The sun is setting in Princeton, New Jersey, and Joseph Yoon is plucking cicadas off the grave of Aaron Burr. Princeton Cemetery is the final resting place of the infamous politician who killed Alexander Hamilton. This May and June, it’s also been home to a group of Brood X cicadas. On this night, cicada nymphs crawl across 18th-century stone engravings, adults flutter from grave to grave, and empty, molted shells crunch underfoot. The cemetery is an apt location for the group: After living for 17 years underground as nymphs, Brood…