The innovators: the California scientists reinventing the web

The US science startup Bolt Threads can do more than a spider can - it creates and spins stronger, softer, lighter and stretchier silk from scratch

A spider's silk has long been admired by scientists for being incredibly robust - five times stronger than steel - as well as flexible, elastic, soft and stable at high temperatures. They are properties that could be put to use in a wide range of consumer products.

But attempts to produce the silk in large amounts have proved tricky, not least because spiders are cannibalistic and territorial so collecting the material is not economically viable. The thread itself is so fine that it would take millions of spiders to produce a kilogram of silk.