Evidence and Theories:
* Genetics: Comparing human and chimpanzee genomes suggests language-related genes evolved around 2-3 million years ago.
* Fossil evidence: The shape of the hyoid bone (a small bone in the neck important for speech) in Neanderthals and early Homo sapiens suggests they may have had vocal capabilities.
* Archaeological evidence: Complex tools and symbolic behavior, dating back to the Middle Stone Age (300,000-40,000 years ago), suggest the need for more sophisticated communication.
* Cognitive abilities: Studies on primate communication and language acquisition in humans suggest that the foundations for language might have been in place millions of years ago.
Estimated Time Frames:
Based on this evidence, scientists suggest a range of possibilities:
* Early hominins (7-2 million years ago): Simple forms of vocal communication likely existed.
* Homo habilis (2.4-1.6 million years ago): More complex vocalization and the beginnings of symbolic thought might have emerged.
* Homo erectus (1.8 million - 117,000 years ago): Potentially more sophisticated communication, possibly including basic forms of grammar and syntax.
* Homo sapiens (around 300,000 years ago): The emergence of modern language as we know it, with complex syntax, grammar, and symbolic representation.
It's important to remember:
* Gradual Evolution: Language likely evolved gradually over millions of years, with different stages of development and complexity.
* Multiple Theories: Scientists have various theories about the development of language, and there's no single universally accepted view.
* Ongoing Research: Ongoing research in genetics, archaeology, and cognitive science continues to shed light on the origins of human language.
Ultimately, the exact time and process of language evolution remain an active area of scientific investigation.