Writing
The invention of the first writing systems is roughly contemporary with the beginning of the Bronze Age of the late 4th millennium BC. The Sumerian archaic cuneiform script and the Egyptian hieroglyphs are generally considered the earliest writing systems, both emerging out of their ancestral proto-literate symbol systems from 3400 to 3200 BC with earliest coherent texts from about 2600 BC. It is generally agreed that Sumerian writing was an independent invention; however, it is debated whether Egyptian writing was developed completely independently of Sumerian, or was a case of cultural diffusion.
Afroasiatic languages
The earliest written evidence of an Afroasiatic language is an Ancient Egyptian inscription dated to c. 3400 BC (5,400 years ago). Symbols on Gerzean (Naqada II) pottery resembling Egyptian hieroglyphs date back to c. 4000 BC, suggesting an earlier possible dating. This gives us a minimum date for the age of Afroasiatic. However, Ancient Egyptian is highly divergent from Proto-Afroasiatic (Trombetti 1905: 1–2), and considerable time must have elapsed in between them. Estimates of the date at which the Proto-Afroasiatic language was spoken vary widely. They fall within a range between approximately 7,500 BC (9,500 years ago), and approximately 16,000 BC (18,000 years ago). According to Igor M. Diakonoff (1988: 33n), Proto-Afroasiatic was spoken c. 10,000 BC. Christopher Ehret (2002: 35–36) asserts that Proto-Afroasiatic was spoken c. 11,000 BC at the latest, and possibly as early as c. 16,000 BC. These dates are older than those associated with other proto-languages.