Much more than just a net to catch prey, spider webs can transmit lots of information about what has been caught or what might be visiting. Oxford researchers have recently discovered that the strands of silk vibrate at different sound frequencies and in different patterns, giving the spider additional details about what’s going on. It works much like a string instrument. From Wired.co.uk:
The team suspects that spiders may even set out to make a web that ‘sounds right’ so that it can provide the information the spider needs. Evidence that supports this has been observed in the garden cross spider Araneus diadematus which, after finishing building the web, “turns around on the hub and pulls at each radial thread in some sort of sequence; in response to what she ‘feels’ she often readjusts a tension by reconnecting the thread to the hub mesh,” explains Professor Fritz Vollrath, also from the Oxford Silk Group. “This very clearly is a process of tuning” of the overall web tensions, which affects how signal is transmitted.
That may or may not happen a little like this Skunk Bear animation:
via Skunk Bear.