Which is the strongest natural fibre known to man?

The spider silk is the toughest natural fibres known in nature. Spider silk is a protein fibre spun by spiders. Spiders use their silk to make webs or other structures, which function as sticky nets to catch other animals, or as nests or cocoons to protect their offspring, or to wrap up prey.

They can also use their silk to suspend themselves, to float through the air, or to glide away from predators. Most spiders vary the thickness and stickiness of their silk for different uses.

In some cases, spiders may even use silk as a source of food, while methods have been developed to collect silk from a spider by force it is difficult to gather silk from many spiders in a small space, in contrast to silkworm "farms".