The case against koalas
There was a reason 18th-century rulers were eager for their subjects to grow and eat potatoes: the miraculous tuber offered an alternative source of nutrition to grain, hence reducing bread prices. In the event of a catastrophic harvest, people could survive. To the rulers themselves, however, the biggest benefit was probably what happened when the grain harvest was merely disappointing. With grain no longer critical to survival, the price of bread would be far less volatile. And high bread prices might be more likely to lead to civil unrest than no bread at all. Humans evolved to be foraging omnivores, but agriculture made us over-reliant on whatever crop could best