So...we know that homo (not always) "sapiens" not only invent new skills, but are able to pass them along by teaching these skills to others. Non-human primates have demonstrated this ability in captivity, but does this kind of "cultural" dissemination happen in a state of nature? Do our closest biological relatives, chimpanzees and gorillas, capable of creating new knowledge and passing it on through quasi-human "cultural" paths?

Not nearly as often as we thought, according to researchers in the African nation of Cameroon. Tool-using skills, such as using a stone to crack open nuts, are a rare innovation among wild chimps. If such a skill spreads at all, it's generally confined to chimps of the same immediate family and direct descendants.

In Cote d'Ivoire in west Africa, chimps living in the forests west of the the N’Zo-Sassandra River were able to use stones as nutcrackers. These chimps were unable to cross the river, so it was believed that this geographic barrier would prevent the nut-cracking skill from spreading further.

Now, two primatologists from the Conservation for Endangered Species, Bethan Morgan and Ekwoge Abwe,  have observed chimps doing the same thing over a thousand miles away.  Since there has been no contact between the two groups of chimps, how did the latter acquire this skill? Morgan says that the skill may have spread beyond the river, then died out - but this is unlikely. "As far as I’m aware, there’s no precedent for a cultural trait in chimpanzees becoming extinct," she says. It is more probable that the skill was developed independently by different individuals.

In any event,  this raises serious questions on how chimps learn new skills and - by extension - how our own more recent ancestors developed and passed on their own skills.