I came across this video of an isolated tribes first ever encounter with a white man. Very intriguing stuff. At roughly the 11min mark they use handshakes. Now it had been my understanding that handshakes came from Europeans and Middle Easterners shaking hands to display that they had no weapon or ill intentions. The narrator gleans that the tribesmen use it for the same exact reason. Did this evolve separately as a gesture or is there a connection between the two identical gestures?
Don't get too excited by the handshake, the video is most likely some acting, these people had been visited before, couple of times. Though the article here didn't mention the handshake.