Why strange stones are found in a crocodile stomach?

 Crocodile mouth.

Crocodile unusual diet

It has long been known that the crocodile has stones in its stomach, but for some time no one had been able to explain just how they got there or what purpose they serve.

But why does a crocodile swallows stones ?

It seems that crocodiles swallow stones for the very same reason that ballast is taken aboard ship and stored below deck.

The stones, found in the lower part of the stomach, served as a counterweight for the lungs, which are located higher up.

The stones help it keep its balance while in the water.

The average amount of ballast that a crocodile carries is about one percent of its weight.

Almost five kilograms of stones were found in the stomach of a crocodile some fifteen feet long.

Further studies have revealed that young crocodiles having nothing to serve as ballast have difficulty in keeping their balance.