The proper science bit – http://www.nature.com/articles/srep22219
Personally I think all this ‘religion’ talk is nonsense. There could be many other reasons for this behavior. I’d go with territory marking since chimps are EXTREMELY territorial and also as a show of dominance. Chimps love a bit of ‘dominance display.’
Actually, apes bloody love war! Go on Koba! Throw some rocks at him!


























































Obviously military training for the coming Ape-ocalypse.