Abstract No non-human animal has spontaneously acquired language with open-ended vocabulary and rule-governed syntax. This paper proposes that language was invented by early modern Homo sapiens—a cultural act by cognitively capable individuals. Three clusters of novel hypotheses follow from this invention thesis. First, the language invention cluster: the Evolutionary Barrier to Language Hypothesis posits that no species has evolved language by incremental natural selection alone; the Language Invention Hypothesis proposes that humans invented a Free-Form Protolanguage (FFP) of symbolic words and flexible word combinations without structured syntax—sufficient to convey whole thoughts; and the Two-Stage Language Origin Hypothesis holds that this culturally invented FFP preceded and drove the biological evolution of recursive grammar. Second, the information-theoretic consequences of invention: the Natural Language Codec Hypothesis proposes that vocabulary and grammar function as compression algorithms, producing an effective data rate (EDR) of spoken language far exceeding the acoustic channel rate of ~39 bits/s (Coupé et al., 2019). Third, the biological consequences of invention: the Rapid Language Diffusion Hypothesis posits that language provided decisive competitive advantages, driving global dispersal of H. sapiens; the Language Lifespan Extension Hypothesis proposes that language drove extended human lifespan, generating two subsidiary hypotheses: the Grandparenting Hypothesis, in which knowledge transmission created selection for extended lifespan in both sexes, and the Fossil Menopause Hypothesis, in which menopause is a remnant of the pre-linguistic lifespan limit. Together, these hypotheses suggest that language was the most consequential invention in human history.
G. Immega (Mon,) studied this question.