Notebook

Ecosystems

Earth’s dry zones support a surprising number of trees

A Google Earth-based estimate of dryland forests adds serious leafage to Earth’s total tree count.

Animals

This glass frog wears its heart for all to see

A newly discovered glass frog species has skin so clear that it reveals most of the animal’s internal organs, including the heart.

Physics

Here’s why your wheelie suitcase wobbles

Physicists explain why roller suitcases rock back and forth as you dash through the terminal.

Health & Medicine

In 1967, researchers saw the light in jaundice treatment

Researchers discovered how to use light to treat babies with jaundice 50 years ago.