Edouard van Beneden

Son of zoologist Pierre-Joseph van Beneden, Édouard became professor of zoology and comparative anatomy at the University of Liège in 1870. Utilizing the intestinal roundworm of horses (Ascaris megalocephala) due to its minimal chromosome count, he conducted meticulous cytological microscopy.

In his 1883 monograph Recherches sur la maturation de l'oeuf, Van Beneden discovered that egg and sperm each contribute exactly half the chromosomes to the fertilized zygote (meiosis), establishing that chromosomes are the physical carriers of heredity. He also discovered the centrosome organelle.