Jan Swammerdam bigraphy, stories - Dutch entomologist

Jan Swammerdam : biography

12 February 1637 - 17 February 1680

Jan Swammerdam (February 12, 1637 – 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 1658, 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.

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.

Research on insects

Illustration of a Mosquito from Historia 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 is credited with the enhancement of the study of biology due to his work dissecting insects and studying them under microscopes.

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 different individuals"...whereas modern biologists speak of the grub, the pupa and the adult as stages in the life cycle of one individual butterfly, Harvey and his contemporaries always regarded the grub as one individual and the butterfly as another." page 30 or 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."Biblia natura, 1737, translated into English as The Book of Nature, 1758, by Swammerdam.

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 anatomical and 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.

Living octopus

Living octopus

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