City Spiders Build Soundproof Webs To Filter Out Urban Noise

North American funnel-weaving spiders can change how their webs transmit vibrations depending on whether they live in noisy cities or quiet rural areas. According to a study published in Current Biology, city spiders build webs that filter out loud background noise. Rural spiders, meanwhile, build webs that amplify the specific vibrations they need to catch food.

The Study

Researchers Brandi Pessman and Eileen Hebets from the University of Nebraska-Lincoln studied Agelenopsis pennsylvanica spiders. Because spiders lack ears, they rely entirely on real-time vibrations in their webs to sense prey. Pessman explained that webs act as extensions of the spider sensory system rather than simple bug nets. The research team collected spiders from both city and country locations, placed them in lab arenas, and exposed them to white noise for four days. Testing 60 webs with controlled vibrations revealed that city spiders dampened a broad range of frequencies at short range. In contrast, rural spiders built webs that retained energy across a narrow frequency range at long range.

Expert Reactions

Urban ecology researcher Shannon Olsson noted that chronic exposure to urban environments clearly changes how spiders build their homes and respond to signals. However, Olsson pointed out that further tests are still needed to confirm if these web changes are true evolutionary adaptations and if they affect prey capture success. Olsson also highlighted that noise pollution has immediate impacts on wildlife that often get overlooked due to a global focus on carbon pollution. Vrinda Ravi Kumar, an evolutionary biologist based in the Czech Republic, is also noted in the reporting.

Context

Animals in rapidly growing cities face constant environmental pressures like loud noise and habitat loss that alter their natural behaviours. Understanding these impacts helps researchers protect urban wildlife and manage ecosystems more effectively.