The Fascinating Life Cycle of a Silk Worm

The silkworm is the larva stage of the silk moth's life cycle. Moths lay eggs which develop into the silkworm larvae. They eat for 20-30 days, consuming large amounts of mulberry leaves, and molt through four changes of skin. The silkworm spins a cocoon for protection, to permit the development of the pupa or chrysalis, which takes about three days to be fully completed, and is a similar size to a peanut shell.

The chrysalis emerges from the cocoon as a moth. In cultivated, commercially viable, silk the grub is terminated while still inside the cocoon so that the long filaments are maintained and preserved for the production of silk.
The colour of the silk filament can be determined by the diet of the larvae and seasonal influences. Mulberry leaves produce the preferred lighter coloured cocoons, but in the wild silk worms will eat other plants as well producing a variety of colours.