Interestingly, scientists bred fruit flies for intelligence. They made bananas taste bitter, which fruit flies don’t like. They then gave the flies little markers, so the ‘smart’ ones would avoid the bitter bananas based on this learned signal, the dumb ones would not. After only 20 generations they generated ‘smart’ and ‘dumb’ fruit flies who could learn at different success rates. Then, they mixed them together and saw what happened: Idiocracy, the dumb flies out-reproduced the smart ones! Her take-away was intelligence is costly, and everything has trade-offs.