Cunning Hunter: Researchers unveil the strategy used by spiders to capture their prey (video).

Horned spiders (Theridiosoma gemmosum) are fascinating because they do not simply passively wait for prey to become ensnared in their webs; they take action. These arachnids prepare a perfectly calculated trap for their target, then catapult themselves to attack — scientists captured this process on camera, as reported by Popular Science.

It is known that horned spiders, also referred to as tangle-web spiders, pull the center of their flat web backward, forming a cone and positioning themselves at its tip. They then hold the web in place by gripping a taut thread, and after releasing it, allow the web to fly. Next, the spider catapults forward when the prey passes by, ensnaring it in their sticky webs.

Back in 2021, biophysicists Saad Bakhmala from Georgia Tech and Todd Blackledge from the University of Akron, along with colleagues, conducted an experiment and discovered something intriguing. The researchers noted that they could make the spiders act with just a snap of their fingers.

In a new study, Blackledge and University of Akron graduate student Sarah Khan focused on proving that spiders can indeed hear approaching insects and wait for their prey to enter the range of their trap. The arachnids then release their web and catapult themselves to consume the catch.

To achieve this, the team spent several hours along local riverbanks, checking crevices and rocks for the characteristic cone-shaped webs with a spider at the end. The main challenge was that horned spiders are very small, making them significantly harder to find. Nevertheless, the team's search was successful.

Next, the team brought the spiders to the lab and set up several branches where they could weave their webs. They also brought the spiders' favorite snacks — mosquitoes and flies. During the experiments, the team attached the insects in such a way that their wings were free, allowing them to make sounds.

The results indicate that the spiders released their webs when mosquitoes were nearby, flapping their wings. However, a closer look at the footage revealed that the insects never touched the web with their protruding front legs. Instead, horned spiders were capable of launching their web even before the mosquito made contact.

The team also utilized a tuning fork tuned to the pitch produced by the flapping wings of a fly. When placed in front of the web, the scientists found that the arachnids still released their sticky trap. The researchers now believe that spiders likely listen for the sounds of approaching insects and release their web as soon as mosquitoes get close enough for the trap to work. It is suggested that spiders use sound-sensitive hairs on their legs to carefully listen for nearby insects.

During the study, the scientists also determined how quickly the webs released by the spiders travel. Khan mapped the trajectory of each spider as they moved along the web while it tore forward. They calculated that the speed of the web can reach an incredible rate — around 1 m/s. The actual attack process, as the study showed, lasts only 38 milliseconds — too quick for the prey to have a chance to escape.

The results also suggest that spiders released their web cones 76% more often when a mosquito was in front of the web. They attempted to release the web when the mosquito was behind them only 29% of the time. It is likely that the sound produced by the insects influences the spiders' behavior.