We know that some animals are bilaterian—meaning they display bilateral symmetry—while others are not, but nature is rarely ...

For decades, health experts have relied on body mass index (BMI), a ratio of weight to height, to classify people as underweight, normal weight, overweight or obese. But sometimes, you need more than ...

It might be more than you think.

I grew up in rural Colorado, deep in the mountains, and I can still remember the first time I visited Denver in the early 2000s. The city sits on the plain, skyscrapers rising and buildings extending ...

The original version of this story appeared in Quanta Magazine. It is late at night. You are alone and wandering empty streets in search of your parked car when you hear footsteps creeping up from ...