Almost 80,000 years before humans began using chemical sprays to control insect pests, Africans were using mattresses made from bug-repelling plants to ensure a good night's sleep.

The finding, published in the journal Science on Friday, derives from 77,000-year-old plant bedding found in a cave in South Africa's KwaZulu Natal province. The find is 50,000 years older than any previous prehistoric beds discovered.

The bed's insect-repelling capabilities suggest ancient humans were well aware of the chemical and medicinal properties of some plants.

"The leaves contained chemicals that repelled mosquitoes and other insects, so we know that they understood medicinal plants," says Lyn Wadley, an archaeology professor at the University of the Witwatersrand.

China Daily - Reuters