Fireflies fill the air for their annual mating season in the Great Smoky Mountains National Park's Elkmont Campground outside Gatlinburg, Tenn. on Tuesday, June 3, 2014. Males flash in flight, hoping ... more 
Fireflies fill the air for their annual mating season in the Great Smoky Mountains National Park's Elkmont Campground outside Gatlinburg, Tenn. on Tuesday, June 3, 2014. Males flash in flight, hoping to attract stationary females below. This photograph was made by 'stacking' 204 long exposures shot over a 1.5 hour period, recording fireflies' light trails in their outdoor disco. (AP Photo/Knoxville News Sentinel, Adam Lau) less 
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Associated Press | Photo By Knoxville News Sentinel, Adam Lau
Fri, Jun 6, 2014 2:24 AM EDT