Every autumn, motorists notice more deer bounding across roads and hikers hear aggressive clattering in the woods. Behind this surge in movement lies the annual deer rut—a complex biological event governed by diminishing daylight, surging hormones, and ancient reproductive rituals.

From silent flight and glowing night eyes to eerie screeches echoing through autumn woods, discover how the astonishing nocturnal adaptations of owls fueled centuries of folklore and made them the ultimate Halloween icon.

Every autumn, millions of Monarch butterflies embark on an epic 3,000-mile journey across North America to the high-altitude fir forests of central Mexico. Discover the astonishing genetics, internal compasses, and environmental triggers behind the insect kingdom’s greatest transcontinental migration.