In the early 1970s, for example, the cassava mealybug, a pale, flat, plant-eating insect, was destroying the staple crop of 200 million Africans.

FORBES: Those Resourceful Bugs

There was plenty of sorghum (the local staple crop) in nearby countries and either buying and shipping it by truck or perhaps even just giving money to starving people and watching the market get food to them would be quicker than anything else that could be done.

FORBES: Famine: Don't Send Food, Send Money

The price of pork - a staple of the Chinese diet - has reached a new high, while crop-growing regions have been hit by severe flooding.

BBC: Chinese inflation hits three-year high

Zambia's problems have been compounded by floods which have wiped out a large proportion of this year's crop, coinciding with a shortfall of grain - particularly the country's main staple, maize - across Southern Africa.

BBC: Zambia's economic travails