIPTION Dutch naturalist, founder of the theory of preformations
DATE OF BIRTH February 12, 1637
PLACE OF BIRTH Amsterdam
DATE OF DEATH February 17, 1680
Place of death Amsterdam