Evolutionary Balancing Act Could Generate New Species
Once the Tufts team established that flashing had such a low energy cost, they tried a simple field experiment to measure the potential predation costs of firefly flash signals. Photinus fireflies are known to produce noxious chemicals that deter most predators, yet make them the top menu choice for the larger predatory fireflies known as Photuris. Using basic materials that included electronic fake fireflies (manufactured by Firefly Magic), plastic toy-dispensing capsules designed for vending machines, and sticky glue, the researchers made two startling discoveries.
In the field, predatory fireflies were attracted significantly more often to the fake firefly signals compared with non-flashing but otherwise identical controls. In addition, when flash signals were more frequent, they were much more likely to attract predators. So even though more conspicuous flash signals provide male fireflies with an evolutionary leg up in terms of attracting females, they also have a potentially fatal downside because they are more likely to attract predators in search of their next meal.
"Every single night, male fireflies are out there flying a fine line between sex and death. For us, it definitely rivals the most exciting television thriller!" says Lewis. "So, next time you're outside on a summer night take a moment to admire the firefly romance and risk thats playing out all around you."
According to Lewis, the importance of these two conflicting forces c
|Contact: Kim Thurler|