Open letter to South Africa’s students‚ universities and government‚ represented by Minister in the .
WATER rolls off a duck's back because oil and water don't mix.
When a duck is swimming or out in the rain, it secretes an oil from glands found near its tail. With its bill it then rubs the oil all over its body.
The oil stops water from soaking the duck's feathers, making the bird practically "waterproof". - bigsiteofamazingfacts.com; mdc.mo.gov; machinerylubrication.com