Physicians have used suture to close wounds for at least 4,000 years. Archaeological records from ancient Egypt show that Egyptians used linen and animal sinew to close wounds. In ancient India, physicians used the pincers of beetles or ants to staple wounds shut. They then cut the insects' bodies off, leaving their jaws (staples) in place. Other natural materials used to close wounds include flax, hair, grass, cotton, silk, pig bristles, and animal gut.