Billions of "Bourbon Brood" cicadas emerge in 12 states, marking a loud, 17-year cycle.

Billions of "Bourbon Brood" cicadas are emerging in Kentucky and parts of eleven other states this month after 17 years underground. Known as periodical cicadas, these insects embark on a noisy weeks-long mating ritual, with their high-pitched buzzing reaching up to 100 decibels. Despite being a nuisance due to their large numbers and decomposing remains, cicadas are harmless to humans. Scientists are studying how climate change might affect their emergence patterns and mating rituals.