Q. You once wrote that blue pigment is not known to exist in any terrestrial or freshwater animals with backbones. I found a blue bullfrog in a marsh in Virginia. It was mostly blue with some gray ...

Ptychadena nana individuals with green and brown color morphs. Image courtesy of Sandra Goutte. A team of researchers at NYU Abu Dhabi (NYUAD) has uncovered how a common color variation in frogs has ...