In Chapter Four of this fascinating book that explores the interaction of plants with humans, and how plants use human desires for their own benefit, Pollan turns his attention to the humble potato. Brought back from the Americas in the 16th century, it revolutionised farming, as it was a plant that could grow well and produce bumper harvests in locations that only had poor soil quality and lacked warmth and sunshine. The way in which the Irish quickly became dependent on the potato to feed them is demonstrated in the Irish Potato Famine, which occurred because the Irish only grew one type of potato and therefore when disease struck the Lumper, the type of potato they grew, it had disastrous consquences. Note what Pollan says about the Irish Potato Famine:
The Irish potato famine is the great cautionary tale of putting all your eggs in one basket, and the great cautionary tale about monocultures of all kinds. It's a parable about the importance of biodiversity, and it's a parable we forget at our peril.
In spite of the dangers of monocultures Pollan reports that the largely-American driven desire for straight cut fries has resulted in the rise of another monoculture in the USA, where the Russet Burbank is being farmed in great numbers. The chapter continues by discussing the ability that humans have now to create variability through genetic engineering rather than select for it. Pollan talks about a new genetic enginneered variety of the potato and then discusses genetic engineering vs. organic farming. Throughout this chapter, he shows that we as humans are what we eat through the massive impact our food has on us. It is our desire for straight cut fries that is driving the monoculture of the Russet Burbank, which in turn is driving the calls for genetically engineered versions of the potato. Our diets, or what we eat, says so much about who we are. Those who believe in organic farming are happy to forego their straight cut fries in order to have a range of different potatoes, just as the Irish identity is so much a part of their history, of which the Irish Potato Famine is a hugely tragic part. The relationship betwen our identities and our diet is confirmed.