If Dragonflies Were Bigger, They'd Rule the Food Chain

Who or what do you think is the most effective hunter on Earth? Surprisingly, it's not lions, sharks, eagles, or wolves. Sharp teeth, a loud roar, huge claws, and a terrifying appearance do not automatically make an animal a good hunter. The primary indicator of a beast's effectiveness lies in its ability to successfully catch prey. Lions, for instance, manage to catch their dinner in only one out of four attempts, while sharks succeed in their attacks only half of the time. Wolves and eagles have to exert considerable effort to secure their meals. However, there is one creature that consistently achieves success in its hunts: the dragonfly.

More than 90% of a dragonfly's attempts to catch prey are successful. If dragonflies were the size of giant griffins, they would undoubtedly dominate the top of our planet's food chain. In the distant past, these insects were even larger in the Carboniferous period, but we'll delve into that later. For now, let's explore what makes dragonflies so effective.

One of the main factors contributing to their successful hunting is their speed and maneuverability. Dragonflies possess some of the most efficient wings in the world, allowing them to hover in the air, change direction within seconds, come to a stop, fly backward, and even maneuver in circles. In contrast, birds, which may be graceful in flight, lack maneuverability. They take approximately a second or more to take off, and their movements are smooth and limited. Dragonflies, with four wings that can move independently of one another, can reach speeds of 30 mph with just three wing strokes.

Additionally, dragonflies have a short braking distance, allowing them to come to an abrupt stop at any moment. This remarkable ability, coupled with their rapid and elusive movements, renders them hunters from which nothing can escape. Despite these advantages, effective wings alone are insufficient without a well-functioning brain.

Dragonflies primarily rely on their exceptional eyesight, allowing them to focus on a target just like humans. Their eyes occupy most of their head, consisting of thousands of small lenses, enabling them to see almost 360° around them. Some species even possess ultraviolet vision, providing clear perception of their surroundings and allowing them to maintain focus on a target during flights.

Their brains, located in their chest, are connected to their thorax, forming a chain of 16 neurons that transmit signals rapidly during flight. This communication guides their wings, ensuring they can capture their intended target with precision. Dragonflies prey on mosquitoes, moths, butterflies, flies, and even other dragonflies, using their strong and prickly legs to grip their prey tightly.

However, despite their effectiveness, dragonflies are not the primary predators in the wild. They can become prey for toads, birds, fish, and even turtles, as they often fly over swamps, ponds, and lakes. Nevertheless, if dragonflies were as big as they were 300 million years ago, before dinosaurs roamed the Earth, they would have fewer enemies.

In the prehistoric era, bugs with a wingspan of about 2 and 1/2 feet soared through the air, known as Griffin flies. These creatures resembled dragonflies the size of crows. However, their substantial weight made them clumsy, prompting evolution to reduce their size for increased maneuverability. The decrease in size coincided with the appearance of large prehistoric birds, making giant dragonflies easy prey in the sky.

Now, let's shift our focus to another insect with exceptional flying abilities: the common house fly. Despite being a nuisance, a house fly's attention and reaction speed are several times better than humans. Their ability to change speed and direction, calculate trajectories, and perceive threats make them formidable opponents.

In conclusion, the dragonfly stands out as Earth's most effective hunter, showcasing unparalleled speed, maneuverability, and visual acuity. Its success in hunting, combined with its evolutionary adaptations, places it at the top of the food chain in its ecological niche. So, next time you see a dragonfly darting through the air, appreciate the intricate combination of biological traits that makes it an extraordinary predator.