Recent research sug­gests that domes­tic dogs seem capa­ble of dis­play­ing a rudi­men­tary “the­ory of mind” — a very human char­ac­ter­is­tic whereby you are able to attribute men­tal states to oth­ers that do not nec­es­sar­ily coin­cide with your own (in a nut­shell). Stray domes­tic dogs, mean­while, do not dis­play this trait, sug­gest­ing that such men­tal attrib­utes are devel­oped through close con­tact with humans. That’s inter­est­ing, but not the main rea­son I’m shar­ing this infor­ma­tion with you.

This cog­ni­tive dif­fer­ence between stray domes­tic dogs and their house­bound brethren was uncov­ered by test­ing whether or not they under­stood the very human action of point­ing (y’know, with your index fin­ger). What struck me most in this dis­cus­sion was this brief the­ory of how the action of point­ing evolved:

Go ahead, let your wrist go limp and look at your hand from the side, or if you’re too inse­cure in your own sex­u­al­ity, just pic­ture Adam’s limp wrist at the moment of cre­ation in Michelangelo’s mas­ter­piece on the Sis­tine Chapel’s ceil­ing. See how even in this relaxed state the index fin­ger is slightly extended? By con­trast, when chimps do this […] their index fin­ger falls nat­u­rally in line with their other fin­gers. Povinelli and Davis rea­son that this sub­tle evo­lu­tion­ary change in the mor­phol­ogy of our hands, which occurred after humans and chim­panzees last shared a com­mon ances­tor five mil­lion to seven mil­lion years ago, is at least par­tially respon­si­ble for the fact that human point­ing with the index fin­ger is so cul­tur­ally ubiq­ui­tous today.

The argu­ment goes some­thing like this. When young infants begin reach­ing for objects just out of their range, adults are most likely to respond to those reach­ing attempts and to retrieve the item for the baby when the latter’s index fin­ger is more promi­nently extended. That is to say, ini­tially, the adult mis­tak­enly reads into the child’s reach­ing attempt as a com­mu­nica­tive ges­ture on the part of the child. Over time, this dynamic between the child and adult serves to fur­ther “pull out” the index fin­ger because the child implic­itly learns the behav­ioral asso­ci­a­tion, so that it slowly becomes a gen­uine point­ing gesture.