Oscar Hertwig (1849–1922)
Born 1849 CE, died 1922 CE.
Oscar Hertwig (21 April 1849 – 25 October 1922) was a German embryologist and zoologist known for his research in developmental biology and evolution. Hertwig is credited as the first person to observe sexual reproduction at the cellular level, by looking at the cells of sea urchins under the microscope.
Text from the Wikipedia article Oscar_Hertwig, licensed CC BY-SA 4.0.