The Jalaphron were an insectoid species who fed on misery. The Jalaphron left their young on socially unstable planets, where the more turmoil, war and destruction made for a better feast.
Jalaphron were present on Earth for centuries, feeding on the wars that filled humanity's history. The Cold War put an end to the Jalaphron's feast, and they began to starve. The Jalaphron then plotted to start an all-out war by causing the Cuban Missile Crisis. Their plans were stopped by the Fourth Doctor and Edward Grainger. (PROSE: Checkpoint)