Why don spiders stick to their own webs?
Spiders lay down two types of webbing, says U of T zoology professor Darryl Gwynne: sticky and non-sticky. In fact, some spiders do get stuck in their own sticky webs, mainly by accident. But most are able to bypass the sticky strands and follow the safe trail of non-sticky webs laid down first for their own convenience. Gwynne, who teaches at the University of Toronto at Mississauga, says web-building has several phases. A spider begins by attaching a single strand of silk horizontally between two supports, such as twigs or branches. It then builds an outside rim — almost like a bicycle wheel — and attaches spokes and a spiral from the centre to the outside of the web. These parts of the web are all composed of non sticky silk. With this frame — the foundation for a decent web — firmly in place, the spider adds the sticky strands, once again in a spiral pattern. This spiral is connected to the non-sticky spokes. “So, when a spider runs across from the centre of the web to grab a prey,
