Paul Jaccard, Date of Birth, Place of Birth, Date of Death

Paul Jaccard

Swiss botanist (1868-1944)

Date of Birth: 18-Nov-1868

Place of Birth: Sainte-Croix, Canton of Vaud, Switzerland

Date of Death: 09-May-1944

Profession: mathematician, university teacher, botanist

Nationality: Switzerland

Zodiac Sign: Scorpio

Paul Jaccard (18 November 1868 in Sainte-Croix – 9 May 1944 in Zurich) was a professor of botany and plant physiology at the ETH Zurich.
He studied at the University of Lausanne and ETH Zurich (PhD 1894).
He continued studies in Paris with Gaston Bonnier. He developed the Jaccard index of similarity (he called it coefficient de communauté) and published it in 1901. He also introduced the use of the species-to-genus ratio (he called it generic coefficient) in biogeography.
In the 1920s, Paul Jaccard engaged in a dispute with the Finnish botanist and phytogeographer Alvar Palmgren over the interpretation of species-to-genus ratio, as evidence of competitive exclusion (as held by Jaccard) or attributable to random sampling (as held by Palmgren).