The weevil species present in PNG are a real concern to almost all gardeners. Why? Because the weevils eat kaukau / kumara / sweet potato, destroying the tuber and delivering a taint that makes them inedible to even hungry pigs.
These weevils are going to push people towards alternative crops – like yam, cassava, potato, banana, corn… but of course most PNG highlanders are still primarily reliant on kaukau for daily starch needs.
See more about the kaukau weevil here. (There’s a set of notes for farmers in the library on this site).