For many of us, one of the most common sights to see during a warm summer night is the soft glow given off by fireflies. But have you ever wondered what happens inside a firefly to make it glow?
HOW DO FIREFLIES GLOW?
For the last sixty years, scientists had a basic understanding of what makes a firefly light up – oxygen, calcium, magnesium, and luciferin (a naturally occurring chemical) react with each other producing light, referred to as bioluminescence. This chemical reaction produces a range of colors from yellow, green, orange, and even blue!
However, the details around the chemical reaction was a mystery until recently!
THE MISSING LINK OF HOW FIREFLIES GLOW
Scientists have been puzzled about two of the ingredients used to create the glow of the firefly: oxygen and luciferin. In general, these chemicals are not likely to react with each other to produce the bioluminescent glow like we see given off by the firefly.
It wasn’t until 2015 when scientist Bruce Branchini of Connecticut College and colleagues at Yale University successfully recreated the firefly’s glow in their lab where they discovered the missing link: superoxide anion!
SUPEROXIDE ANION? SAY WHAT?!
Simply put, a superoxide anion is a form oxygen that contains an extra electron. Because of this extra electron, the superoxide anion allows for luciferin to react with oxygen creating the bioluminescent glow emitted by the firefly!
WHAT CAN WE DO WITH LUCIFERIN
Stephen Miller, a chemical biologist at the University of Massachusetts Medical School who also studies luciferin and its potential uses for human health, underlined the importance of continuing to study luciferin (and bioluminescence in general) because of the potential applications for medicine, according to an article posted by National Geographic last year.
“For instance, earlier [in 2015], Miller was part of a team that used luciferin to detect specific enzymes in the brains of living rats, which could someday offer doctors another window into the human brain,” the National Geographic article went on to say.
While it’s important to note that rats are not humans, but it provides a solid foundation for scientists to continue studying luciferin and bioluminescence.