Every year, in the month of June, tourists who visit the Great Smoky Mountains National Park in the United States are presented with an amazing sight. Like Christmas lights, fireflies are of sorts Photinus Carolinus shine in harmony. Only a few species of firefly, in North America and Southeast Asia, have this ability to glow all at once. By flapping, males seek to attract females, who also respond with blinks. Thus, without this synchronization, males and females would have difficulty finding each other in the bustle of the light. Since the beginning of XXe In the last century, scientists have wondered how these insects managed to emit their signals all at the same time, but for twenty years they have only tried to model the phenomenon through mathematical equations. Each type has its own characteristics. Madeline McCrea and her colleagues from the University of Pittsburgh in the US modeled the state of the species Photinus Carolinuswhose luminous behavior is particularly atypical.
The three scientists relied on data from observations in the wild and from experiments in a controlled environment. Notice that a model of neuroscience is called Elliptical bomber – used to describe the behavior of neurons – accurately reproduces the periods of bursts of flashes and pauses in these fireflies. “The name says it all: If you draw these periods, they look a lot like an ellipse,” says Jonathan Rubin, one of the study’s authors.
“This model is interesting because it reproduces many subtleties of the reality of this species, completely absent from previous models,” says Rafael Sarfati, from the University of Colorado, who has been studying this phenomenon in fireflies since 2019. P. carolinus Glow quickly 6 or 7 times, pause for 2-3 seconds and then resume this cycle. These streams were often left out in previous modeling, which focused only on transmission and pause periods.
The researchers identified four factors that influence firefly synchronization: number of individuals, distance, flight speed, and biological factors. By playing on these values, they found results consistent with trials for parameters such as the number and position of fireflies. The more insects, the more the ballet lights sync and sync. Likewise, the farther away the fireflies are from each other, the less well they synchronize, as if they can no longer see each other. The effect of speed, for its part, wasn’t as clear. Madeline McCrea and her colleagues note that the faster an insect flies, the more it helps others to synchronize: more fireflies on the ground see the same signal emanating from the fast-flying individual.
In Biological Factors, biologists have grouped intrinsic parameters that influence a firefly’s ability to synchronize, such as light perception. But this is not well known. “This last parameter remains too simple to describe what happens during decision-making in a firefly. Perhaps the reality is more complex,” says Raphael Sarfati. To learn more, the latter became interested in another type of firefly, Fotinus frontaliswhose flashes follow a different rhythm. Together with his colleague Orit Peleg, he has just published a set of experimental data. In particular, they noticed that within the same swarm, different groups flashed by following the same pattern, but changed in time.
Understanding the mechanisms of firefly synchronization is particularly useful for assessing the effect of light pollution on the behavior of these insects.
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