Theodor Boveri

Theodor Heinrich Boveri (12 October 1862 – 15 October 1915) was a German biologist. He was notable for first hypothesising the cellular processes that cause cancer.
Boveri was married to the American biologist Marcella O'Grady (1863–1950). Their daughter Margret Boveri (1900–1975) became one of the best-known post-war German journalists.

Boveri's work with sea urchins showed that it was necessary to have all chromosomes present in order for proper embryonic development to take place. This discovery was an important part of the Boveri–Sutton chromosome theory. His other significant discovery was the centrosome (1888), which he described as the especial organ of cell division. Boveri also discovered the phenomenon of chromatin diminution during embryonic development of the nematode Parascaris.

He also reasoned in 1902 that a cancerous tumor begins with a single cell in which the makeup of its chromosomes becomes scrambled, causing the cells to divide uncontrollably. He proposed carcinogenesis was the result of aberrant mitoses and uncontrolled growth caused by radiation, physical or chemical insults or by microscopic pathogens. It was only later that researchers such as Thomas Hunt Morgan in 1915 demonstrated that Boveri was correct.