A biologia e a evolução da fala: por que só os seres humanos falam?

quinta-feira, março 14, 2019

The Biology and Evolution of Speech: A Comparative Analysis
Annual Review of Linguistics

Vol. 4:255-279 (Volume publication date January 2018) 


W. Tecumseh Fitch

Department of Cognitive Biology, University of Vienna, Vienna 1090, Austria

Copyright © 2018 by W. Tecumseh Fitch. This work is licensed under a Creative Commons Attribution-ShareAlike 4.0 (CC-BY) International License, which permits unrestricted use, distribution, and reproduction in any medium and any derivative work is made available under the same, similar, or a compatible license. See credit lines of images or other third-party material in this article for license information.


Abstract

I analyze the biological underpinnings of human speech from a comparative perspective. By first identifying mechanisms that are evolutionarily derived relative to other primates, we obtain members of the faculty of language, derived components (FLD). Understanding when and why these evolved is central to understanding the evolution of speech. There is little evidence for human-specific mechanisms in auditory perception, and the hypothesis that speech perception is “special” is poorly supported by comparative data. Regarding speech production, human peripheral vocal anatomy includes several derived characteristics (permanently descended larynx, loss of air sacs), but their importance has been overestimated. In contrast, the central neural mechanisms underlying speech production involve crucial derived characteristics (direct monosynaptic connections from motor cortex to laryngeal motor neurons, derived intracortical dorsal circuitry between auditory and motor regions). Paleo-DNA from fossil hominins provides an exciting new opportunity to determine when these derived speech production mechanisms arose during evolution.

Keywords human evolution, speech perception, speech production, evolution of language, monosynaptic connections, paleo-DNA