Final answer:
Neo-Malthusians advocate for population control through birth control and celibacy to prevent environmental degradation, resource conflicts, and potential Malthusian disasters like famine, disease, and war.
Step-by-step explanation:
Members of the neo-Malthusian movement advocated for measures to control population growth to prevent environmental degradation and potential resource-based conflicts. Influenced by Thomas Malthus's theory that populations grow geometrically and can outstrip the arithmetic growth of food supply, neo-Malthusians expanded the concern to the broader environment. Notably, a neo-Malthusian researcher named Paul Ehrlich in the 20th century emphasized the crucial role of the environment in sustaining population health and proposed a goal of zero population growth (ZPG). Neo-Malthusians support preventive checks like birth control and celibacy, arguing that without such measures, the increasing human population may lead to wars over scarce resources and environmental collapse.