Jan Swammerdam (February 12, 1637, Amsterdam - February 17, 1680) was a
Dutch biologist and microscopist. His work on insects
demonstrated that the various phases during the life of an insect—egg, larva, pupa, and adult—are different forms of the same animal. As part of his
anatomical research, he carried out experiments on muscle contraction. In 1668, he
was the first to observe and describe red blood cells. He was one of the first people to
use the microscope in dissections, and his techniques remained useful for hundreds of
years.
Biography
Swammerdam was born in Amsterdam. His father was an apothecary, and an amateur collector
of minerals, coins, fossils, and insects from around the world. His mother died in 1661. The same year, when he was 24, Swammerdam entered the
University of Leiden to study medicine. After qualifying as a candidate in medicine in
1663, he left for France, spending time in Saumur and Paris. He returned to Leiden in September 1665, and earned his M.D. on February 22, 1667.
Once he left university, he spent much of his time pursuing his interest in insects. This choice caused a rift between
Swammerdam and his father, who thought his son should practice medicine. The relationship between the two deteriorated;
Swammerdam's father cut off his financial support for Swammerdam's entomological studies. As a result, Swammerdam was forced, at
least occasionally, to practice medicine in order to finance his own research.
From 1667 through 1674, Swammerdam continued his research and published three books. In 1675, he came under the influence of
the Flemish mystic, Antonia Bourignon, renounced his
work, and decided to devote the remainder of his life to spiritual matters. There is evidence, however, that he did not
completely give up his scientific studies. The papers, which he wished to be published posthumously, appear to have been revised
during the last two years of his life. He died at age 43 of malaria. In 1737-1738, a half century after his death,
Herman Boerhaave translated Swammerdam's papers into Latin and published them under the
title Biblia naturae (Book of Nature).
Research on Insects
Knowledge of insects in the 17th century was to a great extent inherited from Aristotle.
According to this classical paradigm, insects were so insignificant they weren't worthy of the types of investigations done on
fish, reptiles, and mammals. Much
of Swammerdam's entomological work was done to show that the difference between insects and the "higher" animals was one of
degree, not kind.
Swammerdam's principal interest in this area was demonstrating that insects develop in the same gradual manner as other
animals. He wanted to dispel the seventeenth-century notion of metamorphosis--the idea that different life stages of an insect (e.g. caterpillar and butterfly) represent a sudden change from
one type of animal to another. He garnered evidence against this claim from his dissections. By examining larvae, he identified
underdeveloped adult features in pre-adult animals. For example, he noticed that the wings of dragonflies and mayflies exist prior to their final molt. Swammerdam used these observations to bolster his case for epigenesis in his 1669 publication, Historia Insectorum Generalis (The Natural History of insects).
This work also included many descriptions of insect anatomy. It was here that Swammerdam revealed that the "king" bee has
ovaries. Biblia natura published posthumously in 1737, carried the first confirmation that
the queen bee is the sole mother of the colony. Despite five intense years of beekeeping, the
mode of honey bee reproduction escaped him as he wrote, "I do not believe the male bees actually copulate with the
females."[1]
Illustration of a Mosquito from
Historia
In addition to his research on metamorphosis, Swammerdam's entomological work stands out because he was among the first people
to study insects in a systematized fashion (i.e., careful dissection, comparison of different species, and use of the
microscope). His anat behavioral descriptions of bees, wasps,
ants, dragonflies, snails,
worms, and butterflies were major contributions to the nascent
field of entomology in the late seventeenth
century.
Besides Historia, he published Miraculum naturae sive uteri muliebris fabrica in 1672 and Ephemeri vita,
in 1674. The latter was a study of the mayfly, written at a time when he was becoming increasingly involved in spiritual matters.
The work contains long passages on the glory of the creator. His Bybel der Natuure was a
collection of his papers and drawings.
Research on Anatomy
Swammerdam was not a pioneer in the study of anatomy, as he was in study of insects, but he nonetheless made important
contributions. He played a significant role in debunking the balloonist theory, which
held that muscles contract because of an influx of air or fluid. His two best-known experiments in this field were both conducted
on frogs. In the first, after he removed the heart of a frog, he observed that touching certain
areas of the brain caused certain muscles to contract. For Swammerdam, this was evidence that the brain, not the circulatory system, was responsible for muscle contractions. In the
second experiment, Swammerdam placed severed frog muscle under water and caused it to contract. He noted that the water level did
not rise and therefore concluded no air or fluid could be flowing into the leg. His use of, and experiments with, frog muscle
preparations played a key role in the development of our current understanding of nerve-muscle function. He also discovered valves in the lymphatic system, which
were later dubbed Swammerdam valves.
Contributions to Methodology
Though Swammerdam's work on insects and anatomy was
significant, many current histories remember him as much for his methods and skill with microscopes as for his discoveries. He
developed new techniques for examining, preserving, and dissecting specimens, including wax injection to make viewing blood
vessels easier.
Spirituality
Swammerdam's scientific work was deeply influenced by his religious views. For him, studying the Earth's creatures revealed
the greatness of God; scientific pursuits were pious activities. His spiritual views not only motivated his work, but also
affected his ideas about the natural world. For example, he rejected metamorphosis and spontaneous generation because
they represented randomness and haphazardness that was not possible in a world regulated by God.
His ultimate departure from the scientific scene in 1675 can also be attributed to his religiosity. Perhaps due to the
influence of Antoinette Bourignon, Swammerdam came to believe that his scientific
work was no longer in the service of God. He thought he was conducting investigations into the natural world merely to satisfy
his own curiosity. As a result, he subjected himself to the tutelage of Bourignon and, for the most part, renounced scientific
study.
External links
- [1]--Site devoted to Swammerdam.
- [2]--Short biography
from a website that chronicles the "rocky road to modern paleontology and biology."
- [3]--Biography written by Matthew Cobb, a professor at Laboratoire d'Ecologie in Paris.
- [4]-- Swammerdam insect plates from the University of Copenhagen Library
Bibliography
- Cobb M. 2002. Exorcizing the animal
spirits: John Swammerdam on nerve function. Nature Reviews, Volume 3, Pages 395-400.
- This article incorporates text from the Encyclopædia
Britannica Eleventh Edition, a publication now in the public
domain.
- Winsor, Mary P. "Swammerdam, Jan." Dictionary of Scientific
Biography. 1976
- Cobb, Matthew. "Reading and writing The Book of Nature: Jan Swammerdam (1637-1680)." Endeavour. Vol. 24(3).
2000.
- O'Connell, Sanjida. "A silk road to biology." The Times. May 27, 2002.
- Hall, Rupert A. From Galileo to Newton 1630-1720R. &R. Clark, Ltd., Edinburgh: 1963.
Further reading
- Jorink, Eric. "'Outside God there is Nothing': Swammerdam, Spinoza, and the Janus-Face of the Early Dutch Enlightenment."
The Early Enlightenment in the Dutch Republic, 1650-1750: Selected Papers of a Conference, Held at the Herzog August
Bibliothek Wolfenbuttel, 22-23 March 2001. Ed. Wiep Van Bunge. Leiden, The Netherlands: Brill Academic Publishers, 2003.
81-108.
- Fearing, Franklin. "Jan Swammerdam: A Study in the History of Comparative and Physiological Psychology of the 17th Century."
The American Journal of Psychology 41.3 (1929): 442-455
- Ruestow, Edward G. The Microscope in the Dutch Republic: The Shaping of Discovery. New York: Cambridge University
Press, 1996.
- Ruestow, Edward G. "Piety and the defense of natural order: Swammerdam on generation." Religion Science and Worldview:
Essays in Honor of Richard S. Westfall. Eds. Margaret Osler and Paul Lawrence Farber. New York: Cambridge University Press,
1985. 217-241.
References and notes
- ^ Biblia natura, 1737, translated to English as The Book of
Nature, 1758, by Swammerdam.
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