Carbon Dating

Carbon dating is radiometric dating tuned for living things. The atmosphere constantly makes a trace of radioactive carbon-14, and every organism takes it in while alive, so its tissue matches the air. At death, intake stops and the carbon-14 decays with a half-life of 5,730 years — so the fraction left is a clock reading the time since death.^[1] After roughly 50,000 years too little remains to measure, which is why radiocarbon is perfect for archaeology and recent remains but useless for dinosaurs — those need the long-lived isotopes of ordinary radiometric dating.^[2]