Butterflies and moths collect so much static electricity during their flight that pollen grains from flowers can be pulled across air gaps of a few millimeters or centimeters by static electricity.
The finding, published today in the Journal of the Royal Society Interface, suggests that this likely increases their efficiency and effectiveness as pollinators.
The University of Bristol team also noted that the amount of static electricity that butterflies and moths carry varies between different species, and that these variations correlate with differences in their ecology, such as whether they visit flowers, come from a tropical environment or flying in flight. the day or the night. This is the first evidence to suggest that the amount of static electricity an animal accumulates is a trait that can be adaptive, and thus evolution can act on it through natural selection.
Lead author Dr Sam England from the Bristol School of Biological Sciences explained: ‘We already knew that many animal species accumulate static electricity as they fly, most likely due to friction with the air. ability of flower-visiting animals, such as bees and hummingbirds, to pollinate by attracting pollen using electrostatic attraction.
“However, it was not known whether this idea applied to a broader range of equally important pollinators, such as butterflies and moths. So we set out to test this idea and see whether butterflies and moths also accumulate charge, and if so, whether this charge is sufficient is to attract pollen from flowers to their bodies.”
Their research involved 269 butterflies and moths, divided into 11 different species, originating from five different continents and in several different ecological niches. They could then compare them against each other and see if these ecological factors correlated with their charge, thereby determining whether static charge is a property that evolution can act on.
Dr. England added: “A clearer picture is developing of how the influence of static electricity on pollination could be very powerful and widespread.
“Establishing electrostatic charge as a property that evolution can act on raises a host of questions about how and why natural selection might lead animals to benefit or suffer from the amount of static electricity they accumulate.”
In terms of practical applications, this study opens the door to the possibility for technologies to artificially increase the electrostatic charges of pollinators or pollen, to improve pollination rates in natural and agricultural environments.
Dr. England concluded: “We have discovered that butterflies and moths accumulate so much static electricity as they fly that pollen is literally drawn to them through the air as they approach a flower.
“This means they don’t even have to touch flowers to pollinate them, making them very good at their job as pollinators and highlighting how important they can be to the functioning of our floral ecosystems.
“For me personally, I’d like to do a broader study of as many different species of animals as possible, see how much static electricity they accumulate, and then look at any correlations with their ecology and lifestyle. Then we can really start to understand how evolution and static electricity interact. interact!”
