By observing chimps at the Chimfunshi Wildlife Orphanage Trust in Zambia, researchers discovered that chimp communities pass on traditions including secret handshakes from one generation to the next.

These handshakes vary from group to group. Some prefer to clasp hands, while others will clutch wrists.

Mark Bodamer, of Gonzaga University, said: “By following the chimpanzees over time, we were able to show that 20 young chimpanzees gradually developed the handclasp behaviour over the course of the five-year study,” the Daily Telegraph reported.

“These observations support the conclusion that these chimpanzees socially learn their local tradition, and that this might be evidence of social culture,” he added.

If the chimps are indeed masons, they’ve now broken the code of secrecy and will likely face some tough questions from their superiors.

Image: Getty