PENANG, Malaysia - Monkeys in Malaysia have been found to eat rats in such great quantities they could replace chemical pest control on palm oil plantations. Palm oil has been much maligned for its role in driving deforestation, and researchers believe macaques could enhance palm oil sustainability by reducing rat populations. Malaysia produces 30% of the global supply of palm oil, a versatile and cheap vegetable oil used in many foodstuffs as well as consumer products like shampoo. Concerns over the impact of palm oil saw major UK supermarket chain Iceland announce that it would stop using the ingredient in its own brand products in 2018. A November 2016 report from rights group Amnesty International claimed labor abuses were rife on Indonesian palm oil plantations.