Ogre-faced spiders are skilled predators that jump towards their prey and catch it from the air. They do not have years, but a special organ found on their slim legs allow them to perceive the noise made by small wings.
The aspect of the organ is quite interesting, as it can be seen as a set of slits located near the tip of each leg. Nerve cells are present within the slits and can detect pressure changes in the air, including those caused by moving wings.
With the help of the sensors, ogre-faced spiders can detect sounds over a distance of 2 meters, as well as frequencies ranging between 100 to 10,000 hertz. The frequency range is up to five times higher in comparison to that of humans, as we cannot hear noises above 20,000 hertz.
While humans can detect noises with the help of eardrums, the researchers were fascinated by the fact that ogre-faced excel at capturing their prey despite the fact that they don’t have years, which was the primary reason that led to the elaboration of a new study.
Experiments revealed that select sounds would trigger an instant reaction among the spiders, who would perform the half-backflip move that is used to catch a flying insect. Ogre-faced spiders are quite tiny as they measure less than 1-inch (or 1.5 cm to 2.5 cm). They prefer areas with rich vegetation and can catch moths, flies, and other insects that get too close.
Other tests have shown that the brain of the spiders can react to noises between the range of 1,000 Hz and 10,000 Hz. In this case, they might anticipate the high-pitched noise made by predator birds and avoid them when they are close to their web. Further research will take place as the scientists want to learn if the spider can identify the direction from the sound is coming.
The study was published in a scientific journal.