Dragonflies, with their shimmering wings and acrobatic flight, are among the most captivating insects. These ancient creatures, predating dinosaurs, showcase remarkable aerial prowess. They do indeed mate while flying, a behavior often described as an “aerial ballet.”
The Aerial Ballet
This feat begins with the male grasping the female behind her head using specialized claspers at the tip of his abdomen. This initial connection forms a “tandem” position, where the male leads the pair through the air. The male’s anal appendages fit into species-specific grooves on the female for a secure hold.
Following the tandem linkage, the female, if receptive, bends her abdomen forward to connect with the male’s secondary genitalia on the underside of his second abdominal segment. This creates a distinctive closed circle or heart-shaped formation, known as the “copulatory wheel” or “heart.” This unique posture allows for the transfer of genetic material while the pair continues to fly, a distinguishing characteristic of dragonflies and damselflies.
The Intricate Mating Process
Dragonfly reproduction involves a unique male reproductive system. Unlike many insects, the male’s sperm-producing primary genitalia are at the tip of his abdomen, on segment nine. However, he possesses secondary genitalia, including a seminal vesicle for sperm storage and a penis, on the underside of his second and third abdominal segments.
Before connecting with the female, the male transfers sperm from his primary genitalia to these secondary structures. This “charging” prepares him for copulation. Once the female connects her genital opening to the male’s secondary genitalia in the copulatory wheel, sperm transfer occurs. Mating duration varies, ranging from a few seconds to several hours, with some males employing specialized structures on their penis to remove sperm from previous mates before transferring their own.
Advantages of Aerial Mating
Aerial mating offers several evolutionary benefits. Mating in flight reduces the pair’s vulnerability to predators compared to being stationary. This constant movement makes them a more challenging target for birds or other insectivores. The ability to mate while airborne also facilitates efficient mate location and pair formation, allowing males to patrol territories and quickly engage with receptive females.
This specialized behavior is a direct adaptation to their predatory, mobile lifestyle. Remaining airborne during reproduction allows them to maintain vigilance and quickly move if disturbed. It also supports the dispersal of their genetic material across suitable aquatic habitats, which are often scattered.
Life After Mating
Following aerial mating, the female lays her eggs, a process known as oviposition. Females often deposit eggs directly into or near water bodies. Common methods include dabbing eggs onto the water surface, inserting them into submerged vegetation, or placing them in mud along the water’s edge.
In many species, the male may remain attached to the female in the tandem position during oviposition, guarding her from other males. This guarding behavior ensures his sperm fertilizes the eggs. After the eggs are laid, they develop into aquatic nymphs, which live underwater for a period before emerging as adult dragonflies.