Who invented vocabulary?

The concept of "inventing vocabulary" doesn't have a single originator. Vocabulary naturally evolves from the need for communication among humans. As societies developed, so did language, with the creation of words to represent objects, actions, feelings, and ideas. This process is organic, collaborative, and ongoing, with new words constantly being created and old ones falling out of use. It's not the work of one person, but a complex evolution involving many individuals over thousands of years. The first words were likely simple sounds associated with basic needs and objects, which over time, through the development of various languages and cultures, grew into the complex vocabularies we have today.

Homo erectus, an ancestor of modern humans, is thought to have had some form of communication, potentially including the use of early words. The evidence for this is circumstantial and comes from various sources:

1. Anatomical: Homo erectus had a hyoid bone similar to modern humans, which suggests they could have made a variety of sounds suitable for speech.
2. Technological: The sophistication of Homo erectus tools implies a level of cognitive ability and social learning that may have been supported by some form of language.
3. Social: The apparent social structures and cooperative behavior observed in Homo erectus, such as group hunting and care of the old and sick, suggest that complex communication would have been beneficial, if not necessary.

However, because language doesn't fossilize, and the soft tissues involved in speech decay, we cannot be certain about the complexity of their language or whether it included structured vocabulary as we understand it. The development of words, as we know them, likely took a significant span of time and involved complex social and cognitive changes.