According to a new study from the University of Georgia, the Jorō spider may be the shyest spider ever. "One of the ways people think this spider might affect other species is that it's aggressive and surpasses all other native spiders," said Andy Davis, lead author of the study and a research scientist at UGA's Odum School of Ecology. "So we wanted to understand the personalities of these spiders and see if they have the ability to have this aggression." As it turns out, they didn't. "
While most spiders start moving again shortly after being disturbed, Jorō spiders like this one here remain motionless for more than an hour. Source: Peter Frey/UGA
The researchers compared the responses of more than 450 spiders from 10 different species to short, harmless disturbances.
While most spiders freeze for less than a minute before returning to their normal activities, Jorō spiders remained motionless for more than an hour.
"They're basically shutting down and waiting for the interference to go away," Davis said. Our paper shows that these spiders are indeed more afraid of you, not the other way around. "
In fact, Jorō is relatively harmless to people and pets. Jorōs don't bite unless pressed. Even if you manage to annoy Jorōs in some way and make it bite you, its fangs may not be big enough to pierce your skin.
To study the spider's response to stress, the researchers gently blew two streams of air into the spider with air. This slight disturbance causes the spider to "freeze" for a period of time, absolutely stationary.
The researchers tested more than 30 garden spiders, banded garden spiders and marbled spherical spiders. They also analyzed similar data from previously published, peer-reviewed papers that evaluated the responses of an additional 389 spiders, including five other species.
A female Jorōs spider weaves a web. The 30 mm scale bar is used to refer to the size. Source: Jeremy Howell
All these spiders started moving again after an average of about 1 and a half minutes of rest. However, in most cases, Jorōs remain frozen and do not move their bodies or legs for more than an hour.
The only other spider species that exhibits similar long-term reactions is a cousin of the Jorō spider, known as Trichonephila clavipes, and the Jorō spider come from the same genus.
The East Asian Jorō spider, officially known as Trichonephila clavata, first appeared in Georgia around 2013, and the species is native to Japan, South Korea, Taiwan and Chinese mainland, and likely hitchhiked on a shipping container destined for the continental United States.
Since then, the species has spread rapidly to much of the state and southeastern regions. The number of Jorō spiders can now easily reach the millions. And the Americans have little to do to stop them from expanding.
A Jorō spider is enjoying a caterpillar. Source: University of Georgia
Davis' previous research has even suggested that these invasive arachnids may have spread beyond their current habitat and across much of the eastern seaboard.
"Most people think of 'invasive' and 'aggressive' as synonymous," said Amitesh Anelao, a co-author of the study and an undergraduate researcher at the university. People panic about the Jorō spider at first, but maybe this paper can help calm people down. "
Jorō is often found in areas where native Georgia spiders do not usually inhabit. They build golden nets between wires, on top of traffic lights, and even above the tankers at local gas stations, which are not particularly calm places.
Sunlight shines through the elaborate web of the Jorō spider. Source: University of Georgia
The researchers believe that the shyness of Jorō spiders may help them better tolerate the large amounts of noise, vibration, and visual stimulation they constantly encounter in urban environments. Their prolonged freezing response to being frightened may help conserve the energy of the Jorō spider.
"One thing this paper tells me is that the rapid spread of Jorōs must have been because of their incredible reproductive potential," Davis said. "They're just breeding everyone else. This is not because they are replacing native spiders or kicking them out of their own webs. Arachnophobia sufferers can take comfort from the meekness and gentle temperament of Jorō spiders. However, it is likely that these spiders will stay here. "
"They're very good at getting along with humans," Anero said, "and they probably won't disappear anytime soon." "