Margaret Thatcher

Thatcher studied chemistry at Oxford under Dorothy Hodgkin and worked as a research chemist for food and plastics firms before retraining as a barrister specialising in tax. She was the first prime minister with a science degree, and in 1989 she gave one of the first major speeches by a world leader on climate change at the UN, drawing on that training. Her legal work in tax law fed her grip of detail. Her science background did not translate into notably higher research spending.