Crocodiles Really Shed Tears While Eating, Study Says

<< Back to Page 1   Page 2 of 2

(See photos of alligators and crocodiles.)

The animals were fed a diet of dry, dog-treat-like biscuits, and they shed tears during most meals.

Some of the reptiles even produced more dramatic foaming around their eyes.

"At times you can see big bubbles coming up in the corner of the eye, sort of like soap bubbles," Vliet said.

In crocodiles, Vliet believes the weeping may be a byproduct of another feeding behavior: the hisses and huffs that crocs make while dining.

These acts may force air though the reptiles' sinuses, where they stimulate fluid in the tear, or lacrimal, glands and force them into the eyes—sometimes to the point of overflow.

Even simpler explanations could also account for crocodiles' tears.

"The general contraction of jaw muscles during the bite reflex may help to squeeze tears out of the lacrimal glands [and] ducts," croc expert Britton said.

"[Another] explanation is that accumulated tears that well up below the eye are simply displaced and run down the jaws when the crocodile moves its head to eat, and it's easy to associate that 'crying' with eating."

In the violent world of crocodiles, tears likely play a protective role.

"There's a lot of drama going on around the head while they are subduing prey," Vliet said. He noted that a croc's eyes also recede into its head as the animal manipulates its mouth.

"They may just be trying to protect the eye."

Free Email News Updates
Sign up for our Inside National Geographic newsletter. Every two weeks we'll send you our top stories and pictures (see sample).

<< Back to Page 1   Page 2 of 2


SOURCES AND RELATED WEB SITES

ADVERTISEMENT

NATIONAL GEOGRAPHIC'S PHOTO OF THE DAY

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

National Geographic Daily News To-Go

Listen to your favorite National Geographic news daily, anytime, anywhere from your mobile phone. No wires or syncing. Download Stitcher free today.
Click here to get 12 months of National Geographic Magazine for $15.