If you’ve spent any time on the internet over the past few weeks, you’ve probably stumbled upon the glow-in-the-dark petunia that scientists genetically engineered to emit a continuous green glow.

Firefly petunias, genetically modified with bioluminescent mushroom DNA, glow in the dark. The glow, primarily from the flowers, is most vibrant in new blooms and is similar to moonlight.

As if this didn’t attract enough attention, we’ve now learned that they also glow in the dark. Biofluorescent organisms are everywhere, from mushrooms to fish to reptiles and amphibians ...