Biology
The Neurobiology of Circadian Rhythms in Nocturnal Primates
Quick fact
Nocturnal primates, like owl monkeys and mouse lemurs, have a circadian clock that is exquisitely tuned to moonlight and twilight, allowing them to time their activity to the dark phase even in dense forests where direct sunlight never reaches the forest floor.
Why this is interesting
You might know that you have an internal body clock that makes you sleepy at night, but what happens when your whole life flips to the dark? Some primates have solved this by rewiring their brains for the night.