Ogre-faced spiders can hear without ears

The spider shown in the picture below is called an ogre-faced spider. They are believed to have the largest eyes of any known species of spider, and one of their hallmarks is the ability to see 2,000 times better than humans in the dark. It turns out that incredible eyesight isn’t the only thing these spiders do for them.

New research shows that the ogre-faced spider can hear without ears. The spiders can hear both low-frequency and high-frequency sounds through receptors in their legs. Researchers say they can detect sound from a distance of at least 6.5 feet from the sound source. They are sensitive to frequencies up to 10 kilohertz.

The scientists used both laboratory tests and field observations in their study. They were able to show that hearing stimuli in the same low-frequency range as the wing beats of moths, mosquitoes and flies cause spiders to beat backwards. Backstroke is one of the typical hunting movements of the spider. This led the researchers to discover that the spiders use audible cues to detect and catch flying prey.

Jay Strafstrom, co-author of the study, says the spiders are a “gold mine” of information. The observations made in the study show that the spider not only has incredible visual ability, but can also hear very well. Ogre-faced spiders are tropical in nature and occur worldwide, including the United States, especially Florida.

The spiders are nocturnal and spend the day hiding between fronds of plants. During the day, the creature tends to play dead, and at night to hunt and kill prey. The spiders beat forward to catch prey below them and backward to catch prey that flies overhead, and the study found that hunting methods rely on different senses.