This could be evidence of the humble beginnings of twitter :D #AncientHumans via Sciencemag: Torun, Poland - About 100,000 years ago, ancient humans started etching lines and hashtag patterns onto red rocks in a South African cave. Such handiwork has been cited as the first sign our species could make symbols-distinct marks that stand for some meaning-and thus evidence of a sophisticated mind. But a new study, reported here this week at Evolang, a biannual conference on the evolution of language, finds that these markings and others like them lack key characteristics of symbols. Instead, they may have been more for decoration or enjoyment. To come to this conclusion, Kristian Tylén, a cognitive scientist at Aarhus University in Denmark, and his team of cognitive scientists and archaeologists took a closer look at dozens of etched red ochre stones found in the cave, known as Blombos Cave. Some scientists have called the markings early forms of art and even evidence of symbolic behavior