Zhores Aleksandrovich Medvedev (; 14 November 1925 – 15 November 2018) was a Russian agronomist, biologist, historian and dissident. His twin brother is the historian Roy Medvedev. He was born in Tbilisi, Georgia. Medvedev published about 170 research papers and reviews, about sixty of them during his time in London. In 1973 he was one of the signers of the Humanist Manifesto.