Photo: Mammals Have "Alarm Detectors" in Noses



Long nerve fibers connect a mouse's olfactory bulb—the green circle seen above—to a ball of microscopic cells called the Grueneberg ganglion at the tip of its nose.

The tiny ganglion, long a mystery to scientists, is actually a sensor used to pick up chemical warning signals sent by fellow animals in distress, according to a study released in August 2008.

Image © Science/AAAS


NEWS FEEDS    After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed. After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed.

Get our news delivered directly to your desktop—free.
How to Use XML or RSS

ADVERTISEMENT

NATIONAL GEOGRAPHIC'S PHOTO OF THE DAY

50 Drives of a Lifetime

Listen to your favorite National Geographic news daily, anytime, anywhere from your mobile phone. No wires or syncing. Download Stitcher free today.