Why the Animals (Gorillas) eat decayed Wood and Lick Tree Stumps

After observing mountain gorillas in Uganda for nearly a year, it’s been believed why the animals eat decayed wood and lick tree stumps, behaviors that have puzzled primate researchers for decades.

The answer for the sodium.

Gorillas in the Bwindi Impenetrable National Park in Uganda will suck on wood chips for several minutes before spitting them. Sometimes they chew on them until their gums bleed. They have also been seen licking the bases of tree stumps and the insides of decayed logs, and breaking off pieces of wood to munch on later. Gorillas will return daily to the same stump and take turns feeding.

Baffled researchers figured maybe the wood was providing some kind of medicinal benefit, by reducing parasites and gastric upsets.The researchers analyzed these items for their sodium content and found that the decayed wood was the source of over 95% of the animal’s dietary sodium, even though it represented only about 4% of their wet weight food intake. Many animals have a specific appetite for sodium and will actively seek it out if their bodies lack the nutrient,

Up to now its not figured out how the wood eating behavior developed. It’s possible that the gorillas learned through trial and error to select foods containing needed nutrients.