The 300 million year war – Dangerous to delicious (2009)

Sue Hartley

Sue Hartley explores the ways we can manipulate plants to suit our own needs.

Watch time: 48:13
One regular sized courgette and one extremely large courgette
Image credit: Royal Institution

Lecture 4 – Dangerous to delicious

In the fourth lecture from this series, Sue Hartley explores the ways we can manipulate plants to suit our own needs.

In the past, human agriculture has attempted to disarm plant defences and increase their nutrient content. But advances in scientific research have allowed us to move towards cultivating plants that are bigger, healthier, and more edible. The crops on our plates now look, and taste, very different to their wild relatives. 


Over the past 300 million years, plants have had to put up a fight against everything from dinosaurs to hungry caterpillars. But their startling array of defence mechanisms – including poisonous chemicals and cunning ways of communicating with allies – tell us they’re not as helpless as they look.  

In this series of five lectures, Professor Sue Hartley explores the fight between plants and their predators, revealing the tricks plants hold up their sleeves, and how much of our daily lives – from our food to our drugs – is a by-product of this great war.

Sue explains the way plants have evolved to defend themselves, and how herbivores have evolved to overcome this in return. We also see how modern agricultural methods are allowing us to manipulate plants to suit our own needs, and how the changes in our climate may ultimately determine whether it is plants or animals that win the war.

Supporters of the 2009 CHRISTMAS LECTURES