Why do bananas get sweeter as they ripen?

Fruits disperse their seeds when animals eat them. By suddenly increasing the sugar content, plants encourage animals to selectively eat the fruits with mature seeds that have developed the protective coatings they will need to survive passage through the digestive system.

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Why we still don’t understand sleep, and why it matters

For the first 20 years of his life, Henry Nicholls had a healthy relationship with sleep. Shortly after his 21st birthday, he began to experience symptoms of narcolepsy, a debilitating disorder that’s plagued him ever since. Sleep research is progressing, so why are he and others like him still waiting for a cure?

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