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14 Fun Facts About Dragonflies, From Their Lethal Hunting Prowess to Incredible Migratory Feats

a dragonfly perched on purple flowers

More than 3,000 known dragonfly species exist. I am happy taking photographs via Getty Images

There’s something magical about dragonflies. Whether it’s their many-lensed eyes, their captivating flight or their dramatic emergence into a majestic adult form, the insects have grabbed humans’ attention for centuries.

Here are 14 dragonfly facts that may surprise you.

1. Dragonfly ancestors of record-breaking proportions flew in prehistoric times.

Dragonfly-like creatures were some of the first winged insects to evolve, appearing on the scene roughly 300 million years ago. Modern dragonflies have wingspans of up to only about five inches, but an early relative of dragonflies in the fossil record—called Meganeuropsis permiana—has been found with a wingspan longer than two feet.

Some scientists theorize that high oxygen levels during the Paleozoic era allowed these dragonfly ancestors to grow to monster sizes.

2. Dragonflies are stunningly diverse.

There are more than 3,000 known species of dragonflies, all of which belong to the order Odonata, which means “toothed one” in Greek. Technically, however, dragonflies don’t have teeth—the name refers to the insect’s serrated mandible, which comes in handy for holding and crushing prey.

Damselflies are fellow members of Odonata, though they’re distinct from dragonflies, which have thicker bodies and bigger eyes. A handy way to tell them apart is to look at their wings at rest—dragonflies sit with their wings splayed flat, while resting damselflies close their wings together.

3. For the majority of their lives, most dragonflies are aquatic.

Before growing into their familiar, flying form, baby dragonflies live in the water. In their larval stage, the aquatic dragonflies eat just about anything—tadpoles, mosquitoes, fish, other insect larvae and even each other. This phase typically lasts one to three years—some species, however, are aquatic for just weeks or months, while others might remain as larvae for half a decade.

At the end of its larval stage, a dragonfly crawls out of the water; then, its exoskeleton cracks open and releases its abdomen, which had been packed in like a telescope. Its four wings come out, and the body dries and hardens over the next several hours.

From Nymph to Wings: The Dragonfly Life Cycle | Asia's Weirdest | National Geographic Wild UK

From there, most dragonflies live fast, so to speak—their adult life span is typically only one to three weeks, though some make it more than two months.

4. Dragonflies are expert fliers.

They can fly straight up and down, move forward and backward, hover like a helicopter and even mate in midair. Dragonflies rank among the world’s fastest flying insects, capable of reaching roughly 35 miles per hour.

Their aerial prowess is a crucial survival skill. If a dragonfly can’t fly, it will starve, because the insects only eat prey they catch while flying. But they’re resilient: “A dragonfly can be missing an entire wing and still capture prey,” Stacey Combes, now a researcher at the University of California, Davis, told the New York Times’ Natalie Angier in 2013.

a dragonfly in flight, approaching the camera

A migrant hawker (Aeshna mixta) in flight in Denmark Universal Images Group via Getty Images

5. Dragonflies are precise, lethal hunters.

Dragonflies catch their insect prey by grabbing it with their feet or mandibles. They’re so efficient in their hunting that, in a 2013 study, dragonflies captured approximately 95 percent of the prey released into their enclosure.

That’s “wildly high compared to where most predators are,” as Rachel Crane, a biologist at the University of California, Davis, said in a statement last year. For comparison, certain birds of prey—like owls, falcons and hawks—catch prey only about 25 percent of the time.

6. Dragonflies serve as a great control on the mosquito population.

A single adult dragonfly can eat around 30 to upwards of 100 mosquitoes per day—but according to the National Park Service, “the true number is likely closer to the lower end of that scale.” Regardless, the insects are such prevalent mosquito predators that they’ve earned the nickname “mosquito hawk.” Even in their larval stage, dragonflies feast on mosquitoes—a nymph might eat about 40 mosquito larvae daily.

7. They’re a muse for innovators.

The secret to the dragonfly's backwards flight

The flight of the dragonfly is so special that it has inspired engineers who dream of making robots that fly like dragonflies—even backward. In a 2018 study, researchers captured dragonfly flight with high-speed cameras, revealing that the insects angle their bodies vertically, at a 90-degree angle to the horizon, to achieve backward flight. They’re capable of independently moving and twisting each of their four wings to improve flight control. Engineers could use this knowledge to design more aerodynamic aerial robots.

8. Dragonfly mating is an acrobatic feat.

When dragonflies mate, the pair forms a flying, loop-like structure known as a mating wheel or mating circle—“though some hopeless romantics call it a heart,” as ecologist Jeff Mitton wrote in 2015. To initiate mating, the male will grasp the female’s neck with claspers on his abdomen. Sometimes, he will continue to guard the female from other males until she lays eggs in the water.

If a female doesn’t consent to mating, she might play dead. Or, she might wrestle away her suitor—by twisting, shaking, flying backward or clinging to a reed to thwart a takeoff, wrote Joshua Rapp Learn for Science in 2021. In certain cases, the female might even take control of the flight, then dunk the male into a body of water, buying herself time to flee.

9. A dragonfly has a nearly 360-degree field of view.

a close-up image of a dragonfly's eyes

Dragonflies have two large, compound eyes and three simple eyes called ocelli, each with a single lens. Sheikh Nafis via Pexels

With their enormous eyes, dragonflies have incredible panoramic vision that encompasses almost every angle, except for right behind them. Dragonflies actually have five eyes—two compound eyes, each with a whopping 28,000 lenses in some species, and three simple eyes called ocelli, which have one light-detecting lens each.

Compared to the human perspective—which is based on three types of light-sensing cells called opsins that are sensitive to red, green and blue—a dragonfly’s view of the world is powered by 11 to 30 opsins. This supercharged vision allows them to see ultraviolet colors and polarized light, according to the National Park Service.

10. Dragonflies congregate in mysterious swarms.

Hundreds of dragonflies of different species will gather in swarms, either for feeding or migration. Little is known about this often short-lived behavior, but the Dragonfly Swarm Project is collecting reports on swarms to better understand the behavior. (Report a swarm here to contribute to citizen science.)

In July, millions of dragonflies swarmed a Rhode Island beach, potentially looking for better habitat. While some called it an “apocalypse,” the sighting left others in awe.

11. The smallest dragonfly in the world is the scarlet dwarf.

a small, red dragonfly grips onto a plant

The scarlet dwarf is native to Southeast Asia, China and Japan. © budak via iNaturalist under CC BY-NC 4.0

The planet’s smallest known dragonfly is less than two centimeters long. Known as the scarlet dwarf, the littlest specimen is just 0.59 inches long (15 millimeters), and the species has a wingspan of about 0.79 inches (20 millimeters). The dragonflies are native to Southeast Asia, as well as China and Japan.

12. Habitat degradation has put dragonflies at risk.

In a 2021 assessment, the International Union for Conservation of Nature found that 16 percent of 6,016 studied species of dragonflies and damselflies are at risk of extinction as they lose the freshwater breeding grounds needed to maintain their populations. Clearing of forests in South and Southeast Asia as well as in Central and South America has driven habitat loss for the insects, and in North America and Europe, dragonflies are most threatened by pesticides and climate change.

13. Tiny transmitters can monitor dragonflies’ movements.

Scientists have tracked migratory dragonflies by attaching tiny transmitters to their wings with a combination of eyelash adhesive and superglue. In a 2006 study, they found that green darners from New Jersey traveled only every third day and an average of 7.5 miles per day (though one individual traveled close to a shocking 100 miles in a single day). More recently, research revealed green darners complete a multi-generational migration across North America spanning more than 800 miles total.

14. The globe skimmer completes a record-breaking migration.

Despite its modest size of just two inches, a dragonfly called the globe skimmer has the longest migration of any insect—it flies up to 11,000 miles across multiple generations between India and Africa. Aided by winds, the tiny insects will traverse the Indian Ocean with stopovers on islands. Globe skimmers have even been spotted at altitudes of around 20,000 feet in the Himalayas. Their incredible migratory feat has been called the “most extraordinary journey in nature.”

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Filed Under: Animals, Baby Animals, biomimicry, Environment, Eyes, Insects, Migration, Reproduction, Weird Animals, World Records

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