Scientists have for the first time observed tool use in the gorilla. Thomas Breuer and associates witness a gorilla in northern Congo use tree branches for two types of activities. In one instance, the female used a stick to determine the depth of water and then to aid her in crossing the water. The second example was of a gorilla who used a small tree trunk as a stabilizer as she gathered food, and then used the same truck as a small bridge to cross a patch of swamp. It's very interesting to see how our evolutionary relatives use tools for activities that are not food related (as in chimps). It makes you wonder what environmental factors could eventually stimulate in gorillas and chimps for future tool use.