The Unfolding of Language: An Evolutionary Tour of Mankind's Greatest Invention

Tape recorders did not exist in the time of cavemen, making it difficult to know how language started. We can piece together some clues from written texts. However, by the time these texts came into being, language had already been around for some time. We can, however, look at how language has changed.

Often words start out with nouns used to represent a certain thing. Later, these may be adapted to refer to a property of the things. (For instance "orange" refers to both the fruit and the color orange.) Verbs come out of actions related to things. Grammatical constructs arise from different words. These are often simplified as they become more common. ("gonna" is an example today.)

In the past, people would often refer to a rise or decline of language. However, language often changes in more of a loop. Commonly used words may see the sound collapse. Later emphasis may be added bringing back a greater sound. A words may be combined and added, and then later separated. Sounds may change based on patterns of similarity or ease of pronunciation.

This book has an interesting exploration of how language is changing, has changed and may have changed in the past.