A historical & scientific archive

The discovery timeline

Seven eras of microbiology, from the first microscope to synthetic biology. Every entry links to a scientist, discovery, or species already documented in this archive.

Microscopic era 1670s - 1850s

1676

Antonie van Leeuwenhoek observes animalcules through a hand-ground lens in Delft, the first documented sighting of microbial life.

1683 - 1700

Leeuwenhoek continues cataloguing microscopic life, including protozoa such as Giardia and Volvox globator.

Microbiology emerges 1840s - 1870s

1847

Ignaz Semmelweis shows hand-washing with chlorinated lime sharply reduces childbed fever in Vienna, before germ theory existed to explain it.

1854

Filippo Pacini first describes the comma-shaped bacterium found in cholera victims.

1861

Louis Pasteur's swan-neck flask experiments disprove spontaneous generation.

1867

Joseph Lister applies germ theory to surgery, introducing carbolic acid antisepsis.

1873

Gerhard Armauer Hansen identifies the leprosy bacillus, the first bacterium ever linked to a human disease.

Golden age of microbiology 1876 - 1910

1876

Robert Koch proves Bacillus anthracis causes anthrax, the first bacterium ever proven to cause a specific disease.

1880 - 1884

Koch's postulates are formulated; Staphylococcus aureus, Streptococcus pneumoniae, and Mycobacterium tuberculosis are identified.

1884

Hans Christian Gram develops the differential staining method still used to classify bacteria today.

1892 - 1898

Ivanovsky and Beijerinck discover viruses as agents distinct from bacteria, using the tobacco mosaic disease.

1894

Alexandre Yersin isolates the plague bacillus in Hong Kong during the Third Plague Pandemic.

1905

Schaudinn and Hoffmann identify the spirochete that causes syphilis.

Antibiotic era 1917 - 1950s

1917

Felix d'Herelle discovers bacteriophages, coining the term after identifying viruses that kill bacteria.

1928

Alexander Fleming discovers penicillin after mold contamination kills bacteria on a culture plate.

1943

Selman Waksman and Albert Schatz isolate streptomycin, the first effective tuberculosis treatment.

Molecular era 1928 - 1970s

1928

Frederick Griffith discovers bacterial transformation, hinting at a transferable genetic substance.

1944

Avery, MacLeod, and McCarty show DNA, not protein, carries genetic information.

1946 - 1952

Lederberg, Tatum, Zinder, Hershey, and Chase reveal conjugation, transduction, and confirm DNA as the genetic material.

1953

Watson, Crick, and Franklin reveal the double-helix structure of DNA.

1970

Restriction enzymes are discovered, enabling recombinant DNA technology.

1977

Carl Woese's rRNA sequencing reveals Archaea as a domain of life distinct from Bacteria.

Genomic era 1983 - 2000s

1983

Kary Mullis conceives PCR; Barre-Sinoussi and Montagnier isolate HIV.

1995 - 1996

The first bacterial genome (Haemophilus influenzae) and first archaeal genome (Methanocaldococcus jannaschii) are fully sequenced.

2007

The Human Microbiome Project launches, mapping microbial communities across the human body.

Modern microbiology 2012 - present

2012

Doudna and Charpentier adapt bacterial CRISPR into a programmable gene-editing tool.

2020

SARS-CoV-2 is identified and sequenced within weeks of the first reported cases in Wuhan.