According to the findings, the split seems to have been caused when a senior male called Leakey died in 1970. After which, there was a power struggle between a pair of brother chimps from the south and a chimp from the north. When no victor could be found, the groups retreated with their leaders, and subsequently the northern group killed the males from the southern one. The research is being celebrated as a way that we can learn how human social groups fracture over time -- so hopefully the next time there's some drama on Facebook, you'll just need to click a button and you'll instantly unfriend whoever the algorithms believe you'll want to dump.