This week, we will be celebrating the human tongue. Language is one of the key features that makes us human, along with praxis (tool use). In both cases, the evolutionary breakthrough required both cognitive and motor structures. In the case of praxis, we needed both the ability to visualize tools, and the hand to make and use them. Moreover, the hand’s fine sense of touch, along with it’s intricate propioceptive ability, completes the loop. The hand, then, is a key motor and sensory structure in the tool-use domain, and praxis wouldn’t be possible without it.
Likewise, language required an effector organ; and the tongue was it for many thousands of years before the hand got in on the action. Continue reading