Editing Jan Swammerdam (section)

== ''Bybel der natuure'' ==
[[File:Swammerdam, Jan – Bybel der Natuure, 1693 – BEIC 11959684.jpg|thumb|''Bybel der Natuure'', 1693]]
His religious crisis only interrupted his scientific research briefly and until his premature death aged 43, he worked on what was to become his main work. It remained unpublished when he died in 1680 and was published as ''Bybel der natuure'' posthumously in 1737 by the Leiden University professor [[Herman Boerhaave]].<ref>Swammerdam, Jan. 1737-1758. ''[https://www.biodiversitylibrary.org/item/209892#page/1165/mode/1up Bybel der natuure] {{Webarchive|url=https://web.archive.org/web/20201209230238/https://www.biodiversitylibrary.org/item/209892#page/1165/mode/1up |date=2020-12-09 }}''. Amsteldammer. Of Historie der insecten</ref><ref>{{Cite book|title=The History of Science in the Netherlands: Survey, Themes and Reference|author1=Klaas Van Berkel |author2=Albert Van Helden |author3=L. C. Palm |publisher=BRILL|year=1999|isbn=9789004100060|pages=63}}</ref> Convinced that all insects were worth studying, Swammerdam had compiled an epic treatise on as many insects as he could, using the microscope and dissection. Inspired by [[Marcello Malpighi]], in  ''De Bombyce'' Swammerdam described the anatomy of [[silkworms]], [[mayflies]], [[ants]], [[stag beetle]]s, [[cheese mite]]s, [[bees]] and many other insects. His scientific observations were infused by his [[Religion in Europe|belief in God]], the almighty creator.<ref>{{Cite book|title=Early Modern Zoology: The Construction of Animals in Science, Literature and the Visual Arts|author1=Karl A. E. Enenkel |author2=Mark S. Smith |publisher=BRILL|year=2007|isbn=9789047422365|pages=163}}</ref> Swammerdam's praise of the [[louse]] went on to become a classic:

<blockquote>Herewith I offer you the Omnipotent Finger of God in the anatomy of a louse: wherein you will find miracle heaped on miracle and see the wisdom of God clearly manifested in a minute point.<ref name="ReferenceB"/> </blockquote>

===Research on bees===
[[File:Reproductive organs of the bee. Wellcome L0000176.jpg|thumb|right|Swammerdam's drawing of the queen bee's reproductive organs, as observed through the microscope.]]

Since ancient times it had been asserted that the queen bee was male, and ruled the hive. In 1586 [[Luis Mendez de Torres]] had first published the finding that the hive was ruled by a female, but Torres had maintained that she produced all other bees in the colony through a "seed". In 1609 [[Charles Butler (beekeeper)|Charles Butler]] had recorded the sex of drones as male, but he wrongly believed that they mated with worker bees. In ''Biblia naturae'' the first visual proof was published that his contemporaries had mistakenly identified the [[queen bee]] as male.<ref>{{Cite book|title=The Dancing Bees: Karl Von Frisch and the Discovery of the Honeybee Language|author = [[Tania Munz]] |publisher=University of Chicago Press|year=2016|isbn=9780226020860|pages=164}}</ref> Swammerdam also provided evidence that the queen bee is the sole mother of the colony.<ref name="Eva Crane 1999 569">{{Cite book|title=The World History of Beekeeping and Honey Hunting|author = Eva Crane |publisher=Taylor & Francis|year=1999|isbn=9780415924672|pages=569}}</ref> 

Swammerdam had engaged in five intense years of [[beekeeping]]. He had found that [[drone (bee)|drones]] were masculine, and had no [[stinger]]. Swammerdam identified the worker bees as "natural [[eunuchs]]" because he was unable to detect [[ovaries]] in them, but described them as nearer to the nature of the female. Swammerdam had produced a drawing of the queen bee's reproductive organs, as observed through the microscope.<ref>{{Cite book|title=The Dancing Bees: Karl Von Frisch and the Discovery of the Honeybee Language|author = [[Tania Munz]] |publisher=University of Chicago Press|year=2016|isbn=9780226020860|pages=169}}</ref> The drawing Swammerdam produced of the internal anatomy of the queen bee was only published in 1737.<ref name="Eva Crane 1999 569"/> His drawing of the [[honeycomb]] geometry was first published in ''Biblia naturae'', but had been referenced by [[Giacomo Filippo Maraldi]] in his 1712 book.<ref>{{Cite book|title=The World History of Beekeeping and Honey Hunting|author = Eva Crane |publisher=Taylor & Francis|year=1999|isbn=9780415924672|pages=564}}</ref> Details of Swammerdam's research on bees had already been published elsewhere because he had shared his findings with other scientists in correspondence. Among others, Swammerdam's research had been referenced by [[Nicolas Malebranche]] in 1688.<ref name="ReferenceC"/>

===Research on muscles===
[[Image:Swammerdam frog thigh.PNG|thumb|right|Swammerdam's illustration of a nerve-muscle preparation. He placed a frog thigh muscle in a glass syringe with a nerve protruding from a hole in the side of the container. Irritating the nerve caused the muscle to contract, but the level of the water, and thus the volume of the muscle, did not increase.]]
In ''Biblia naturae'' Swammerdam's research on muscles was published. Swammerdam played a key role in the debunking of the [[balloonist theory]], the idea that 'moving spirits' are responsible for muscle contractions.  The idea, supported by the Greek physician [[Galen]], held that nerves were hollow and the movement of spirits through them propelled muscle motion.<ref name="Cobb">
{{cite journal |author=Cobb M |title=Timeline: Exorcizing the animal spirits: Jan Swammerdam on nerve function |journal=Nature Reviews Neuroscience |volume=3 |issue=5 |pages=395–400 |year=2002 |pmid=11988778 |doi=10.1038/nrn806 |s2cid=5259824 |url=http://www.janswammerdam.net/NRN.pdf |url-status=dead |archive-url=https://web.archive.org/web/20050515053936/http://janswammerdam.net/NRN.pdf |archive-date=2005-05-15 }}</ref> [[René Descartes]] furthered the idea by basing it on a model of [[hydraulics]], suggesting that the spirits were analogous to fluids or gasses and calling them 'animal spirits'.<ref name="Cobb"/> In the model, which Descartes used to explain [[reflex]]es, the spirits would flow from the [[brain ventricle|ventricles of the brain]], through the nerves, and to the muscles to animate the latter.<ref name="Cobb"/> According to this hypothesis, muscles would grow larger when they contract because of the animal spirits flowing into them.  To test this idea, Swammerdam placed severed frog thigh muscle in an airtight syringe with a small amount of water in the tip.<ref name="Cobb"/> He could thus determine whether there was a change in the volume of the muscle when it contracted by observing a change in the level of the water (image at right).<ref name="Cobb"/> When Swammerdam caused the muscle to contract by irritating the nerve, the water level did not rise but rather was lowered by a minute amount; this showed that no air or fluid could be flowing into the muscle.<ref name="Cobb"/> The idea that nerve stimulation led to the movement had important implications for [[neuroscience]] by putting forward the idea that behavior is based on stimuli.<ref name="Cobb"/>

Swammerdam's research had been referenced before its publication by [[Nicolas Steno]], who had visited Swammerdam in Amsterdam. Swammerdam's research concluded after Steno had published the second edition of ''Elements of Myology'' in 1669, which is referenced in ''Biblia naturae''.<ref>{{Cite book|title=Steno on Muscles|author=Troels Kardel|publisher=American Philosophical Society|year=1994|isbn=9780871698414|pages=[https://archive.org/details/stenoonmusclesin0000unse/page/16 16]|url=https://archive.org/details/stenoonmusclesin0000unse/page/16}}</ref> A letter from Steno to Malpighi from 1675 suggests that Swammerdam's findings on muscle contraction had caused his crisis of consciousness. Steno sent Malpighi the drawings Swammerdam had done of the experiments, saying "when he had written a treatise on this matter he destroyed it and he has only preserved these figures. He is seeking God, but not yet in the Church of God."<ref>{{Cite book|title=Steno on Muscles|author=Troels Kardel|publisher=American Philosophical Society|year=1994|isbn=9780871698414|pages=[https://archive.org/details/stenoonmusclesin0000unse/page/17 17]|url=https://archive.org/details/stenoonmusclesin0000unse/page/17}}</ref>