Early theory about sperm

Year: 1677 - 1820

After Antoni van Leeuwenhoek discovered the sperm cell in 1677, researchers in the following centuries engaged in intensive discussion about how humans could emerge from them. One of the most popular theory - the so-called preformationists - believed that sperm cells contained a small, pre-formed human body. The mother was merely an incubating chamber.

The belief persisted until the early 19th century. By then, new developments in microbiology like improved microscopes and better preparation techniques led to the field of embryology, and it slowly became apparent that organisms are the product of both male and female reproduction cells.

The century-long commitment to the importance of the sperm cell shows how sexual bias can slip into scientific reasoning. When lacking evidence leaves room for speculation, implicit bias can easily lead to failure.

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