Neanderthal DNA and the Evolution of Human Language

75% of the world's population carries genetic variations inherited from Neanderthals, which may have resulted in improved brain function.

Approximately 40,000 years ago, hybridization between Neanderthals and modern humans allowed for the transfer of genes that enhanced our cognitive capabilities.

II.3. Evolution and Language

Our ability to generate language is rooted in brain structure. Studies of individuals with brain injuries provide essential information for locating the areas engaged in processing linguistic information.

The cortical areas that control speech are located in the left hemisphere. The two main language processing centers are:

• Broca's area: Responsible for speech coding and production.
• Wernicke's area: Dedicated to speech understanding.

These regions are not unique to our species, nor are they solely involved in the production of vocal sounds or gestures. The emergence of human-specific language likely resulted from a reorganization of primate brain circuitry and the formation of new links with other brain areas.

According to Steven Pinker, the appearance of language may have originated when cortical areas responsible for abstract calculations became linked to areas controlling the flow of information.

The Origins of Proto-Language

It is unknown at what stage of evolution proto-language emerged or the speed at which it evolved. There may be a link between the manufacture of complex tools and language development. William Calvin proposes a theory connecting the cerebral planning required for ballistic movements to the emergence of language. Because ballistic movements require rapid planning—often occurring in one-fifth of a second—corrections are inefficient due to slow reaction times. Calvin's thesis suggests that improvements in the ability to execute these movements resulted in an improvement of our linguistic ability.

II.3.1. Language and Intelligence

Daniel Dennett describes his model for explaining the generation of intelligence as a "tower." In this construction, each level represents a stage of development that improves behavior and adaptation to the environment:

• Gregorian: Use of language.
• Popperian: Ability to develop scenarios and conduct planning.
• Skinnerian: Reinforcing suitable behavioral mechanisms.
• Darwinian: Simple organisms under environmental pressure.

Andy Clark suggests that the incorporation of language involves a fundamental alteration of the brain's circuits and high-level computational structures.