The globe skimmer dragonfly (Pantala flavescens) is the world’s longest distance flyer. It migrates 4,400 miles across the Indian Ocean without landing. It is the highest flying dragonfly too, found up at 6,200 meters in the Himalayas. That is quite amazing considering it’s just a 1 ½ inch insect.
Their increased wing surface area allows them to glide with extreme efficiency because they require less flapping which saves the dragonfly much energy. They catch a ride on high altitude weather currents following the rain. Moisture is necessary for them to breed. When they cross the Indian Ocean to Eastern Africa they are fleeing India’s dry season in favor of eastern Africa’s wet season.
Pantala need fresh water to mate and lay their eggs. If while gliding along their journey, riding a weather current, they come across a freshwater pool created by a rainstorm, they’ll dive earthward and use those pools to mate and lay eggs. In only a few weeks the eggs hatch and the baby dragonflies join the swarm’s intercontinental and now multi-generational trek right where their parents left off.
A research paper was written about them and published in the journal PLoS ONE. Biologists at Rutgers University-Newark (RU-N) who led the study said, “the evidence is in the genes. They found that populations of this dragonfly, called Pantala flavescens, in locations as far apart as Texas, eastern Canada, Japan, Korea, India, and South America, have genetic profiles so similar that there is only one likely explanation. Apparently – somehow – these insects are traveling distances that are extraordinarily long for their small size, breeding with each other, and creating a common worldwide gene pool that would be impossible if they did not intermingle.”
“This is the first time anyone has looked at genes to see how far these insects have traveled,” says Jessica Ware, an assistant professor of biology on the faculty of RU-N’s College of Arts and Sciences and senior author of the study. “If North American Pantala only bred with North American Pantala, and Japanese Pantala only bred with Japanese Pantala,” Ware says, “we would expect to see that in genetic results that differed from each other. Because we don’t see that, it suggests the mixing of genes across vast geographic expanses.”
It is interesting how Pantala (and its cousin the Green Darner – Anax junius) are the only world traveling dragonflies. The rest of their species barely even leave the pond from which they’re born!