What kinds of evidence have been examined to try to determine the time of origin

There have emerged several contradictory theories of human cognitive evolution

in attempts to model how and when these abilities emerged. Various kinds of evidences have been examined in order to estimate the time of origin of human language which includes archaeological evidence, biological or paleoanthropological evidence and even cultural evidence. Ruhlen used a package of archaeological, paleoanthropological and genetic evidence for estimating the date of origin of language diversification. He proposed that this process could have
started 40 to 50,000 years ago. But there also appeared many contradictory theories against his.

Anthropologists have also highlighted tracheal changes as evidence of the origin of human language. Newly uncovered genetic, fossil and archaeological evidences suggest that our ancestors had developed the biological basis for at least a primitive form of speech some half a million years ago. It happened even before the split in human lineage between the Homosapiens and the Neanderthals. Anthropologists have also linked the origin of speech and the uniqueness of the human ability to speak to genetic mutation. (Derrico, n.d.) However, apart from the biological and archaeological evidences, cultural evidences have also been examined to estimate the origins of language and speech. Cultural anthropologists have suggested a cultural model of the origin of language. They have argued that language is a cultural creation which developed
supported by the human biological advantages. Thus, we see that anthropologists have linked a variety of evidences to the development of speech among humans.

While some have cited it as a biological evolutionary phenomenon others have linked it with cultural evolution.