A video circulating on X shows Tesla's FSD (Supervised) system braking for an animal the driver hadn't yet noticed, the latest in a string of documented incidents where the system's perception outpaced human reaction time. Tesla's official account shared a video in July 2026 showing FSD detecting a deer in direct sunlight and initiating braking before the driver intervened. Earlier documented cases include a Cybertruck braking for four deer on a pitch-dark road and a separate highway-speed deer avoidance in Calgary, Canada. Deer-vehicle collisions cause roughly 1.5 million accidents annually in the US alone, with most occurring at dusk and dawn. FSD v14.3, released in April 2026, included a reported 20% faster reaction time alongside enhanced detection of smaller animals. According to release notes and community tracking, FSD v14.3.11 and v14.3.13 — both released in October 2026 — further refined hazard and animal detection, with documented examples of the system identifying small animals at night and executing smooth, natural-feeling slowdowns rather than hard emergency stops. Tesla CEO Elon Musk publicly identified the core remaining challenge in early October 2026: small dark animals on dark pavement at night, framing the solution as a software challenge rather than a hardware one.