A southern leopard frog. - Credit: Photo from Montgomery County Department of Environmental Protection. This story was corrected at 12:25 p.m. on Feb. 4, 2014. An explanation follows the story.Can you ...

Months of old-fashioned scientific fieldwork - more than 2,000 surveys of chirping frog calls, hundreds of photos of individual frogs and tiny tissue samples taken from them - has helped define the ...