Here are some possible theories:
1. Non-verbal communication:
* Gestures: Early humans may have used hand gestures, facial expressions, and body postures to convey meaning. This is common in many animal species and is still an important part of human communication today.
* Vocalizations: Simple sounds, like grunts, shouts, and cries, could have been used to express emotions, alert others to danger, or indicate location.
* Mimicry: Mimicking animal sounds or actions could have been a way to convey information or share experiences.
2. Visual communication:
* Cave paintings: While cave paintings are a relatively late development, they suggest that early humans could use visual symbols to represent concepts and stories.
* Tool use: The creation and use of tools, like stone axes or spears, could have been a form of communication, indicating shared knowledge and skills.
* Object manipulation: Arranging objects in specific patterns or creating simple structures could have been used to convey messages.
3. The development of spoken language:
* Proto-language: This is a hypothetical stage where humans developed basic vocal sounds and gestures that began to combine into more complex forms of communication.
* Evolutionary pressures: The need to communicate about food, danger, and social interaction likely drove the development of more complex forms of language.
It's important to note:
* There is no single answer to this question, and we may never know exactly how early humans communicated.
* The development of language was likely a gradual process that involved many different forms of communication.
* We can study animal communication and early human artifacts to gain insights into the possible evolution of human language.
While it's impossible to say for sure what came before spoken language, we can be certain that our ancestors found ways to communicate, share knowledge, and cooperate. This ability to communicate is a fundamental part of what makes us human.