We may take it for grant­ed that the ear­li­est writ­ing sys­tems devel­oped with the Sume­ri­ans around 3400 B.C.E. The archae­o­log­i­cal evi­dence so far sup­ports the the­o­ry. But it may also be pos­si­ble that the ear­li­est writ­ing sys­tems pre­date 5000-year-old cuneiform tablets by sev­er­al thou­sand years. And what's more, it may be pos­si­ble, sug­gests pale­oan­thro­pol­o­gist Genevieve von Pet­zinger, that those pre­his­toric forms of writ­ing, which include the ear­li­est known hash­tag marks, con­sist­ed of sym­bols near­ly as uni­ver­sal as emo­ji.