Feature

Health & Medicine

A gut-brain link for Parkinson’s gets a closer look

Early evidence suggests that Parkinson’s may be a gut disease that affects the brain.

Ecosystems

Beavers are engineering a new Alaskan tundra

Climate change has enabled the recent expansion of beavers into northwestern Alaska, a trend that could have major ecological consequences for the region in the coming decades.

Environment

Engineers are plugging holes in drinking water treatment

Drinking water quality has come a long way in the past hundred years — but challenges remain.

Ecosystems

How mammoths competed with other animals and lost

Mammoths, mastodons and other ancient elephants were wiped out at the end of the last ice age by climate change and spear-wielding humans.