Antonie van Leeuwenhoek

c. 1632–1723 · Delft · Often called the “Father of Microbiology.”

Contribution

Built high-quality single-lens microscopes and was the first to observe and describe single-celled organisms (“animalcules”) — bacteria and protozoa — in letters to the Royal Society (1670s).

Why It Still Matters

Microbiology begins with seeing. Direct observation made microbes real objects of science and opened the path to germ theory centuries later.

Active Recall

  1. What did Leeuwenhoek call the organisms he saw?
  2. Why was better microscopy a prerequisite for medical microbiology?