While bees do most of the pollination hype, butterflies and moths are some of our planet’s most important pollinators. During flight, they collect so much static electricity that pollen grains are pulled up from flowers without the insects even touching the plants. The pollen can travel in air gaps of a few millimeters or centimeters in this way, and using static electricity in this way also potentially increases their efficiency and effectiveness as pollinators. The findings are described in a study published July 23 in the Journal of the Royal Society Interface.
The team from the University of Bristol in the United Kingdom also noted that the amount of static electricity transferred by moths and butterflies varies depending on the species. These fluctuations are related to differences in their ecology, including whether or not they come from a tropical habitat, visit flowers, or whether they are day or night flyers. According to the teamthis is the first evidence to suggest that the amount of static electricity an animal accumulates is an adaptive trait and that evolution can act on it through natural selection.
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“We already knew that about many animal species[s] accumulate static electricity as they fly, most likely due to friction with the air,” study co-author and University of Bristol biologist Sam England said in a statement. “There were also suggestions that this static electricity could improve the ability of flower-visiting animals, such as bees and hummingbirds, to pollinate, by attracting pollen using electrostatic attraction.”
What wasn’t known was whether this static trick applied to a wider range of equally important pollinators, namely moths and butterflies. The research was intended to test this and see whether the insects also accumulate charge and whether the charge is sufficient to attract the pollen from the flowers to their bodies.
In the studythe team examined 269 butterflies and moths from 11 different species. The insects originally came from five different continents and lived in different ecological niches. This helped the researchers compare different environments to see if and which ecological factors correlated with the amount of charge present in the species, to see if static charge is a trait that evolution can act on. They discovered that the influence of static electricity on pollination may in fact be very powerful and widespread throughout the animal kingdom.
“Establishing electrostatic charge as a property that evolution can act on raises a host of questions about how and why natural selection might cause animals to benefit or suffer from the amount of static electricity they accumulate,” England said. .
In the future, this type of research could pave the way for technologists to artificially increase electrostatic charges as a way to improve pollination rates in both agricultural and natural environments.
“We discovered that butterflies and moths accumulate so much static electricity as they fly that pollen is literally pulled toward them through the air as they approach a flower,” England said. “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.”
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In future studies, the team wants to study more species to see how much static electricity they accumulate compared to moths and butterflies, and to see if there are any correlations with their lifestyle and ecology.
“Then we can really understand how evolution and static electricity interact!” said England.