Air moves because the sun heats Earth unevenly. Warmer air rises and cooler air sinks. Air molecules flow from places with lots of air molecules to places with fewer—as wind.

Peng told me that self-driving cars are getting safer. Some studies show that certain driverless cars have fewer crashes than cars driven by people in similar places.

Taking care of butterflies—and other beneficial insects—is one way to make the world a better place. And butterfly lovers in the Pacific Northwest may be in a good position to help our fluttery neighbors.

Wolf biology made them good candidates to live with humans. That includes their social structure and physical needs. Bear biology doesn’t work the same way.

Tastes are chemical signals. They’re picked up by gustatory (taste) receptors in some of the butterfly’s cells.

We see a planet’s color because of the way our eyes and brains process the sun’s light as it reflects off that planet. How it looks depends on the planet’s state and composition.

Mapping shared traits helps scientists build insect family trees. That’s how they figured out that mantises and roaches form a group called Dictyoptera.

Different kinds of birds drink in different ways—from scooping to suctioning, from drinking seawater to getting their water from prey. Birds adapted their drinking techniques to match their environment.

There are about 4,000 species of mosquitoes. They’ve all adapted their strategies to specific host animals. But most mosquitoes bite non-human animals.

Walking upright reshaped the pelvis. Humans adapted by giving birth earlier, when the baby’s head is smaller.