Lysenkoism is a political and scientific movement in the Soviet Union, named after the agronomist Trofim Lysenko. It rejected the principles of Mendelian genetics and natural selection, promoting the idea that environmental factors could directly alter an organism's traits, which could then be inherited. This theory was aligned with Marxist ideology, emphasizing the role of the environment in shaping life. Lysenko's ideas gained favor in the 1930s and 1940s, leading to the suppression of genetic research and the persecution of scientists who opposed him. The movement had significant negative impacts on Soviet agriculture and biology, resulting in crop failures and a decline in scientific progress.