Vanuatu has banned them outright, while many Chinese families use just one every 24 hours. So why are Australians still sending millions of dirty nappies to landfill every single day?
New parenthood got our fluid dynamics experts thinking about what ends up in the diaper. They headed to the zoo and the lab to come up with a cohesive physics story for how defecation works.
An increasing number of parents are choosing to toilet train their children from birth, without using nappies. But how effective is this?