If spiders aren’t scary enough, tangle-web spiders can catch really, really big prey with their crane-like pulley-system of silk.
Researchers from the University of Trento, Italy, have documented a species of the Theridiidae family – of which the Australian red back is a member – that uses pre-stretched silk to create a pulley system for catching prey 50 times heavier than them.
The team tested the “lifting hunting” technique with different sized beetles, and the spiders were able to capture prey with silk and heave them into their webs with their silky pulleys – an impossibility if they’d been using spidey muscle alone.
This style of hunting allows the spiders to catch prey that’s very large in comparison to themselves, including lizards and small mammals, they report in their paper, published in The Royal Society Publishing.
Interestingly, this means that the spiders are pre-making the strong silk strands for use as an external tool and are also careful to not over-stretch the silk and compromise its elasticity.
Spiderman could learn a thing or two.
Spider capturing prey using web pulleys. Credit: Royal Society Interface.