On a sweltering summer day in 2010, a construction worker in the southeastern Chinese city of Ganzhou was digging the foundation for a building when his backhoe smashed into something hard. Climbing down to see what it was, he probably expected the worst—impenetrable bedrock, an old water main or some other nuisance that would inevitably delay completion of the sprawling industrial park his crew was racing to finish. But when the dirt and smoke cleared, a very different culprit came into focus: bones—lots of them, some enormous.