In 1968, Dr John B Calhoun, a behavioural researcher at the US National Institute of Mental Health (NIMH), began a groundbreaking study that may hold chilling warnings for humanity's future. Nicknamed Universe 25, officially titled the "Mortality-Inhibiting Environment for Mice", the experiment placed mice in a sealed, predator-free habitat measuring 4.6 feet (1.37 m) per side, stocked with unlimited food, water, nesting material, and climate control. The enclosure featured 256 nest boxes linked by mesh tunnels, creating a supposed rodent paradise, but what unfolded hinted at the potential path to human extinction. Universe 25 began with just eight healthy albino mice, four male and four female. After about 3 and half months, the first offspring were born. Thereafter, the mice population doubled every 55 days. By around month 19, the population peaked at approximately 2,200 mice. Despite the environment being capable of supporting up to 3,800-4,000 mice, reproduction ...